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The blue book: Guidelines for the control of infectious diseases i

The blue book

Guidelines for the control of infectious diseases ii The blue book: Guidelines for the control of infectious diseases

Acknowledgements Disclaimer

These guidelines have been developed These guidelines have been prepared by the Communicable Diseases Section, following consultation with experts in the Public Health Group. The Blue Book – field of infectious diseases and are based Guidelines for the control of infectious on information available at the time of diseases first edition (1996) was used as their preparation. the basis for this update. Practitioners should have regard to any We would like to acknowledge and thank information on these matters which may those who contributed to the become available subsequent to the development of the original guidelines preparation of these guidelines. including various past and present staff Neither the Department of Human of the Communicable Diseases Section. Services, Victoria, nor any person We would also like to acknowledge and associated with the preparation of these thank the following contributors for their guidelines accept any contractual, assistance: tortious or other liability whatsoever in A/Prof Heath Kelly, Victorian Infectious respect of their contents or any Diseases Reference Laboratory consequences arising from their use. Dr Noel Bennett, content editor While all advice and recommendations are made in good faith, neither the Dr Sally Murray, content editor Department of Human Services, Victoria, Ms Kerry Ann O’Grady, content editor nor any other person associated with the preparation of these guidelines accepts legal liability or responsibility for such advice or recommendations. Published by the Communicable Diseases Section Victorian Government Department of Human Services Melbourne Victoria

May 2005

© Copyright State of Victoria, Department of Human Services 2005

This publication is copyright. No part may be reproduced by any process except in accordance with the provisions of the Copyright Act 1968.

Authorised by the State Government of Victoria, 555 Collins St, Melbourne.

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This document may also be downloaded from the Department of Human Services web site at: www.health.vic.gov.au/ideas/bluebook The blue book: Guidelines for the control of infectious diseases iii

Contents

Acknowledgements ii Hepatitis C 79 Ringworm or tinea 181 Disclaimer ii Hepatitis D (delta hepatitis) 83 Ringworm (tinea) information sheet 183 Introduction 1 Hepatitis E 85 Ross River disease 185 Notification of infectious diseases 2 87 Rotaviral gastroenteritis 187 Abbreviations used 4 Human immunodeficiency Rubella (German ) 189 Acute bacterial conjunctivitis 6 virus or acquired 191 Amoebiasis 7 immunodeficiency syndrome 89 193 Anthrax 8 Hydatid disease (echinococcosis) 93 Scabies information sheet 195 Ascariasis (round worm ) 13 (school sores) 95 Guide to scabies management Barmah Forest virus disease 15 Impetigo (school sores) in residential care facilities 197 Botulism 17 information sheet 97 Severe acute respiratory (undulant , Infectious mononucleosis syndrome (SARS) 199 Malta fever) 19 (glandular fever) 99 207 Campylobacter infection 21 Influenza 101 Smallpox (variola) 209 or Invasive pneumococcal disease 105 Staphylococcal infections 215 (varicella /herpes zoster) 23 Japanese encephalitis 107 Streptococcal disease (genital infection) 27 Kunjin virus disease 109 (Group A beta-haemolytic Chlamydophila pneumoniae 29 Legionellosis (Legionnaires’ ) 217 31 disease) 111 219 Creutzfeldt-Jakob disease (CJD) 33 (Hansen’s disease) 115 Taeniasis 223 Croup or bronchiolitis 37 117 Tetanus 225 Cryptococcal infection 119 227 (cryptococcosis) 39 Malaria 123 Typhoid and 229 Cryptosporidiosis 41 Measles (rubeola) 127 Verotoxin producing E. coli infection 43 131 (VTEC) 231 Dengue virus disease 45 133 Viral gastroenteritis Diphtheria 47 137 (not rotavirus) 233 Donovanosis 51 Molluscum contagiosum Viral haemorrhagic 235 infectiosum (human information sheet 138 239 parvovirus infection or Mumps 139 Appendix 1: Contacts 243 slapped cheek disease) 53 Murray Valley encephalitis virus 141 Appendix 2: Glossary 245 Slapped cheek infection Mycobacterial infections Appendix 3: Standard and information sheet for (non-) 145 additional precautions 247 pregnant women 55 Mycobacterial infections Appendix 4: Procedure for Slapped cheek infection (tuberculosis) 147 managing an exposure to information sheet 56 Mycobacterium ulcerans 151 blood/body fluids/ Food or water-borne illness 57 Pediculosis or head lice 153 substances 253 Common food or water-borne Pertussis () 155 Appendix 5: Procedure for pathogens 60 Pinworm infection (threadworm) 157 managing spills of blood Giardiasis 63 161 and body fluids/substances 257 Gonorrhoea 65 Poliomyelitis 163 Appendix 6: Cleaning and influenzae Psittacosis (ornithosis) 167 waste disposal procedures 259 infections 67 Psittacosis information sheet 169 Appendix 7: Infections in Hand, foot and mouth disease 69 171 children’s services centres 263 Hand, foot and mouth disease Rabies and Australian bat Appendix 8: School exclusion information sheet 70 lyssavirus 174 table 265 Hendra and Nipah 71 Rabies and Australian bat lyssavirus Hepatitis A 73 exposure information sheet 176 75 Rickettsial infections 179 iv The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 1

Introduction

The blue book: guidelines for the control The first edition of The blue book: • Health Translations Directory, links to of infectious diseases has been published guidelines for the control of infectious health information that has been by the Communicable Diseases Section, diseases (1996) was used as the basis translated into various different languages, Public Health Group, Victorian for this second edition. As treatments www.healthtranslations.vic.gov.au Department of Human Services, to assist change over time health care workers • Victorian Department of Human public health practitioners in the should consult the current version of Services 1998, Guidelines for the prevention and control of infectious Therapeutic guidelines: investigation of gastrointestinal illness, diseases. (Therapeutic Guidelines Limited) for up to http://www.health.vic.gov.au/ideas/ The Department of Human Services is date information. The blue book is not intended to replace appropriate referral Other sources committed to enhancing and protecting • Australian Government Department of the health and well-being of all or the need to seek further professional advice. Health and Ageing 2004, Infection Victorians. Our challenge, together with control guidelines for the prevention of public health practitioners, is to reduce References of infectious diseases in community risk from communicable The following sources were used in the the health care setting, disease in Victoria through the preparation of the guidelines: http://www.icg.health.gov.au/ implementation of patient focused and population focused control strategies • Therapeutic Guidelines Limited 2003, • Centers for Disease Control and based on surveillance and risk Therapeutic guidelines – antibiotic, Prevention, Atlanta USA, www.cdc.gov assessment. version 12. • Food Standards Australia New Zealand, Information for each disease in this • Heymann D, 2004 Control of http://www.foodstandards.gov.au/ edition covers: communicable diseases manual, 18th • National Health and Medical Research edn, American Public Health • Victorian statutory requirement for Council 2003, The Australian Association (the 17th edition, Chin J notification and exclusion immunisation handbook, 8th edn, ed. 2000, was used in compiling The www.immunise.health.gov.au • infectious agent(s) blue book). • National Health and Medical Research • identification Further information Council 2001, Staying healthy in child • Together with the references above, the care, 3rd edn, Australian Government • public health significance and following resources provide further Department of Health and Aged Care, occurrence information. http://www.health.gov.au/nhmrc/ • reservoir Victorian Department of Human Services • mode of transmission Fact sheets, surveillance reports, • period of communicability Departmental policies and guidelines, • susceptibility and resistance and online ordering of resources can be • control measures for patients and accessed at contacts http://www.health.vic.gov.au/ideas/ • outbreak measures • Better Health Channel, information for the public, www.betterhealth.vic.gov.au • international measures if applicable • Clinicians Health Channel, • sources of further information if www.health.vic.gov.au/clinicians applicable 2 The blue book: Guidelines for the control of infectious diseases

Notification of infectious diseases

Notifiable infectious diseases are Group A diseases Group B diseases included in Schedule 3 of the Health Group A diseases require notification to Group B diseases require written (Infectious Diseases) Regulations 2001 the Department of Human Services by notification only within five days of and are divided into four groups on the telephone or fax upon initial diagnosis diagnosis. basis of the method of notification and (presumptive or confirmed) with written • Arbovirus infections the information required. notification to follow within five days. • Ross River virus Notification forms are available from the • Anthrax Department: • Barmah Forest virus • Arbovirus infections Telephone 1300 651 160 • Dengue virus – Japanese encephalitis virus Or print or order online at • Kunjin virus – Murray Valley encephalitis virus www.health.vic.gov.au/ideas • other Arbovirus infections • Botulism All notifications and related inquiries • Brucellosis • Cholera should be directed to: • Campylobacter infection • Diphtheria Communicable Diseases Section • Creutzfeldt-Jakob disease (CJD) Public Health Group • Food-borne and water-borne illness Department of Human Services (two or more related cases). • Cryptosporidiosis Reply Paid 65937 • Haemolytic uraemic syndrome (HUS) • Giardiasis Melbourne VIC 8060 • Legionellosis • Hepatitis A Telephone 1300 651 160 • Hepatitis B Facsimile 1300 651 170 • Measles • Hepatitis C For urgent notifications after hours: • Hemophilus influenzae, type B infection (meningitis, epiglottitis, other • Hepatitis D Contact the Duty Medical Officer invasive infections) • Hepatitis E via pager service 13 22 22 and quote pager number 46870 • Meningococcal infection (meningitis or • Hepatitis viral (not further specified) meningococcaemia) • Influenza (laboratory confirmed) • Plague • Leprosy • Poliomyelitis • Leptospirosis • Rabies • Listeriosis • Severe acute respiratory syndrome • Lyssavirus – Australian bat lyssavirus (SARS) • Lyssavirus – other (specify) • Smallpox • Malaria • Tularaemia • Mumps • Typhoid and paratyphoid fevers • Mycobacterium ulcerans • Viral haemorrhagic fevers • Pneumococcal infection (invasive) • Yellow fever • Psittacosis (ornithosis) • Pertussis •Q Fever The blue book: Guidelines for the control of infectious diseases 3

• Rubella (including congenital rubella) • Acquired immunodeficiency syndrome Immediate notification must be made by • Salmonellosis (AIDS) telephone followed by notice in writing within 5 days specifying the micro- • Shigellosis • Human immunodeficiency virus (HIV) infection organism isolated or detected, date of • Tetanus isolation or detection, source (food or • Tuberculosis Laboratory notification water) and any batch identification (if Around Australia and overseas it has appropriate). • variant Creutzfeldt-Jakob disease been recognised that laboratory (vCJD) notification of infectious diseases should • Verotoxin-producing be an integral part of any disease (VTEC) surveillance system. Group C diseases The Health (Infectious Diseases) Group C diseases include the sexually Regulations 2001 require laboratories to transmissible diseases and should be notify tests indicating the probable notified using the same form. To preclude presence of a human pathogenic identification of the patient, only the first organism associated with an infectious two letters of the given and family name disease listed above. The notification of the patient are required. should state the laboratory finding, the family name and given name of the • Chlamydia trachomatis genital patient (except for Group C diseases), infection the age, sex and postcode of the patient, • Donovanosis and the name, address and telephone • Gonococcal infection number of the doctor requesting the test. • Syphilis/ In addition to the above, the Health (Infectious Diseases) Regulations 2001 Group D diseases require notification from laboratories of Group D diseases include HIV infection the following micro-organisms isolated or (human immunodeficiency virus) and detected in food or water supplies: AIDS (acquired immunodeficiency • Campylobacter spp syndrome) and written notification is required within five days of confirmation • Cryptosporidium spp of diagnosis. A separate form is used for • Salmonella spp this purpose due to the need to have • Verotoxin producing Escherichia coli national uniformity in collection of data. (VTEC) Copies of this form are available from the Communicable Diseases Section, • Vibrio spp telephone 1300 651 160. • Giardia cysts • Listeria monocytogenes • Cyclospora spp 4 The blue book: Guidelines for the control of infectious diseases

Abbreviations used

ADT adult diphtheria tetanus HIV human immunodeficiency vaccine virus ALT alanine aminotransferase IG immune globulin anti-HBc hepatitis B core antibody IHA indirect haemagglutination anti HBs hepatitis B surface antibody IM intramuscular CF/CFT complement fixation test IV intravenous CNS central nervous system MDU Microbiological Diagnostic CSF cerebro-spinal fluid Unit CT Scan computerised MIF micro immunofluorescent tomography test DTP diphtheria tetanus pertussis MMR measles-mumps-rubella vaccine vaccine DTPa diphtheria tetanus acellular MRI magnetic resonance pertussis vaccine imaging dTpa adult/adolescent NHMRC National Health and Medical formulation diphtheria Research Council tetanus acellular pertussis PCR polymerase chain reaction vaccine VIDRL Victorian Infectious EBV Epstein-Barr virus Diseases Reference EEG electroencephalogram Laboratory EIA enzyme immunoassay WHO World Health Organization ELISA enzyme-linked immunosorbent assay EM electron microscopy FA direct fluorescent or immunofluorescent antibody test HAV hepatitis A virus HBIG hepatitis B immune globulin HbsAg hepatitis B surface antigen HbeAg hepatitis B e antigen HBV hepatitis B virus HCV hepatitis C virus HDV hepatitis D virus Hib type b The blue book: Guidelines for the control of infectious diseases 5

Acute bacterial conjunctivitis

Victorian statutory requirement Method of diagnosis Period of communicability Infections with Mild conjunctivitis is rarely investigated It is infectious while there is discharge. (Group A disease) must be notified and is usually treated empirically. immediately by telephone or fax followed Microscopic examination of a stained Susceptibility and resistance by written notification within five days. smear or culture of the discharge is Everyone is susceptible to infection and required to differentiate bacterial from repeated attacks due to the same or Infections with Chlamydia trachomatis viral or allergic conjunctivitis. different bacteria are possible. Maternal (Group C disease) must be notified in infection does not confer immunity to the writing within five days of diagnosis. Incubation period child. Infections with The incubation period is usually 24–72 (Group C disease) must be notified in hours. In the case of trachoma Control measures writing within five days of diagnosis. incubation is 5–12 days. Preventive measures Preventative measures include careful Other pathogens are not notifiable. Public health significance treatment of affected eyes and personal School exclusion: exclude until discharge and occurrence hygiene, particularly hand washing. from the eyes has ceased. Acute bacterial conjunctivitis is Control of case widespread throughout the world. Conjunctivitis due to bacterial infection Infectious agent Outbreaks of gonococcal conjunctivitis Haemophilus influenzae and may be difficult to distinguish clinically have occurred in northern and central Streptococcus pneumoniae are the most from allergic or viral conjunctivitis or that Australia. Infection due to Chlamydia common causes but Staphylococcus due to physical irritation. Therefore, trachomatis (trachoma) continues to be a aureus, , empirical antibiotic therapy is often used. significant public health concern in Neisseria gonorrhoeae, Neisseria Patients with significant eye pain, loss of Aboriginal communities and is a major meningitidis and Chlamydia trachomatis vision or photophobia require immediate cause of preventable blindness (trachoma serovars A-C) can referral to an ophthalmologist. worldwide. occasionally be implicated. In mild cases propamidine eye drops are The of acute bacterial the usual treatment. Identification conjunctivitis in Australia due to causes Clinical features other than trachoma and gonococcal In moderate and severe cases a The clinical syndrome ranges from mild infection is not well documented. combination of treatments may be used. redness of the conjunctivae to corneal Infections are most common in children Consult the current version of infiltration and visual disturbances in under five years of age and Therapeutic guidelines: antibiotic neglected cases. A purulent exudate is decreases with age. (Therapeutic Guidelines Limited). An eye almost always present. Trachoma should ointment may be used at bedtime. Soiled be suspected in the presence of Reservoir articles should be discarded or lymphoid follicles and diffuse Humans. disinfected. Rigorous hand washing before and after eye examinations and conjunctival inflammation or trichiasis Mode of transmission (inturned eyelashes). Specialist toilets is important in preventing further Infection is transmitted via contact with ophthalmological advice should be transmission. Children should not attend the discharge from the conjunctivae or sought in this case. school and child care settings until upper respiratory tract of infected discharge from the eyes has ceased. persons. Neonates may acquire infection during vaginal delivery. In some areas flies have been suggested as possible vectors. 6 The blue book: Guidelines for the control of infectious diseases

Control of contacts With the exception of gonococcal or meningococcal conjunctivitis, contact tracing is not applicable in most situations in Victoria. Refer to the relevant sections for the management of persons in contact with these infections. Control of environment Dispose of contaminated articles carefully.

Outbreak measures Public health action in an outbreak is dependent on the type of infection and the setting in which it has occurred. The blue book: Guidelines for the control of infectious diseases 7

Amoebiasis

Victorian statutory requirement Method of diagnosis Public health significance Notification is not required. Diagnosis is confirmed by microscopic and occurrence examination for trophozoites or cysts in: School exclusion: exclude until diarrhoea Occurrence is worldwide. has ceased. • fresh or suitably preserved faecal rates tend to be higher in: specimens • areas with poor sanitation Infectious agent • smears of aspirates or scrapings • institutions for the intellectually Entamoeba histolytica is a protozoan obtained by proctoscopy disabled parasite that exists in two forms: an infective cyst and a potentially • aspirates of or other tissue • men who have sex with men specimens. pathogenic trophozoite. It should not be • travellers returning from developing confused with the morphologically Repeated stool specimens may be countries. identical non-pathogenic Entamoeba needed to establish a diagnosis as cysts Amoebiasis most commonly affects dispar. are shed intermittently in asymptomatic young adults and is rare below the age of and mild infections. The presence of five years. Amoebic is very Identification trophozoites containing red blood cells is Clinical features rare under the age of two years when indicative of invasive amoebiasis. Most infections are asymptomatic but dysentery is more commonly due to occasionally clinically important Serology using indirect Shigella. intestinal or extra-intestinal disease may haemagglutination (IHA) and enzyme Reservoir result. immunoassays (EIA) is useful in the diagnosis of extra-intestinal disease such Humans are often asymptomatic Intestinal disease varies from an acute as liver abscesses, when stool carriers. form with diarrhoea which may be bloody examination is often negative. Serology is and associated fever and abdominal Mode of transmission also important in the differentiation discomfort (amoebic dysentery) to mild Amoebiasis can be transmitted by: between strains of the pathogenic abdominal discomfort with diarrhoea E. histolytica and strains of the non- • ingestion of water contaminated with containing blood or mucus alternating pathogenic E. dispar. faeces containing amoebic cysts with periods of constipation or remission. X-ray, ultrasound and CT scans are also • ingestion after faecal contamination of Intestinal amoebiasis may rarely be useful in the identification of amoebic hands complicated by: abscesses and can be considered • contaminated raw vegetables • granuloma of the large intestine diagnostic in the presence of a specific • unprotected oral-anal sexual contact. • colonic perforation and haemorrhage antibody response to E. histolytica. Period of communicability • perianal ulceration. Incubation period Cases are infectious as long as cysts are The average incubation period is two to Dissemination via the bloodstream may present in the faeces. In some instances four weeks. Patients may present months lead to extra-intestinal amoebiasis. This cyst excretion may persist for years. is most commonly manifested as to years after the initial infection. formation in the liver. This can Susceptibility and resistance occur less commonly in the brain or All non immune people are susceptible lungs. to infection. People with E. dispar do not develop symptoms. Reinfection is possible but rare. 8 The blue book: Guidelines for the control of infectious diseases

Control measures Control of contacts Preventive measures Consider faecal screening for household General public health measures to members and institutional contacts. prevent disease transmission focus on: Faecal screening is advised for fellow travellers of a confirmed case. Confirmed • public education on the importance of carriers should also be treated. personal hygiene Control of environment • providing information to intending Environmental measures to control travellers about the risk involved in disease transmission focus on: eating uncooked vegetables and fruits and drinking contaminated water • protecting public water supplies from faecal contamination • public education about the possibility of transmitting the disease via sexual • investigation of the food preparation contact. practices of any implicated local food premises. Control of case Treating clinicians should consult the Outbreak measures current version of Therapeutic guidelines: In the event of a cluster of cases, public antibiotic (Therapeutic Guidelines health measures involve: Limited) and seek expert advice. Metronidazole and either diloxanide • confirmation of laboratory results furoate or paramomycin are the usual • undertaking an epidemiological treatment. Neither diloxanide furoate or investigation to determine source of paramomycin are registered for use in infection and common mode of Australia - contact the NPS Therapeutic transmission Advice and Information Service on • taking appropriate measures to 1300 138 677. eliminate any common vehicles of For amoebic liver abscess metronidazole transmission, such as contaminated should be continued for 14 days and food or water, to prevent further cases. specialist advice should be sought. Special settings Passage of Entamoeba cysts or Persons who are suspected of having trophozoites in the absence of acute acquired their infection in an institutional dysenteric illness does not warrant setting should be investigated as therapy. appropriate by the Department of Surgical aspiration of abscesses may be Human Services. necessary. Cyst eradication with diloxanide furoate may be indicated in Additional sources of information cyst carriers. Seek expert advice. • Centers for Disease Prevention and Control, Atlanta USA, http://www.cdc.gov/ncidod/ The blue book: Guidelines for the control of infectious diseases 9

Anthrax

Victorian statutory requirement Untreated cutaneous anthrax has a case Method of diagnosis Anthrax infection (Group A disease) must fatality rate of 5–20% but death is rare Laboratory confirmation of anthrax is be notified immediately by telephone or with early appropriate treatment. by demonstrating the presence of fax followed by written notification within Pulmonary (inhalational) anthrax B. anthracis in blood, lesions or discharges five days. This is very rare and often presents with by direct staining of smears using Gram or other special stains, or by isolation of the School exclusion is not required. mild and non-specific symptoms including fever, malaise and mild cough organism by culture or animal inoculation. Infectious agent or chest pain (upper respiratory tract Serological and nucleic acid testing are Bacillus anthracis is a gram-positive, symptoms are rare). Early symptoms may likely to be available in the near future aerobic rod-shaped bacterium that is be confused with a flu-like illness. from reference laboratories. encapsulated, spore-forming and non- This is followed within three to six days Incubation period motile. by rapid onset of hypoxia, dyspnoea and The incubation period is typically one day Identification high temperature, with radiological for cutaneous anthrax and one to seven Clinical features evidence of mediastinal widening. days for pulmonary anthrax. Evidence from Anthrax is an acute bacterial disease that Meningitis frequently occurs. mass exposures indicates incubation usually affects the skin. It may rarely The mortality rate approaches 100% with periods up to 60 days are possible for involve the lungs after inhalation or the delayed or no treatment. pulmonary anthrax, related to delayed intestinal tract after ingestion. Commencement of appropriate activation of inhaled spores. The incubation is typically three to seven days Cutaneous anthrax during the prodrome for the gastrointestinal form. This form accounts for over 95% of significantly decreases the mortality rate. anthrax cases. Lesions usually occur on Intestinal/oropharyngeal anthrax Public health significance exposed skin and often commence with These are very rare forms of anthrax in and occurrence itchiness. They pass through several developed countries but may occur in Anthrax is primarily a disease of stages: large outbreaks in developing countries herbivores. Humans usually become • papular stage following ingestion of meat from infected infected when they come into contact animals. • vesicular stage with a that often with infected animals or their products. becomes haemorrhagic In intestinal anthrax, gastro-intestinal Anthrax is primarily an occupational symptoms may be followed by fever, • eschar stage that appears two to six hazard for handlers of processed hides, septicaemia and death. Case fatality days after the haemorrhagic vesicle goat hair, bone products, wool and rates of 25–75% have been reported. dries to become a depressed black infected wildlife. It can also be scab (malignant pustule) which may In oropharyngeal anthrax, fever, neck contracted by contact with infected have surrounding redness and swelling due to , throat meat, for example in abattoir workers. extensive oedema (swelling). pain, oral ulcers and dysphagia may be New areas of infection in livestock may followed by severe local ulcers and Anthrax lesions are usually painless but develop through introducing animal feed swelling, septicaemia and death. Case pain may result due to surrounding containing bone meal. Cutaneous fatality rates are similar to the intestinal oedema. Untreated lesions can progress outbreaks sometimes occur in knackery form. to involve regional lymph nodes. An workers and those handling pet meat. overwhelming septicaemia can occur in Anthrax spores can persist in the soil of severe cases. certain tracts of land for years such as areas where carcasses of animals dying of anthrax are buried. 10 The blue book: Guidelines for the control of infectious diseases

Anthrax can also be used as a bio- • by intentional release of spores using a • Sterilise hair, wool or hides, bone meal warfare or bio-terrorism agent, most likely variety of aerosol devices including or other feed of animal origin prior to spread as an aerosol. Any new case mail-items. processing. should be assessed with this possibility Intestinal or oropharyngeal anthrax is Control of case in mind, particularly but not exclusively in caused by ingestion of anthrax The following treatment advice is to be cases of pulmonary anthrax. contaminated undercooked meat. There used as a guide only. Always consult the Reservoir is no evidence of transmission through current version of Therapeutic guidelines: the milk of an infected animal. antibiotic (Therapeutic Guidelines Spores may remain viable in Limited) and seek expert advice from an contaminated soil for many years. Dried The deliberate release of anthrax spores infectious diseases physician. or processed skins and hides of infected through contaminated letters in the USA animals may also harbour spores for in October 2001 resulted in 22 cases of Cutaneous/gastrointestinal anthrax years. anthrax, of which half were cutaneous • Ciprofloxacin, penicillin or doxycycline and half were pulmonary anthrax. are the drugs of choice, usually given Mode of transmission for 7–10 days in cutaneous anthrax. Cutaneous anthrax is usually Period of communicability The duration of therapy for introduced through a skin injury. It can There is no evidence of direct spread gastrointestinal anthrax is not well occur: from person to person. Articles and soil defined. contaminated with spores may remain • by contact with tissues of animals such • If the case is associated with a bio- infective for years. as cattle, horses, pigs and others dying terrorist attack involving aerosolised of the disease, or in processing after Susceptibility and resistance anthrax where the risk is high, death Recovery is usually followed by ciprofloxacin or doxycycline are • by contact with contaminated hair, prolonged immunity. recommended and should be given for wool, hides or products made from at least 60 days. Control measures them (Hide-porter’s disease) • For patients with signs of systemic Preventive measures • by contact with soil associated with involvement, extensive oedema, or • Immunise high risk persons, usually infected animals and contaminated lesions on the head or neck, antibiotics laboratory workers who are liable to bone meal used in some gardening should be administered intravenously, handle B. anthracis, with the cell-free products as for patients with pulmonary disease. vaccine giving annual boosters as • possibly by biting flies that have fed on recommended. Protection is likely to Pulmonary anthrax infected animals in some parts of the be greater against cutaneous The following recommendations were world but not seen in Australia. exposures than pulmonary exposures. developed in the USA following experience during the deliberate release Pulmonary anthrax (‘woolsorter’s The vaccine is not currently licensed of anthrax through the postal system in disease’) can occur: for use in the general community. 2001. • by inhalation of aerosolised spores in • Educate employees who are handlers • Recommended initial treatment of industries that inadvertently may deal of potentially infected articles in the pulmonary anthrax is an intravenous with contaminated tissues or products proper care of skin abrasions. multi-drug regimen of either such as tanning hides, processing wool • Ensure proper ventilation in hazardous ciprofloxacin or doxycycline along with or bone products, or by accident in industries and the use of protective one or more agents to which the laboratory workers clothing. organism is typically sensitive. The blue book: Guidelines for the control of infectious diseases 11

• Ciprofloxacin has been recommended farm is suspended. Appropriate samples Outbreak measures on the basis of in vivo (animal) are collected and tested at a laboratory. A single case of anthrax should be findings. It should be used in This can take 12–24 hours. If the case considered an outbreak and should be preference to doxycycline in cases occurs on a dairy farm, the dairy factory managed with great urgency. If one or where meningitis is suspected because is advised to suspend collection of milk more patients seem to have been of the lack of adequate central nervous until the case is investigated and Dairy infected in an unusual way, such as no system penetration by the latter. Food Safety Victoria is advised. evidence of exposure to infected animals • Bacteremic patients are often initially If an animal anthrax case is confirmed, or their products, a deliberate release of treated with an empiric multi-drug the affected property is quarantined, anthrax organisms must be considered. regimen which provides adequate potentially exposed stock vaccinated, If a focus of infection was identified or a therapy for B. anthracis and other dead animals buried and contaminated deliberate release of organisms is possible pathogens. sites disinfected. The quarantine is not suspected, outbreak control measures • After susceptibility testing and clinical released until occurrences of anthrax would include: cases have ceased and at least six improvement, the empiric regimen may • coordination with appropriate weeks have elapsed since the last round be altered. A penicillin-based antibiotic, emergency services including the of on the property. DPI staff such as amoxycillin or amoxycillin/ police force if required clavulanic acid may then be used to will liaise with knackeries, local veterinary • active case finding complete the course. practitioners, the dairy industry, health authorities, local government and • alerts for medical practitioners and • Treatment should be continued for 60 regional emergency services staff. hospitals days in all cases of pulmonary anthrax. Decontamination of environments • release of appropriate public Keys to successful management appear contaminated after a deliberate release information to be early institution of antibiotics and of anthrax spores requires full HAZMAT • control of contacts including field aggressive supportive care. Chest tube decontamination by appropriately drainage of the recurrent pleural workers involved in environmental protected trained personnel using strong control measures effusions, which are typically chlorine-based disinfectants. The risk of hemorrhagic, often leads to dramatic secondary aerosolisation is generally • environmental control measures. clinical improvement. thought to be very low, although spores Additional sources of information Control of contacts produced for bioterrorism may be • Australian Government Department of Although there is no person to person deliberately prepared to increase this Health and Ageing fact sheet, transmission, the Department of Human risk. Although the risk of anthrax can be http://www.health.gov.au Services will trace and follow-up anyone significantly reduced by environmental who may have been exposed to the decontamination measures, evidence • Centers for Disease Control and same source as the case, and it may be from deliberate release of anthrax spores Prevention, Atlanta USA, Public health recommended that they take in other countries suggests that emergency preparedness and prophylactic antibiotics. complete environmental response, http://www.bt.cdc.gov Control of environment decontamination of anthrax spores is If an animal anthrax case is suspected, it extremely difficult. should be reported to the Department of Primary Industries (DPI). Movement of animals and animal products from the 12 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 13

Ascariasis (round worm infection)

Victorian statutory requirement A. lumbricoides are often diagnosed on Mode of transmission Notification is not required. radiography either as worm shaped Transmission occurs when eggs are radiolucent areas in a barium filled School exclusion: exclude from school or swallowed from soil contaminated with intestine or in cholangiograms. children’s services centre if diarrhoea is human faeces or from uncooked produce Significant eosinophilia is noted in only present. contaminated with soil containing about 10% of cases. infective eggs. The eggs remain viable in Infectious agent moist soil for several months or years. Incubation period The infective agents are Ascaris The lifecycle requires four to eight weeks Transmission does not occur from direct lumbricoides, a large intestinal to complete. Ascaris eggs are person to person contact or from fresh roundworm (the female measuring up to unsegmented when passed and require a faeces. The eggs hatch in the small 30 cm in length) and Ascaris suum,a period of two or three weeks outside the intestine and larvae pass through the similar parasite primarily affecting pigs to develop to the infective stage. intestinal wall into the blood. They then and occasionally humans. Mature female worms have been pass to the liver and heart and to the lungs. In the lungs they have a further Identification estimated to produce an average of 200 period of development. Larvae then Clinical features 000 eggs per day. penetrate through the alveoli into the Many people have no symptoms and the Public health significance airways and migrate up to the pharynx to first indication of ascariasis may be the and occurrence be swallowed and reach their final passage of a worm by the anus, mouth or Ascariasis infects an estimated one destination in the small intestine. This nostril. The usual life cycle of the worm is billion people around the world, more occurs about 14–20 days after egg described below. Migration of the larval than any other parasitic infection. ingestion. Larvae then mature into adult forms of the worm can cause symptoms worms which mate. Females begin to lay due to various types of pneumonitis, liver Roundworm infections are common in eggs 45–60 days after initial egg damage or allergy. temperate or tropical regions of the world ingestion. including Australia. In communities Adult worms can cause a variety of where poor sanitary conditions exist abdominal symptoms and occasionally Period of communicability often 100% of the population will harbour serious complications such as intestinal Ascariasis is communicable as long as the parasite. obstruction or biliary disease. Ascariasis the mature fertilised female worm lives in aggravates malnutrition in The prevalence and intensity of infection the intestine. The usual life span is 12 underdeveloped countries. is usually highest in children aged three months however it has been reported to to eight years. Ascaris eggs are able to Method of diagnosis be as long as 24 months. survive for months in faecal matter, Diagnosis can be made by the sewage or even in a 10% formalin Susceptibility and resistance identification of eggs or the presence of solution. Infection does not infer immunity. adult worms in faeces. Pulmonary involvement may be confirmed by Reservoir Control measures identifying ascarid larvae in the sputum Ascaris eggs in soil or infected humans Preventive measures or gastric washings. act as reservoirs. Promote effective hand washing, particularly prior to preparing or consuming food. 14 The blue book: Guidelines for the control of infectious diseases

Control of case The usual treatment is albendazole, pyrantel or mebendazole. In mixed infections with Ascaris and other parasites it is important to initially use a drug that is effective against Ascaris, thereby reducing the chances of stimulating the worm into untoward activity. Consult the current version of Therapeutic guidelines: antibiotic (Therapeutic Guidelines Limited). When worms obstruct the pancreatic duct or migrate up the biliary tree, surgical or endoscopic removal of the worm may be necessary. Students with ascariasis should be excluded from school or child care if diarrhoea is present. Control of contacts Consider faecal screening of household members to determine if they also require treatment. No school or child care exclusion is required for contacts. Control of environment Environmental sources of infection should be investigated.

Outbreak measures Not applicable.

Additional sources of information Markell, E, John, D, Krotoski, W 1999, Markell and Voge’s medical parasitology, 8th edn, ed. Saunders. The blue book: Guidelines for the control of infectious diseases 15

Barmah Forest virus disease

Arboviruses are viruses which are spread most parts of mainland Australia, and Northern Territory and Victoria. by the bite of arthropods, particularly serological surveys indicate that it Outbreaks have been reported in Victoria mosquitoes. They are divided into causes widespread human infection. throughout the Murray Valley and the alphaviruses and flaviviruses. Gippsland areas. Identification Three infective alphaviruses include Ross Clinical features Reservoir River, Barmah Forest and Sindbis viruses. Features include fever, arthritis, arthralgia Like RRV, BFV disease appears after These all have the capacity to cause a and which are clinically heavy rains encourage the breeding of similar disease in humans characterised indistinguishable from RRV disease. Like mosquito vectors. It is not established, by fever, joint involvement and a rash. RRV disease there is a high subclinical but it is likely, that macropods and other Molecular studies of epidemiologically rate of infection and a low disease rate in marsupials are the principal hosts for the distinct isolates of Ross River and Sindbis children. Recovery usually occurs within virus. BFV antibodies have been found in viruses have shown changes in isolates several weeks but lethargy, arthralgia and kangaroos, cattle, horses and sheep on from different areas (distinct topotypes). myalgia can persist for over six months. the south coast of New South Wales. This may explain varying disease patterns Outbreaks of BFV disease sometimes which sometimes occur in certain occur concurrently with RRV disease Mode of transmission geographic locations and the differing making diagnosis difficult. BFV is transmitted by mosquitoes. Culex transmissibility of some strains by annulirostris is the major in inland Method of diagnosis different vector mosquitoes. areas and Ochlerotatus vigilax (New Serology shows a significant rise in South Wales) and Ochlerotatus antibody titre to the BFV. The virus may Victorian statutory requirement camptorhynchus in southern parts of be isolated from the blood of acutely ill Barmah Forest virus infection (Group B Victoria and Tasmania are the vectors in patients. Virological tests are necessary disease) requires notification in writing coastal regions. within five days of diagnosis. to distinguish BFV disease from other causes of arthritis. Period of communicability School exclusion is not required. Laboratory evidence requires one of the There is no evidence of transmission Infectious agent following: from person to person. Barmah Forest virus (BFV) was first • isolation of BFV from clinical material Susceptibility and resistance isolated in 1974 from Culex annulirostris • detection of BFV by nucleic acid Infection with BFV confers lifelong mosquitoes collected in the Barmah testing immunity. Forest near the Murray River in northern Victoria, and simultaneously from • a significant rise in IgG to BFV mosquitoes collected in southwest • detection of BFV-specific IgM. Queensland. It has also been isolated from numerous other mosquitoes Incubation period including the coastal species The incubation period appears to be Ochlerotatus vigilax (New South Wales) seven to ten days. and Ochlerotatus camptorhynchus (Victoria), which enjoy a salt marsh Public health significance habitat, and from the midge Culicoides and occurrence marksi in the Northern Territory. Since 1988, BFV disease has been Subsequently, BFV has been detected in reported in Western Australia, Queensland, New South Wales, the 16 The blue book: Guidelines for the control of infectious diseases

Control measures Outbreak measures Preventive measures • Conduct a community survey to BFV infection can be prevented by: determine the species of the vector • mosquito control measures mosquito involved. Identify their breeding places and promote their • personal protection measures such as elimination. long sleeves and mosquito repellents • Use mosquito repellents for persons • avoidance of mosquito-prone areas exposed to bites because of their and vector biting times at dusk and occupation, or other reasons. dawn. • Identify the infection among animal Control of case reservoirs, for example kangaroos, farm Second attacks are unknown. Treatment and domestic animals. is symptomatic with rest advisable in the acute stages of the disease. Presently, International measures there is no vaccine available Airport vector control in Australia and commercially to protect against BFV Papua New Guinea may be necessary to disease. prevent spread from areas to Control of contacts other countries where local vectors such Unreported or undiagnosed cases should as Aedes polynesiensis may transmit the be sought in the region where the patient disease. had been staying during the incubation Additional sources of information period of their illness. All family members • Boughton C R 1996, Australian should be questioned about symptoms Arboviruses of Medical Importance, A and evaluated serologically if necessary. handbook for general practitioners and Control of environment other clinicians, RACGP Services. To reduce or prevent virus transmission, interruption of human-mosquito contact is required by: • suppression of the vector mosquito population • avoidance of vector contact through personal protection and education. The blue book: Guidelines for the control of infectious diseases 17

Botulism

Victorian statutory requirement Method of diagnosis Mode of transmission botulinum infection (Group A Diagnosis is made by culture of Classical botulism is acquired by disease) must be notified immediately by C. botulinum or demonstration of specific ingestion of inadequately cooked food or telephone or fax followed by written toxin in serum, gastric aspirate, faeces, processed or refrigerated foods in which notification within five days. implicated food or wounds. toxin has formed, particularly canned and Electromyography may be useful in School exclusion is not required. alkaline foods. Most cases of wound corroborating the clinical diagnosis. botulism are due to ground-in soil or Infectious agent gravel. Several cases have been reported Incubation period Clostridium botulinum is a spore-forming amongst chronic drug users. Classical botulism occurs within 12–36 anaerobic bacillus. Several serotypes hours (sometimes several days) after botulism arises from ingestion of exist, however types A, B and E cause eating contaminated food. The spores rather than pre-formed toxin. most human disease. incubation period for infant botulism is Sources of spores include foods such as honey and dust. Honey has been Identification unknown due to difficulty in determining described in the US literature as a source Clinical features the precise time of ingestion. Shorter of infection but never implicated in There are three forms of botulism: incubation periods are associated with more severe disease and higher case- Australia and surveys of Australian honey • Classical botulism is a severe and fatality rates. have failed to identify C. botulinum. often fatal infection resulting from ingestion of contaminated food. Public health significance Period of communicability Symptoms include double vision, and occurrence Secondary transmission has not been dysphagia and dry mouth. It can be Botulism is a rare disease internationally. documented. followed by descending flaccid However missed diagnoses particularly Susceptibility and resistance which may be associated for intestinal botulism are likely due to Everyone is susceptible to infection. with respiratory paralysis and result in low clinician suspicion and limited death. Fever is absent unless a laboratory diagnostic capacity in many Control measures complicating infection occurs. areas. Preventive measures • Intestinal botulism is the most There have been only six cases of Ensure effective control of processing common form and usually affects botulism reported in Australia between and preparation of commercially canned under one year of age. It can 1991 and 2003. Two of these occurred in and preserved foods. affect adults who have altered Victoria in 2000 and 2001 Educate people undertaking home gastrointestinal anatomy and (Communicable Diseases Network canning and other food preservation microflora. The illness typically begins Australia - National Notifiable Diseases techniques about cooking time, pressure, with constipation followed by lethargy, Surveillance System). temperature, adequate refrigeration and listlessness, poor feeding, ptosis, C. botulinum has been identified as a storage. The absence of a bulging lid on difficulty in swallowing and generalised potential bioterrorist agent. tinned food does not preclude C. muscle weak-ness (‘floppy baby’). botulinum contamination. • Wound botulism is rare but has been Reservoir seen after contamination of wounds It is most commonly found in soil and where anaerobic conditions developed. agricultural products. Spores have been found in marine sediments and the intestinal tracts of animals, including fish. 18 The blue book: Guidelines for the control of infectious diseases

Control of case Control of environment Botulism is a medical emergency. Environmental health officers and food Suspected cases should immediately be safety officers should coordinate the referred for specialist care and trivalent appropriate disposal of implicated food. botulinum antitoxin (types A, B, E) administered as soon as possible. A Outbreak measures limited supply is available from CSL An outbreak of botulism is defined as Limited. Antitoxin is not used in infant one or more cases of disease. The botulism due to the risk of anaphylaxis. immediate aim is to identify possible Antibiotics do not affect the course of sources of the disease and other people the disease. possibly exposed. Recall any implicated food immediately and send samples to For wound botulism, in addition to the Microbiological Diagnostic Unit for antitoxin the wound should be debrided analysis. Take sera and faeces from or drained, and appropriate antibiotic cases as well as exposed but prophylaxis against other potential asymptomatic persons for analysis, infections should be administered. before administration of antitoxin. Isolation or quarantine is not needed but Undertake efforts to recover and test hand washing is indicated after handling implicated foods. This should be soiled nappies. Usual sanitary disposal of coordinated through Food Standards faeces from infant cases is acceptable. Australia New Zealand (02) 6271 2222. Any implicated food should be retained for collection and investigation by public health authorities. Contaminated utensils should be cleaned by boiling or with household bleach. Control of contacts Those who have eaten incriminated food should be purged with emetics, gastric lavage or high enemas. Administration of polyvalent antitoxin to asymptomatic individuals should be considered carefully, assessing potential protection against the risk of sensitisation and severe reactions to horse serum. The blue book: Guidelines for the control of infectious diseases 19

Brucellosis (undulant fever, Malta fever)

Victorian statutory requirement test (Rose Bengal and seroagglutination) Mode of transmission Brucellosis (Group B disease) must be detecting agglutinating antibodies (IgM, Brucellosis can be transmitted by notified in writing within five days of IgG and IgA) with others detecting non- contact with infected tissues, blood, diagnosis. agglutinating antibodies (Coombs-IgG or urine, vaginal discharges, aborted animal ELISA-IgG) developing in later stages. School exclusion is not required. foetuses and especially placentae. It can Except in the case of B. canis, where also be transmitted by ingestion of raw Infectious agent diagnosis requires tests detecting milk and dairy products from infected The following infectious agents cause antibodies to rough-lipolysaccharide animals. antigens. brucellosis: Outbreaks are generally attributed to • Brucella abortus (biovars 1–6 and 9) Incubation period inhalation of aerosols which may occur in • Brucella melitensis (biovars 1–3) The incubation period is highly variable. It animal pens and stables, abattoirs and laboratories, or through ingestion of • Brucella suis (biovars 1–5) is most commonly one to two months but ranges from five to sixty days. unpasteurised milk products. A small • Brucella canis number of cases have occurred following Public health significance accidental self-inoculation of the strain Identification and occurrence 19 animal Brucella vaccine. Clinical features B. abortus was successfully eradicated Brucellosis is a systemic bacterial from Australian cattle herds during the Period of communicability disease with acute or insidious onset. national eradication campaign in 1989. There is no evidence of communicability Localised suppurative infections may B. suis is still isolated occasionally from from person to person. occur. Subclinical and unrecognised feral pigs in Queensland and represents Susceptibility and resistance infections are frequent. a risk to people who hunt and butcher Everyone is susceptible to infection. Fever is the most common symptom and feral pigs. Notifications of brucellosis in Severity and duration of clinical illness may be associated with a variety of other Victoria are now rare and generally are subject to wide variation. Duration of complaints. represent imported infections or acquired immunity is uncertain. Osteoarticular complications are undiagnosed chronic infections. common. Orchitis, epididymitis, Brucellosis occurs worldwide. The Control measures osteomyelitis and endocarditis are less sources of infection and responsible Preventive measures common. The case-fatality rate in organism vary according to geographic Educate the public, particularly travellers, untreated brucellosis is approximately area. Affected regions include the against drinking unpasteurised milk or 2%, mostly due to endocarditis from Mediterranean countries, North and East eating dairy products produced from B. melitensis infections. Africa, Western Africa, the Middle East, such milk. Boiling milk is effective in killing the organisms when pasteurisation Method of diagnosis India and Central and South America. is not available. Laboratory confirmation of the diagnosis Reservoir is made by isolating the infectious agent Educate farmers and handlers of The most important reservoirs for human from blood, bone marrow, other tissues or potentially infected animals such as feral infection are cattle, swine, goats, sheep discharges of the patient. Serological pigs to reduce exposure and exercise and dogs. Infections may also occur in testing for Brucella is useful but often care in handling placentae, discharges other wild ungulates. difficult to interpret. Current serological and foetuses. Search for and investigate B. canis has occasionally been identified tests allow a precise diagnosis in over 95% livestock at risk of infection. in laboratory dogs. of cases, but it is necessary to combine a 20 The blue book: Guidelines for the control of infectious diseases

Control of case Treatment should be age appropriate. Consult the current version of Therapeutic guidelines: antibiotic (Therapeutic Guidelines Limited) and seek expert infectious diseases. Control of contacts Although there is no person to person transmission of brucellosis, contact tracing is done as part of the case investigation to identify those people who have been exposed to the same implicated source of Brucella infection as the case. These people are advised of the early of brucellosis to aid early diagnosis and treatment. Control of environment The Department of Primary Industries is notified of any new, non-imported case of brucellosis so that appropriate animal investigations and control measures can commence. All incriminated products are recalled. Restriction on the distribution of unpasteurised milk and milk products is enforced.

Outbreak measures Trace source of infection such as contaminated unpasteurised milk products and institute appropriate control measures.

Additional sources of information • Australian Quarantine and Inspection Service, www.aqis.gov.au • Victorian Department of Primary Industries, phone 136 186, www.dpi.vic.gov.au The blue book: Guidelines for the control of infectious diseases 21

Campylobacter infection

Victorian statutory requirement Incubation period Period of communicability Campylobacter infection (Group B The incubation period is usually two to Cases are infectious throughout their disease) must be notified in writing five days, with a range of one to ten days. illness. Excretion of organisms may within five days of diagnosis. continue for some weeks after symptoms Public health significance resolve. School exclusion: exclude cases from and occurrence child care and school until after Campylobacter infections are now the Susceptibility and resistance diarrhoea has ceased. most commonly notified of the enteric All non immune people are susceptible Laboratories are required to notify pathogens in Victoria and over 14 900 to infection. Immunity to serologically C. jejuni, C. coli or C. lari isolated from cases were reported Australia-wide in related strains may follow infection and water supplies or C. jejuni detected in 2003 (Communicable Diseases Network may be more common in high incidence food. Australia – National Notifiable Diseases regions. Surveillance System). The incidence of Infectious agent infection appears to be increasing, a Control measures The most common types of trend observed internationally. All age Preventive measures Campylobacter species that cause groups are affected. The most commonly Prevention is dependent on good infection are C. jejuni, C. coli, C. fetus, C. affected are children less than five years personal and food hygiene. Raw meats lari, and C. upsaliensis. of age and young adults. Most cases in should be cooked thoroughly and refrigerated after cooking, especially Identification Australia appear sporadic but food and water-borne outbreaks occur and it is poultry. Wash utensils used to prepare Clinical features raw meats and poultry in hot soapy Campylobacter infection may be likely that many outbreaks are not detected. water before using them to prepare non- subclinical or cause disease of variable cooked food such as salads. severity. C. jejuni infection typically Reservoir Unpasteurised milk and dairy products results in abdominal pain, fever and Many animals, especially birds, are should not be consumed. Recognise diarrhoea which may be mucopurulent or carriers of Campylobacter spp. Domestic pets as sources of infection and bloody. Symptoms usually last two to five animals are another possible source of encourage hand washing after handling days. infection. animals. Campylobacter infection has been Mode of transmission Control of case associated with rare sequelae including Treatment is largely symptomatic. Infection occurs most commonly by reactive arthritis and Guillain-Barré However, antibiotics may be indicated for ingestion of the organism via syndrome (polyneuritis). Human infection severe illness or where prompt contaminated foods, particularly raw or with C. fetus may cause localised termination of faecal excretion is desired. undercooked meats (especially poultry). abscesses or generalised sepsis Antibiotics are not indicated for Person to person transmission via the particularly in immunosuppressed diarrhoeal disease in which the causative faecal-oral route is common. Infection persons. pathogen is not known, except in some may also occur through contact with Method of diagnosis very severe illnesses when empirical infected animals. Infection is diagnosed by culture of treatment may be considered. Campylobacter spp. from faeces, blood or other clinical specimens. 22 The blue book: Guidelines for the control of infectious diseases

To prevent further transmission the importance of hand washing and personal hygiene should be stressed, particularly with respect to food preparation. Health care workers, child care workers, food handlers and children in school and child care centres should be excluded from work or school until diarrhoea has ceased. As asymptomatic excretion may persist, diligent personal hygiene is required. Isolation is not required for hospitalised patients and standard precautions apply. Control of contacts The diagnosis should be considered in symptomatic contacts. Investigate related cases to identify a common source. Control of environment Isolation is not required for hospitalised patients and standard precautions apply.

Outbreak measures Two or more related cases should be reported immediately, particularly in institutions. Obtain food histories and investigate other recognised vehicles of infection such as pets or farm animals to identify a common source. The blue book: Guidelines for the control of infectious diseases 23

Chickenpox or shingles (varicella/herpes zoster)

Victorian statutory requirement Complications include secondary Method of diagnosis Notification is not required. bacterial infection of the skin lesions, Confirmation of the diagnosis is generally primary varicella , aseptic School exclusion differs according to only required when the clinical picture is meningitis, encephalitis and Reye’s case or contact status: atypical. It is made by: syndrome (acute encephalopathy with • isolation of the virus in cell cultures • cases should be excluded until full fatty infiltration and dysfunction of the recovery or for at least five days after liver). • visualisation by electron microscopy the first eruption appears. Some Newborns and immunosuppressed • serological tests for antibodies remaining scabs are not a reason for patients are at greatly increased risk of continued exclusion • immunofluorescence on lesion swab or severe chickenpox. fluid • any child with an immune deficiency or Herpes zoster (shingles) receiving chemotherapy should be • nucleic acid testing or PCR. Herpes zoster or shingles is characterised excluded for their own protection. by a predominantly unilateral vesicular Incubation period Otherwise contacts are not excluded. eruption within a dermatome. It is often The incubation period is from two to Infectious agent associated with severe pain that may three weeks and is usually 14–16 days. Human herpesvirus 3 (alpha) or varicella precede lesions by 48–72 hours. The This may be prolonged in zoster virus (VZV) is the causative agent. rash lasts up to several weeks depending immunosuppressed persons or following on severity. The rash is often more immunoglobulin administration as Identification widespread and persistent in passive immunisation against varicella. Clinical features immunosuppressed patients. Varicella (chickenpox) Public health significance Patients must be carefully evaluated to Chickenpox generally presents with a and occurrence ensure that there is no eye involvement low-grade fever, malaise and a rash. The Chickenpox is a highly contagious but when the rash involves the ophthalmic rash is firstly maculopapular then generally mild disease and is endemic in area of the face. Specialist treatment is becomes vesicular (blistered) and the population. It becomes mandatory in this case as blindness can progresses to crusted lesions over about among susceptible individuals mainly result. five days. Lesions appear in three or four during winter and early spring. More than crops. They are most numerous on the Incidence increases with age and 90% of cases are children under 15 years trunk and less so on the face, scalp, children under 12 are rarely affected of age. limbs and mucous membranes of the unless immunosuppressed or infected as Herpes zoster (shingles) occurs in 20% of mouth. Some cases (about 5%) are infants. people, mostly when they are elderly due subclinical or exceedingly mild in nature. A debilitating complication of herpes to the reactivation of latent virus from the Adults tend to suffer with more severe zoster in many (especially elderly) dorsal root ganglia. disease than children. Rarely, the disease patients is prolonged pain (post-herpetic neuralgia) which may persist for months Reservoir may be fatal. Humans. after resolution of the skin lesions. 24 The blue book: Guidelines for the control of infectious diseases

Mode of transmission • immunosuppressed individuals Control of case Chickenpox transmission is mainly including those with haematological Varicella (chickenpox) person to person by airborne respiratory malignancies, on chemotherapy, high In the non-hospitalised patient with a droplets but also by direct contact with dose steroids or with HIV infection. normal immune system and vesicle fluid of chickenpox cases, or uncomplicated varicella, aciclovir is not contact with the vesicle fluid of patients Control measures recommended because the benefits are with herpes zoster. Indirect contact Preventive measures only marginal. In immunocompromised occurs through articles freshly soiled by In Australia, the varicella vaccine is patients with severe disease and in discharges from vesicles of infected recommended for non-immune, healthy normal patients with complications of persons. Scabs are not infective. individuals aged 12 months or older. varicella (such as pneumonitis or It provides protection against infection in encephalitis) aciclovir may be used. Period of communicability 70–90% of individuals. Consult the current version of It is usually communicable for one to two Non-immune individuals who should be Therapeutic guidelines: antibiotic days (up to five days) before the onset of specifically targeted for (Therapeutic Guidelines Limited). the rash, continuing until all the lesions include: General measures include: are crusted. Communicability may be prolonged in patients with altered • household contacts of • tepid bathing or cool compresses may immunity. immunosuppressed people help to alleviate itching Those with zoster are considered • health care workers • exclude from school until fully infectious for a week after lesions appear • those working with young children recovered, or at least five days after when they are moist. eruption first appears. Some remaining • women contemplating pregnancy scabs are not a reason for continued Susceptibility and resistance • parents of young children. exclusion Chickenpox is highly infectious, herpes Vaccination is contraindicated in • advise adults to stay away from work zoster much less so. Over 80% of non- immunosuppressed people and pregnant for the same period immune household contacts of a case of women. For further details see the chickenpox will become infected. Non- • avoid contact with high risk susceptible current edition of the Australian immune people exposed to shingles persons. immunisation handbook (National Health cases will develop chickenpox (not and Medical Research Council). Aspirin should never be given to children zoster) if they become infected. with varicella due to a strong association Immunosuppressed people and Second attacks of chickenpox are rare with the development of Reye’s newborns should be protected from but do occur. syndrome. exposure. If exposure has occurred in Infection remains latent and can recur these persons varicella zoster immune years later as shingles. globulin (VZIG) is effective in modifying Patients who are at high risk of severe or preventing the disease if given within disease/complications if they do not 96 hours of exposure. VZIG is available have immunity include: from the Australian Red Cross. • infants less than one month old • pregnant women The blue book: Guidelines for the control of infectious diseases 25

Herpes zoster (shingles) Any non-immune person admitted to limb hypoplasia and cortical atrophy of Some antiviral medications (famciclovir, hospital who has a known exposure to the brain. valaciclovir or aciclovir) have been shown varicella should be isolated during days Intrauterine infection can also result in to be effective for treatment of varicella 10–21 after exposure or up to 28 days if herpes zoster in infancy. This occurs in zoster infections in patients with a rash immune globulin given to reduce the risk less than 2% of infants. The highest risk is less than 72 hours old. It gives pain relief, of spread to immunosuppressed associated with infection in late accelerates healing and may be of patients. pregnancy. benefit in reducing the incidence of post- Special settings In the third trimester, maternal varicella herpetic neuralgia. The addition of School corticosteroids in selected patients may may precipitate the onset of premature Children with chickenpox are excluded labour. also speed resolution. for at least five days after the rash More intensive treatment is warranted in appears. A few remaining scabs are not a Severe maternal varicella and pneumonia high risk patients. Consultation with an reason for continued exclusion. Children at any stage of pregnancy can cause infectious diseases physician is advised. with shingles can attend school if the foetal death. Adequate analgesia should not be lesions can be covered adequately Susceptible pregnant women who have forgotten. however exclusion from swimming and been exposed during pregnancy should Control of contacts contact sports should be advised for seek specialist obstetric advice. They Significant contact is defined as face-to seven days after the rash appears. may be offered zoster immune globulin face contact for at least five minutes, Parents of children with (VZIG) and antivirals (famciclovir, being in the same room for greater than immunosuppressive diseases should be valaciclovir or aciclovir), especially where one hour or household contact. advised of cases of chickenpox in the delivery is imminent. Varicella vaccination school as they may wish to voluntarily Where chickenpox develops in Vaccination may be used to prevent or exclude their own child. pregnancy, early medical review within attenuate illness if given to susceptible Immunosuppressed and their 24 hours of rash onset is indicated to contacts within five days (preferably 72 household contacts consider treatment options. hours) of first exposure. Immunosuppressed people, in particular Newborns Varicella zoster immunoglobulin (VZIG) those with haematological malignancies, Where newborns develop varicella before High risk susceptible contacts where are at high risk of more severe infection. ten days of age or when maternal vaccination is not indicated such as VZIG should be offered to these patients chickenpox develops within seven days neonates, pregnancy and if exposed. Recommend vaccination of prior to delivery and up to 48 hours immunosuppressed persons should be susceptible household contacts of these postpartum, the neonatal fatality rate is offered varicella-zoster immune globulin patients. up to 30% without treatment. Treatment (VZIG) within 96 hours of exposure. If Pregnancy of mothers and of babies once born is vaccination is not contraindicated this Varicella infection during the first vital. should follow at least 3 months later. trimester of pregnancy confers a small Premature babies and infants less than (See the current edition of the Australian risk of . Maternal infection one month old who develop varicella immunisation handbook, National Health before 20 weeks may rarely result in the may require specific treatment. Seek and Medical Research Council, for foetal varicella zoster syndrome, with the expert advice. further details and supply.) highest risk (2%) occurring at 13–20 Contacts should not be excluded from weeks. Clinical manifestations include school. growth retardation, cutaneous scarring, 26 The blue book: Guidelines for the control of infectious diseases

Health care workers Outbreak measures On commencement at a new workplace Timely vaccination of susceptible all health care workers with an uncertain contacts is indicated to contain an history of varicella infection should be outbreak. serotested and offered immunisation if susceptible. Additional sources of information • Australasian Society for Infectious If a rash develops in the three weeks Diseases 2001, ‘Position statement on after immunisation, the worker should be management of varicella-zoster virus removed from patient contact until exposure and infection in pregnancy varicella is excluded or lesions have and the newborn period’, Medical crusted over. Journal of Australia, vol. 174, pp. If a health care worker is exposed to a 288–291. confirmed case of varicella or herpes zoster they may continue working with patient contact if they have a history of previous infection or immunisation. They should be advised to report any febrile symptoms or rash developing within three weeks of exposure and then avoid patient contact until varicella is confidently excluded. If the worker is susceptible and has been exposed, vaccination within five days of exposure is indicated. They should report rash occurring within six weeks of vaccination and avoid patient contact as above. If vaccination is refused, no patient contact should take place between days 10–21 after first exposure. Shingles in a health care worker Workers should not care for high risk patients until lesions have crusted over. Other patients can be cared for as long as lesions can be adequately covered. The blue book: Guidelines for the control of infectious diseases 27

Chlamydia (genital infection)

Victorian statutory requirement Complications and sequelae may result The choice of test depends on the Chlamydia (Group C disease) must be in chronic pelvic pain, infertility and specimen type submitted, the cost of the notified in writing within five days of ectopic pregnancy. Infections during test, the sensitivity and specificity of the diagnosis. pregnancy may cause preterm rupture of test and the expertise and size of the the membranes and preterm delivery. It laboratory. Specific information must be notified can also cause conjunctivitis in the under the Health (Infectious Diseases) newborn and pneumonitis in the young Incubation period Regulations 2001. To maintain infant. The incubation period is poorly defined confidentiality, only the name code (first but is probably 7–14 days or longer. two letters of the surname followed by The primary presentation of chlamydial the first two letters of the first name) is infection in males is urethritis but Public health significance required. A questionnaire is sent to the infection may be asymptomatic. Possible and occurrence diagnosing doctor to collect additional sequelae and complications of male Infection with C. trachomatis has information on the case that is essential urethral infection are epididymitis, become a major public health problem for detecting disease trends and infertility, Reiter’s syndrome and because of the long term consequences informing policy development. conjunctivitis. Receptive anal intercourse of infection experienced predominantly in men who have sex with men (MSM) Medical practitioners have a statutory by women. These include chronic pelvic may result in chlamydial proctitis. obligation under the Children and Young pain, ectopic pregnancy and infertility. Person’s Act 1989 to notify the Method of diagnosis Rarely males may also become infertile. Department of Human Services’ Child Testing individuals at high risk of Chlamydia is the most commonly Protection Service if they believe a child chlamydial infection is recommended. notified sexually transmissible bacterial is in need of protection on the basis of High risk individuals include those with a disease in Victoria. It affects both sexual abuse. clinical presentation suggestive of genders. The annual number of notified chlamydial infection, individuals cases has more than doubled since the Infectious agent attending general practitioners for testing early 1990s. Approximately 75% of Chlamydia trachomatis serogroups D–K of sexually acquired infection (STI), those infections are notified from individuals cause disease. attending STI and family planning clinics aged less than 30 years. and gay men’s health centres and Identification The prevalence of chlamydial genital partners of those already diagnosed with Clinical features infections in Australia has not been an STI. Most women with urethral or comprehensively established but it has endocervical chlamydial infection are Laboratory investigations currently been estimated to be 2.5 –14% in STD asymptomatic. Clinical manifestations available are: clinic patients, 5% in family planning may include vaginal discharge, dysuria • cell culture (only in specialised clients and up to 15% in commercial sex and post-coital or intermenstrual laboratories) workers. bleeding. Less frequent manifestations • antigen assays including direct While the spontaneous cure rate has include urethral syndrome (dysuria and immunofluorescence or enzyme been estimated at 7.4%, immunity pyuria), bartholinitis, perihepatitis and immunoassay following infection is thought to be type- proctitis. specific and only partially protective. As • hybridisation assays such as the DNA a result recurrent infections are common. probe • amplification assays including PCR and ligase chain reaction (LCR). 28 The blue book: Guidelines for the control of infectious diseases

Risk factors for chlamydial infections Control of case sequelae’, American Journal of include a relatively high number of sexual Azithromycin or doxycycline are used as Obstetrics and Gynecology, vol. 164, partners, a new sexual partner and lack first line to treat no. 6, pt. 2, pp. 1771–81. of use of barrier contraceptive measures. chlamydial infection. Advice on the • Centers for Disease Control and Endocervical C. trachomatis infection treatment of chlamydial infections can Prevention 2002, ‘Sexually transmitted has also been associated with an be found in Therapeutic guidelines: diseases treatment guidelines 2002, increased risk of acquiring human antibiotic (Therapeutic Guidelines Morbidity and Mortality Weekly Report, immunodeficiency virus (HIV) infection Limited) and the National management vol. 51 (RR06), pp.1–80, and may also increase HIV guidelines for sexually transmissible http://www.cdc.gov/mmwr infectiousness. infections (Venereology Society of Victoria, 2002). • Garland, SM, Gertig, DM & McInnes, JA Reservoir 1993, ‘Genital Chlamydia trachomatis Specialist consultation should be sought infection in Australia’, Medical Journal Humans. for complicated or disseminated of Australia, vol. 159, pp. 90–6. infections. Mode of transmission • Genc, M & Mardh, A 1996, ‘A cost- Transmission of C. trachomatis occurs Control of contacts effectiveness analysis of screening and primarily by sexual contact. Mother to Sexual partners of individuals with treatment for Chlamydia trachomatis baby transmission occurs when mothers chlamydial infection should be examined infection in asymptomatic women’, colonised with C. trachomatis infect and investigated then treated empirically. Annals of Internal Medicine, vol. 124, their babies as they are born vaginally. Contact tracing assistance can be no. 1, pt. 1, pp. 1–7. A high proportion of infections in women provided by the Department’s partner • Pearlman, MD & McNeeley, SG 1992, are asymptomatic resulting in untreated notification officers (03) 9347 1899. ‘A review of the microbiology, disease, ongoing transmission and an Control of environment immunology, and clinical implications increased risk of sequelae. Not applicable. of Chlamydia trachomatis infections’, Obstetrical and Gynecological Survey, Period of communicability Outbreak measures vol. 47, no. 7, pp. 448–61. The period of communicability is Not applicable. unknown but may be months to years. • Venereology Society of Victoria 2002, Additional sources of information National management guidelines for Susceptibility and resistance • Australian Government Department of sexually transmissible diseases, Everyone is susceptible to infection. Health and Family Services 1997, Venereology Society of Victoria, Contact tracing manual – a practical http://www.mshc.org.au Control measures handbook for health care providers • Victorian Department of Human Preventive measures managing people with HIV, viral Services 2001, Chlamydia strategy for Preventive measures include education hepatitis, other STDs and HIV-related Victoria 2001–2004, Victorian about safe sex practices including use of tuberculosis, Australian Government Department of Human Services. condoms and early detection of infection Department of Health and Family by testing of those at risk. • Weinstock, H, Dean, D & Bolan, G Services. 1994, ‘Chlamydia trachomatis • Cates, W & Wasserheit, JN 1991, infections’, Infectious Disease Clinics of ‘Genital chlamydia infections: North America, vol. 8, no. 4, pp. epidemiology and reproductive 797–819. The blue book: Guidelines for the control of infectious diseases 29

Chlamydophila pneumoniae

Victorian statutory requirement chlamydial species. A single antibody Asymptomatic carriage occurs in 2–5% Notification and school exclusion are not titre is of little diagnostic value on its of the population. Only about 10% of required. own as the seroprevalence of infections result in pneumonia. antibodies to C. pneumoniae of respiratory illness can Infectious agent approaches 50% in the adult occur and these usually occur in The infectious agent is Chlamydophila population. Seroconversion may take institutional settings such as military pneumoniae, an obligate intracellular up to eight weeks in an initial infection barracks or nursing homes. bacterium (previously named Chlamydia but it tends to occur much more Speculation regarding the bacteria’s pneumoniae). quickly in reinfection (one to two involvement in the pathogenesis of weeks). False positive antibody tests Identification atherosclerotic arterial disease can occur in the presence of a positive Clinical features continues. Seroepidemiologic studies rheumatoid factor. Chlamydophila pneumoniae infection is have shown an association between often mild. The initial infection appears to • Culture of nasopharyngeal aspirates, evidence of C. pneumoniae infection and be the most severe with reinfection often throat swabs or bronchial lavage fluid is atherosclerosis but the significance of asymptomatic. A spectrum of illness possible. Swabs should be placed in this is not yet established. Studies are from pharyngitis and sinusitis to chlamydia transport medium whilst ongoing into the effect of prophylactic pneumonia and bronchitis may occur. other specimens can be collected in antibiotic treatment on prevention of Sometimes there is a biphasic illness the usual containers. All samples atherogenesis. with initial upper respiratory tract should be kept refrigerated. Possible links with Alzheimer’s disease, infection symptoms which resolve and Diagnosis by PCR is available through the arthritis and asthma are also postulated. then a dry cough and low grade fever. Victorian Infectious Diseases Reference Reservoir The organism may be an infectious Laboratory (VIDRL) but it is currently only Humans. precipitant of asthma and is implicated in being used in investigation of outbreaks of respiratory illness where conventional about 5% of episodes of acute bronchitis. Mode of transmission testing has not revealed the cause of Cough occasionally persists for some Transmission occurs person to person infection. weeks despite appropriate antibiotic via respiratory secretions. therapy. Incubation period Period of communicability Method of diagnosis The incubation period is approximately Asymptomatic carriers may be an Chest X-ray may show small infiltrates. 21 days. Most cases of pneumonia are mild but important source of infection. the illness can be severe in otherwise Public health significance Symptomatic patients can carry the debilitated patients. C. pneumoniae is emerging as a frequent bacteria in the nasopharynx for months cause of both upper and lower after illness. Laboratory diagnosis is made with respiratory tract infections. It appears to serology or culture: be a common cause of mild pneumonia, • Serological diagnosis is made by especially in school age children. Up to detecting a four fold rise in antibody 10% of cases of community-acquired titre using microimmunofluorescence pneumonia can be attributed to this (MIF). MIF is the only serological test organism. that can reliably differentiate 30 The blue book: Guidelines for the control of infectious diseases

Susceptibility and resistance Everyone is susceptible to infection, with the risk of clinical disease increasing in patients with a chronic medical condition. Immunosuppressed patients do not seem to be more susceptible, but older debilitated patients may develop severe disease. Initial infection occurs in school-age children with up to 50% of the population becoming seropositive by 20 years of age. Infection does not produce complete immunity and reinfection can occur.

Control methods Control of case Mild to moderate infections are generally treated with roxithromycin or doxycycline. Consult the current version of Therapeutic guidelines: antibiotic (Therapeutic Guidelines Limited). Patients being managed in the community should be reviewed after 24 hours to assess treatment response. Therapy may need to be continued for up to 14 days. Isolation is not necessary, but the patient should be counselled on good respiratory hygiene, such as coughing into disposable tissues. Special settings Institutions Avoid crowding in living and sleeping quarters. The blue book: Guidelines for the control of infectious diseases 31

Cholera

Victorian statutory requirement Method of diagnosis person to person contact is rare. Cholera (Group A disease) must be The diagnosis is confirmed by the notified immediately by telephone or fax isolation of V. cholerae serogroup O1 or Period of communicability followed by written notification within five O139 from faeces. A presumptive Persons are infectious during the acute days. diagnosis can be made by visualisation stage and for a few days after recovery. by dark field or phase microscopy of By the end of the first week 70% of Cholera is subject to Australian V. cholerae’s characteristic motility, patients are non-infectious. By the end quarantine. specifically inhibited by preservative-free of the third week 98% are non-infectious. Infectious agent serotype-specific antiserum. Occasionally the carrier state may persist for months and chronic biliary infection serogroups O1 or O139 Incubation period with intermittent shedding of organisms cause cholera. The incubation period is from a few may last for years. Note hours to five days. It is usually two to Non-O1 Vibrios, formerly known as non- three days. Susceptibility and resistance agglutinable Vibrios (NAG) or non-cholera Even in severe epidemics, clinically Vibrios (NCV) are now included in the Public health significance apparent disease rarely occurs in more species Vibrio cholerae, but the reporting and occurrence than two per cent of those at risk. of Non-O1 or O139 infections as ‘cholera’ Cholera can occur in epidemics or Gastric achlorhydria increases risk of is inaccurate. . In any single epidemic one disease. There is some evidence that Most non-O1/O139 strains do not particular biovar tends to predominate. reduces the risk of secrete enterotoxin but can cause Endemic cholera occurs in parts of infection. Infection results in a rise in . The term non-Vibrio Africa, Central Europe and Asia. Cholera antibodies with increased resistance to cholera (NVC) refers to cases of cholera- appears to be increasing worldwide in reinfection. Infection with an O1 strain like illness caused by organisms other both the number of cases and their does not confer immunity against O139 than the 01 or 0139 Vibrio species. These distribution. Only sporadic imported strains and vice-versa. infections are not notifiable. cases in returned travellers occur in Victoria. V. cholerae O1 is established in Control measures Identification the riverine environment in some parts of Preventive measures Clinical features Queensland and New South Wales Travellers to endemic areas should be Asymptomatic infection with however human disease is rare. advised on careful food and water V. cholerae is more frequent than clinical consumption and personal hygiene. illness and bacteria may be present in Reservoir Travellers to endemic areas should carry faeces for 7–14 days. Mild cases of V. cholerae is often part of the normal oral rehydration powder available from diarrhoea are common especially among flora of brackish water and estuaries and pharmacies which must be reconstituted children. can be associated with algal blooms with boiled or sterilised water. (plankton). Humans are one of the In severe cases disease is characterised Cholera vaccine is a heat-killed reservoirs of the pathogenic form of V. by a sudden onset of symptoms with suspension of the Inaba and Ogawa cholerae. profuse painless watery (rice water) serotypes of V. cholerae O1. It provides stools, occasional vomiting, rapid Mode of transmission partial protection (approximately 50%) for three to six months. It is not routinely dehydration, acidosis and circulatory Transmission occurs through ingestion of recommended and advice to overseas collapse. In untreated cases, death may contaminated water and food. Sudden travellers should emphasise careful occur in a few hours and the case fatality large outbreaks are usually caused by a selection of food and water rather than rate may exceed 50%. contaminated water supply. Direct 32 The blue book: Guidelines for the control of infectious diseases

immunisation. Officially, cholera Control of contacts Outbreak measures vaccination certificates are no longer Contacts should be observed for five A single case of cholera in a person with required by any country or territory. days from the date of last exposure. This a history of no overseas travel is Unofficially, some countries may still may include all fellow travellers of a case. considered an outbreak. Initiate a require such a certificate, in which case Stool culture of any contacts with thorough investigation to determine the a single dose of cholera vaccine would symptoms of diarrhoea and stool culture vehicle and circumstances of satisfy this requirement. of all household contacts, even if transmission and plan control measures Control of case asymptomatic, should be undertaken. accordingly. Educate the population at Cholera is subject to quarantine Cases should also be looked for among risk about the need to seek appropriate conditions under the Commonwealth those possibly exposed to a common treatment without delay. Adopt Quarantine Act 1908. source. Immunisation of contacts is not emergency measures to assure a safe indicated. water supply. Ensure careful supervision Prompt fluid therapy with adequate of food and drink preparation. volumes of electrolyte solution such as Control of environment Gastrolyte is critical as life-threatening Severely ill patients should be isolated in Immunisation of contacts is not dehydration may rapidly occur. This is hospital, with standard precautions. Less indicated, even in the epidemic situation. usually all that is required for mild to severe cases can be managed at home. International measures moderate illness. Patients with severe Disinfection of linen and articles used by Reporting of cholera to the World Health dehydration require urgent intravenous the patient is required. Faeces and Organization is mandatory under fluid. Antimicrobial agents to which the vomitus can be disposed of into the toilet international health regulations. This will strain is sensitive shorten the duration of without preliminary disinfection, except in be done by the Department of Human diarrhoea and the duration of Vibrio areas with an inadequate sewage Services through the Australian excretion. disposal system. Terminal cleaning of hospital rooms and equipment is Government. Investigate possible sources of infection, required. particularly if there is no history of travel Additional sources of information to an endemic region. In cases with no history of overseas • Quarantine Act 1908, travel, urgent investigation of potentially http://www.austlii.edu.au contaminated food and water supplies is • World Health Organization, indicated. http://www.who.int/csr The blue book: Guidelines for the control of infectious diseases 33

Creutzfeldt-Jakob disease (CJD)

Victorian statutory requirement symptoms such as dysarthria. With Public health significance CJD (Group B disease) must be notified disease progression there may be and occurrence in writing within five days of diagnosis. pyramidal or spinal cord involvement, Since 1986 over 180 000 cases of BSE in muscle atrophy or fasciculations and School exclusion is not applicable. cattle have been reported in the UK. frequently myoclonus. Survival beyond Other countries have reported BSE in Infectious agent one year is unusual with death ensuing cattle imported from the UK. The rates of The infectious agent is a unique after a median of 4.5 months. BSE are now decreasing. BSE has not abnormal prion protein, designated as Variant CJD been reported in Australian cattle. Over PrP. This protein is an insoluble, protease- Variant CJD (vCJD) was first described in 100 cases of human vCJD have now resistant amyloid form of a normal the United Kingdom in 1996. The disease been reported in Britain. cellular protein designated PrPc. PrP acts is strongly linked to the consumption of No cases of vCJD have been reported in on normal prions, causing them to cattle products infected with the prion Australia. Classical CJD continues to change into the abnormal infectious form protein that causes bovine spongiform occur, with about 20 cases reported in a cascade like manner. encephalopathy (BSE), or mad cow annually. disease. There are clinical differences Identification between vCJD and cCJD. vCJD affects Reservoir Clinical features younger people (average 29 years) and Prion disease is present in cattle (BSE), CJD belongs to a group of rare diseases the duration of illness is longer (median sheep, goats, mink, mule deer and elk, known to affect humans and animals 14 months). Unlike cCJD, it commonly cats and exotic zoo animals. called transmissible spongiform begins with psychiatric symptoms such Transmission of variant CJD in humans encephalopathies (TSE). CJD presents in as depression and anxiety. Involuntary has only been linked to the consumption humans in either a classical or a variant movements and sensory symptoms such of meat and meat products from cattle form. as pain are usually present. with BSE. Classical CJD Method of diagnosis Infected humans with variant CJD and Classical CJD (cCJD) is one of four rare Diagnosis is suspected by the clinical classical CJD are potential sources of prion diseases that affect humans. The presentation, disease progression and infection for other humans by iatrogenic others are Kuru, Gerstmann-Straussler- exclusion of other causes. EEG and MRI means. Scheinker disease and fatal familial scans yield distinct results between insomnia. Mode of transmission classical and variant CJD. CSF tests The majority of cases of cCJD appear to Classical CJD occurs in sporadic, familial assist diagnosis. Definitive diagnosis is occur spontaneously with no source and iatrogenic forms. Sporadic cases usually made by brain biopsy or at identified. In very rare cases account for 85–90% of CJD cases and autopsy by detection of the PrP and transmission of cCJD has occurred have an unknown cause. Familial cases demonstration of the typical pathological through iatrogenic means. This has make up 5–10% and are associated with spongiform changes in the brain. included direct or indirect contact with a genetic mutation. Less than 5% are However, the diagnosis can also be brain tissue and cerebrospinal fluid. iatrogenic. confirmed by the detection of PrP in The symptoms of classical CJD usually other human tissue such as tonsillar For example, corneal or dural grafts or begin at an average age of 65 years. tissue by biopsy. injections of contaminated pituitary Most cases occur between 45 and 75 hormone obtained from cadavers. Incubation period years. The onset is commonly a rapidly Growth hormone is now made artificially. The incubation period is difficult to progressing dementia, however one third There is no evidence of risk to people in ascertain and varies from 15 months up of people may present with cerebellar close casual contact with a person to 30 years in iatrogenic cases. infected with CJD. 34 The blue book: Guidelines for the control of infectious diseases

Variant CJD is believed to be transmitted • a ban on blood products from people Control of contacts to humans through consumption of who have lived in the UK for six months Individuals who have may have shared a cattle infected with BSE. or more since 1980 until 1996, common exposure with a case or who There have been no cases of vCJD linked commenced in 2000 may have been exposed to infected to the receipt of infected blood products. • surveillance for vCJD by the Australian material from a case, such as As there is a theoretical risk of infection National CJD Registry based at the transplanted tissue, should be counselled from blood products, blood donors are University of Melbourne by a specialist infectious diseases physician. screened with respect to their possible • active surveillance of cattle for BSE by exposure in areas affected by vCJD, the Australian Government Control of environment particularly the United Kingdom. Department of Agriculture, Fisheries All wound drainage, tissues and surgical and Forestry. equipment should be considered to be Period of communicability contaminated. See also Control of case, The central nervous system tissues are Control of case above. These should be terminally infectious during symptomatic illness of There is no specific treatment except for disposed of or inactivated CJD. supportive care. (see Appendix 3). Animal studies suggest that the lymphoid Hospitalised patients should be managed The World Health Organization has and other organs are probably infectious using standard precautions. Tissues, advised that no part or product of any long before symptoms develop. surgical instruments and all wound animal which has shown signs of a TSE drainage should be considered should enter a human or animal food Susceptibility and resistance contaminated and must be inactivated. chain. Genetic mutations have been found in The PrP is very resistant to destruction familial CJD. Genetic susceptibility also by normal methods including standard Outbreak measures occurs for vCJD for humans who are sterilisation and because of this In the event of cases of vCJD being homozygous for methionine at codon129 instruments used on CJD patients, detected in Australia the Australian of the prion gene. particularly in surgery involving the brain, Government Department of Health and spine or eye, may need to be destroyed. Ageing with the Chief Medical Officer will Control measures coordinate the national response in Preventive measures It is important to obtain an accurate consultation with the State and Territory Precautionary measures instituted in history of travel, any previous surgical or health departments, and in consultation Australia to reduce the risk of vCJD dental procedures, and any history of with animal health authorities. importation include: exposure to human growth hormone or transplanted tissue. • a ban on the importation of beef and International measures beef products from the UK since 1996. If there is no travel history, obtain details See Outbreak measures, above. Extended to other affected European of any past procedure or surgery. International advisories and human and countries Inform the Australian Government animal quarantine issues are the • monitoring and restriction by the Department of Agriculture, Fisheries and responsibility of various Australian and Therapeutic Goods Administration Forestry to monitor Australian cattle if de State Government departments. (TGA) of the source of materials of novo vCJD occurs. animal origin used in the manufacture of medicines and medical devices The blue book: Guidelines for the control of infectious diseases 35

Additional sources of information • Turner, M 2001, ‘Variant Creutzfeldt- • Australian Government Department of Jakob disease and blood transfusion’, Health and Ageing 2003, ‘How Current Opinion in Hematology, vol. 8, Australia will respond to our first case of no. 6, pp. 372–379. vCJD. A guide for the public’, • World Health Organization 2002, www.health.gov.au Variant Creutzfeld-Jakob Disease - • Australian Government Department of fact sheet 180, www.who.int Agriculture, Forestry and Fisheries, www.affa.gov.au • Brown, P 2001, ‘Bovine spongiform encephalopathy and variant Creutzfeld- Jakob disease’, British Medical Journal, vol. 322, no. 7290, pp841–844. • Creutzfeld-Jakob Disease Foundation Inc, www.cjdfoundation.org • Coulthart, M, Cashman N 2001, ‘Variant Creutzfeldt-Jakob disease: a summary of current scientific knowledge in relation to public health’, Canadian Medical Association, vol. 165. • Health Canada Online 2003, Classical Creutzfeld-Jakob disease, www.hc-sc.gc.ca • National Institute of Neurological Disorders and Stroke 2003, Creutzfeldt-Jakob disease fact sheet, Bethesda USA, www.ninds.nih.gov • Smith, P 2003, ‘The epidemics of bovine spongiform encephalopathy and variant Creutzfeld-Jakob disease: current status and future prospects’, Public Health Reviews, Bulletin of the World Health Organization, vol. 81, no. 2. • Therapeutic Goods Administration (for specific TGA measures to minimise the risk of exposure to TSEs through medicines and medical devices), www.tga.health.gov.au 36 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 37

Croup or bronchiolitis

Victorian statutory requirement Bronchiolitis underlying cardiac or pulmonary disease Notification and school exclusion are not A one to seven day prodrome of mild or compromised immune systems are at required. fever, coryza and cough is common with increased risk for serious complications bronchiolitis. Disease can rapidly of RSV infection, such as pneumonia and Infectious agent progress to deepening cough, death. RSV infection among recipients of Respiratory syncytial virus (RSV), tachypnoea, restlessness, chest wall bone marrow transplants has resulted in parainfluenza viruses and adenoviruses retraction, nasal flaring and grunting. high mortality rates. Symptomatic RSV are the causative agents. Audible wheezing is a characteristic disease can recur throughout life Parainfluenza type 1 virus is the most feature. It can be accompanied by because of limited protective immunity common cause of croup and RSV the paroxysms of coughing, vomiting, induced by natural infection. most common cause of bronchiolitis. dehydration, otitis media and diarrhoea. Reservoir Method of diagnosis Identification Humans. The diagnosis of croup and bronchiolitis Clinical features is usually based on characteristic clinical Mode of transmission Disease is generally characterised by findings. Serologic diagnosis can be RSV is transmitted via oral contact, fever and one or more systemic reactions unreliable. Identification of the specific droplet spread or by contact with hands such as chills, headaches, generalised viral agent may be accomplished by or soiled by respiratory aches, malaise and anorexia. isolation in tissue culture from throat, discharges from an infected person. Gastrointestinal disturbances may also tracheal and nasal wash specimens, or occur. In babies and young children by multiplex PCR. Period of communicability general features are often not apparent RSV is communicable shortly prior to and and disease presents with localising Incubation period for the duration of active disease. signs at various sites in the respiratory The incubation period varies from one to Prolonged shedding of RSV has been tract. ten days. documented. Croup Public health significance Croup (laryngotracheobronchitis) has a Susceptibility and resistance and occurrence prodrome of fever, runny nose and sore Everyone is susceptible to infection. There is limited data on the epidemiology throat. Cough is also common. Reinfection with the agents that cause of croup and bronchiolitis in Australia. Inflammation at the subglottic level croup is common but the infection is Croup is more common in autumn and produces a classic high-pitched generally milder. affects children aged three months to inspiratory stridor and a hoarse voice. three years. It peaks in the second year Control measures The larger airways are narrowed by of life. Bronchiolitis is more common in Preventive measures inflammation resulting in various degrees winter and predominantly affects children There is no vaccine available. Basic of shortness of breath and increased in the first year of life. hygiene can help limit the spread of respiratory rate. Airway obstruction can many diseases including croup and progress with in-drawing of the Lower respiratory tract infections due to bronchiolitis. intercostal spaces and the soft tissues of viral agents are significant causes of the neck, cyanosis and death without infant and childhood morbidity and urgent treatment. mortality worldwide. Persons with 38 The blue book: Guidelines for the control of infectious diseases

Control of case Children with these diseases should not attend school or child care centres while unwell. Investigations are generally not indicated but may be useful in outbreak situations. Control of contacts Investigation of contacts is not necessary but the diagnosis in other family or close contacts should be considered if they are symptomatic. Control of environment Not applicable.

Outbreak measures Public health action is dependant on the setting in which the case has occurred and is based on an assessment of ongoing risk. The risk for nosocomial transmission of RSV increases during community outbreaks. Nosocomial outbreaks of RSV can be controlled by adhering to contact and respiratory precautions.

Additional sources of information • Centers for Disease Control and Prevention, Atlanta USA, Respiratory syncytial virus infection, http://www.cdc.gov/ncidod The blue book: Guidelines for the control of infectious diseases 39

Cryptococcal infection (cryptococcosis)

Victorian statutory requirement Public health significance and disorders of the reticuloendothelial Notification and school exclusion are not and occurrence system, particularly Hodgkin’s disease required. Human infection is rare in the absence of and sarcoidosis. immunosuppression. Persons at Infectious agent increased risk of infection include Control measures Cryptococcus neoformans,an patients with impaired immunity due to Preventive measures encapsulated yeast-like fungus. There are HIV/AIDS infection, corticosteroid No vaccine is available. Some patients two principal variants: therapy, lymphoma or sarcoidosis. may require maintenance antibiotics to C. neoformans var. neoformans prevent repeat infections (see below). Cryptococcal infections occur (serotypes A & D) and C. neoformans var. sporadically in all parts of the world. Control of case gattii (serotypes B & C). Adults are more commonly infected with Clinicians should consider referral to a specialist centre for treatment. Typical Identification males more commonly infected than treatment often involves amphotericin or Clinical features females. flucytosine. Cryptococcal infection usually presents Reservoir as sub-acute or chronic Patients with HIV/AIDS may require Cryptococcus has saprophytic growth in meningoencephalitis with headache and continuing maintenance therapy the external environment. altered mental state. Lung involvement (secondary prophylaxis), typically C. neoformans var. neoformans occurs may cause symptoms of lower respiratory fluconazole orally daily. worldwide, frequently in association with tract infection or may be asymptomatic. Control of contacts pigeon or other bird droppings. Skin, bone and other organs are less No action required. C. neoformans var. gattii occurs in frequently infected. endemic foci in the tropics and sub- Control of environment Method of diagnosis tropics where certain eucalypts provide Large accumulations of bird droppings Encapsulated budding forms of the an ecological niche. should be removed after first being fungus may be seen in the CSF, urine or wetted or chemically disinfected to pus using Indian ink staining. Mode of transmission reduce aerosolisation. Cryptococcal antigens may also be Transmission is presumed to be by detected in the CSF and serum. inhalation. Outbreak measures Case clusters are rare. Environmental The diagnosis is confirmed by culture Period of communicability investigations focus on potential (CSF, blood, sputum or andurine) or by Not spread directly from person to reservoirs of infection such as bird histopathology (Mayer’s mucicarmine person, nor spread between animals and droppings, although a definitive source is staining). people. rarely found. Pulmonary cryptococcosis in non-HIV Special settings infected persons usually manifests as a Susceptibility and resistance Where nosocomial transmission is nodule which must be distinguished from Human resistance is presumed to be suspected in single cases or clusters, the a malignancy. Malignancies may co-exist. considerable given the widespread distribution of the organism and the risk of further infections should be Incubation period rarity of infection. It is not known reduced through appropriate control of The incubation period is unknown. whether infection confers immunity. the external environment, with Pulmonary infection may precede investigation of the internal environment Susceptibility is increased during infection in other sites by months or within facilities as appropriate. corticosteroid therapy, immune years. deficiency disorders (especially AIDS), 40 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 41

Cryptosporidiosis

Victorian statutory requirement Oocysts may be identified by microscopy Mode of transmission Cryptosporidial infection (Group B of faecal smears treated with a modified Transmission occurs by the faecal-oral disease) must be notified in writing acid-fast stain. A monoclonal antibody route (person to person and animal to within five days of diagnosis. test is useful for detecting oocysts in person), and via ingestion of faecal and environmental samples. School exclusion: exclude cases from contaminated foods and water. Oocyst excretion is most intense during child care and school until diarrhoea has Period of communicability ceased or until a medical certificate of the first days of illness. Oocysts are Cases may be infectious for as long as recovery is produced. rarely recovered from solid faeces. oocysts are excreted in the stool. Notification is required if Cryptosporidium ELISA assays have been developed for Asymptomatic excretion may persist for spp are isolated from water supplies. the detection of antibodies but these are several weeks after symptoms resolve. not in routine use. Infectious agent Under suitable conditions oocysts may Cryptosporidium parvum is a coccidian Incubation period survive in soil and be infective for up to protozoon. The incubation period is estimated to be six months. one to twelve days, with an average of Susceptibility and resistance Identification seven days. Clinical features Everyone is susceptible to infection. Cryptosporidiosis is a parasitic infection Public health significance People with normal immune systems that commonly presents as and occurrence usually have asymptomatic or self-limited gastroenteritis. Enteric symptoms usually Cryptosporidiosis occurs worldwide. gastrointestinal disease. include watery diarrhoea associated with Young children, the families of infected People with impaired immunity may cramping abdominal pain, bloating, persons, men who have sex with men, experience prolonged illness. vomiting and fever. The disease is usually travelers, health care workers and people mild and self-limiting. In persons with in close contact with farm animals Control measures impaired immunity, particularly those comprise most reported cases. Preventive measures with AIDS, it may be prolonged and life- Substantial outbreaks linked to public Encourage good personal hygiene, threatening. Cryptosporidiosis infection water supplies have been reported in the particularly following contact with may less commonly involve the lungs United States. Multiple outbreaks animals or infected persons. Particular (bronchitis or pneumonia), gall bladder associated with public swimming pools attention to hand washing is required (cholecystitis) or pancreas (pancreatitis). and spas have been reported in Australia during calving seasons on cattle Symptoms usually last four to twenty-one and worldwide. The risk of infection for properties. days. Melbourne residents has been greater for Filter or contaminated drinking water, people exposed to public swimming Method of diagnosis as chemical disinfectants such as pools and household contacts of infected As tests for Cryptosporidium are not chlorine are not effective against oocysts persons. routinely conducted in some facilities at the concentrations used in water treatment. laboratories should be informed if Reservoir cryptosporidiosis is suspected. Reservoirs include humans, cattle and other domestic animals. 42 The blue book: Guidelines for the control of infectious diseases

Control of case Outbreak measures Treatment is symptomatic and An outbreak investigation is required if particularly involves rehydration. two or more cases are clustered in a Antibiotics are not indicated. geographic area or institution. Investigate Exclude symptomatic persons from food potential common sources such as handling, direct care of hospitalised and contact with farm animals, consumption institutionalised patients and care of of contaminated water or unpasteurised children in child care centres until milk or exposure to a common asymptomatic. recreational swimming area. Disinfect soiled articles. The Department of Human Services considers cases may be linked to a As oocyst excretion may persist for public swimming facility if two or more extended periods it is not advisable for people with Cryptosporidium infection adults to swim in public pools for a (confirmed by a pathology laboratory) period of seven days and children for a have used the same pool within two period of four weeks after their diarrhoea weeks of their illness. In this situation has ceased. Showering before swimming pool owners may need to close the is recommended at all times. affected swimming pool until it has been Control of contacts treated and superchlorinated with at The diagnosis should be considered in least 14 mg/L free chlorine for at least 12 symptomatic contacts. hours. Control of environment It is important to ensure that the total Faecal contamination of pools requires chlorine level in a treated pool is less prompt action by the pool operator than 8 mg/L before re-opening it to the including disinfection, but oocysts resist public. If an outbreak is particularly large, standard chlorination. Refer to the the Department may request additional Department of Human Services’ Pool steps to be undertaken. operators’ handbook. Additional sources of information • Victorian Department of Human Services 2000, Pool operators’ handbook, http://www.health.vic. gov.au/environment The blue book: Guidelines for the control of infectious diseases 43

Cytomegalovirus infection

Victorian statutory requirement When infected with CMV, most pregnant Method of diagnosis Notification and school exclusion are not women have no symptoms while a very CMV may be detected by virus isolation required. few have a disease resembling or PCR, usually from urine. Virus may also mononucleosis. However, for those be detected in saliva, breast milk, semen Infectious agent women who are infected for the first time and cervical secretions during primary Cytomegalovirus (CMV) also designated during their pregnancy, one in three will and reactivated infection. as Human herpesvirus 5, is a member of pass the CMV infection on to their CMV causes typical ‘cytomegalic’ cells in the subfamily betaherpesvirus of the developing unborn child. tissue culture and characteristic histologic family . Other members of CMV remains the most important cause features in affected tissues. CMV antigens the herpesvirus group include herpes of congenital viral infections in Australia. may be detected using rapid antigen simplex virus types 1 and 2, varicella For infants who are infected by their tests. Serology is also available where zoster virus (which causes chickenpox), mothers before birth, two potential recent infection is suggested by the and Epstein-Barr virus (which causes problems exist: identification of CMV IgM or a fourfold or infectious mononucleosis/glandular greater rise in serum IgG titres to CMV fever). These viruses share a Generalised infection may occur with from paired sera. characteristic ability to remain dormant symptoms ranging from moderate within the body over a long period. enlargement of the liver and spleen with Isolation of CMV from culture does not , to a fatal illness. With necessarily imply recent infection as Identification supportive treatment most infants with CMV may be excreted for months to Clinical features CMV disease survive. However 80% to years following infection. Positive results Primary CMV infection of children and 90% will have complications within the for CMV from laboratory investigations adults may cause a mononucleosis first few years of life that may include should always be considered with clinical syndrome clinically indistinguishable hearing loss, vision impairment and findings. from that caused by the Epstein-Barr varying degrees of mental retardation. virus (glandular fever). Features include Incubation period Another 5% to 10% of infants who are fever, lymphadenopathy and mild The incubation period of sporadic cases infected but without symptoms at birth hepatitis. More rare features include of CMV usually cannot be determined. will subsequently have varying degrees of anaemia, thrombocytopaenia, Perinatal infection develops three to hearing and mental or coordination pneumonitis, meningoencephalitis and twelve weeks after delivery. In adults, problems. Guillain-Barrè syndrome. Many infections illness usually occurs three to eight are asymptomatic, particularly those in Immunosuppression weeks after blood transfusion and young children. Other people at increased risk of severe between four weeks and four months infection include patients with impaired after organ transplantation. Pregnancy immunity due to HIV/AIDS infection, Healthy pregnant women are not at corticosteroid therapy, lymphoma or Public health significance special risk for disease from CMV sarcoidosis. In these people, disease is and occurrence infection but between 1% and 5% are usually due to reactivation of previous Although infection with CMV is very infected for the first time during their infection. Manifestations include sight- common around the world, symptomatic pregnancy. Many women will already threatening retinitis, pneumonitis, disease is rare. The risk of severe or have been exposed to CMV and so are gastrointestinal ulceration and complicated CMV infection is increased not at risk of a new infection during their inflammation, and neurological disease in some groups including: pregnancy. particularly affecting the brain and spinal cord. 44 The blue book: Guidelines for the control of infectious diseases

• the developing infant during pregnancy CMV is not readily spread by casual Women of childbearing age working in • people with immunosuppression such contact but requires prolonged, intimate hospitals (especially obstetric and as organ transplant recipients, people exposure for transmission. This can occur paediatric wards), child care centres and infected with human immunodeficiency in settings such as child care centres preschools should practice strict virus (HIV) and those being treated for where toddlers shed the virus in saliva infection control precautions and regard cancer. and urine and thereby spread the all body fluids as potentially infectious. infection among them. Serosurveys of adult populations The CMV status of blood and organ worldwide have shown wide-spread Period of communicability donors should be matched to that of recipients wherever possible. If CMV evidence of previous CMV infection with CMV may be shed in the bodily fluids of seropositive donors must be used for seropositivity rates ranging from 40% in any previously infected person, and thus CMV seronegative recipients, highly developed countries to 100% in may be found in urine, saliva, blood, prophylactic use of hyperimmune developing countries. tears, semen and breast milk. The immunoglobulin or antiviral drugs may be shedding of virus may take place The incidence peaks during the perinatal considered. period with a secondary peak among intermittently for months to years after young adults in areas where perinatal primary infection without any detectable Control of case infection is less common. signs, and without causing symptoms. There is no specific treatment recommended for primary CMV infection in particular is of normal hosts. Reservoir associated with prolonged excretion. The Humans. period of excretion seems to be shorter Immunosuppressed persons with CMV retinitis or pneumonitis are usually Mode of transmission in adults. treated in specialist centres with CMV is excreted in urine, saliva, breast Susceptibility and resistance ganciclovir, foscarnet, or milk, cervical secretions and semen Once a person becomes infected, the cidofovir/probenecid. These drugs may during primary and reactivated infections. virus may remain dormant in their body also be of benefit for other complications CMV may be transmitted by: for life (latent infection). Recurrent of CMV infection. • transplacental infection of the foetus disease rarely occurs unless the person’s Control of contacts of a mother with primary or reactivated immune system is suppressed due to None required because of the high infection therapeutic drugs or disease. prevalence of asymptomatic virus • perinatal infection of neonates via Control measures shedders in the community. infective maternal cervical secretions Preventive measures Control of environment or breast milk There is no vaccine available to protect Not applicable. • blood transfusion or organ against CMV infection. transplantation Outbreak measures Public health measures focus on Not applicable. • intimate exposure by mucosal contact reducing the risk of CMV transmission to with infective tissues, secretions or pregnant women, women of childbearing Additional sources of information excretions. age and other people at risk of more • Centers for Disease Control and serious infections. Prevention, Atlanta USA, Cytomegalovirus infection, http://www.cdc.gov/ncidod The blue book: Guidelines for the control of infectious diseases 45

Dengue virus disease

Victorian statutory requirement Identification Laboratory evidence requires one of the Dengue virus infection (Group B disease) Clinical features following: requires notification within five days of Dengue fever (break bone fever) • isolation of dengue virus from clinical diagnosis. Dengue fever classically presents as an material acute febrile illness of sudden onset. It is School exclusion: case should be • detection of dengue viral RNA in extremely debilitating with fever lasting isolated until the fever subsides to clinical material prevent further mosquito bites. three to five days, myalgia (particularly backache), arthralgia, retro-orbital pain, • a significant rise in the level of dengue Infectious agent anorexia, gastrointestinal disturbance, virus specific IgG proven by Dengue virus (DENV) has four related but rash and increased vascular permeability. neutralisation or another specific test distinct serotypes: 1, 2, 3 and 4. There is a high subclinical rate of milder • dengue virus specific IgM in the CSF in Dengue virus has been recognised since disease in children compared to adults the absence of IgM to Murray Valley the latter part of the 18th century as and a low fatality rate. Recovery from encephalitis, Kunjin or Japanese causing epidemics in tropical and infection with one serotype of the encephalitis viruses dengue virus results in homologous subtropical parts throughout the world. • dengue virus specific IgM in serum, immunity but does not provide protection Dengue was first recognised in Townsville except in north Queensland. In north against infection with other serotypes. late in the 19th century and early in the Queensland dengue virus specific IgM 20th century. Outbreaks occurred in an Dengue haemorrhagic fever in serum is acceptable evidence only area from the coast of Western Australia Dengue haemorrhagic fever (DHF) is a when this occurs during a proven to the Northern Territory and down severe complication of dengue virus outbreak. through high rainfall areas of Queensland infection. It occurs mainly in children and Confirmation of laboratory results by a and New South Wales. At that time is characterised by abrupt onset of fever, second arbovirus reference laboratory is Aedes aegypti mosquitoes were widely haemorrhagic phenomena and required if the case occurs in previously distributed in northern Australia and thrombocytopaenia. In its severest form unaffected areas of Australia. North occurred as far south as the Victorian it may result in shock (dengue shock Queensland is currently the only area border in eastern Australia and south of syndrome [DSS]), which has a high with the potential for indigenous Perth in Western Australia. By the 1970s fatality rate. The rate of death from DHF (epidemic) dengue fever in Australia. Aedes aegypti were restricted to a small without DSS is usually quoted at 1–5%. area of northern Queensland. Epidemic This is believed to be caused by immune Incubation period dengue returned to north Queensland in enhancement when a person with The incubation period is usually short but 1981–82. Other outbreaks occurred dengue antibodies due to a previous varies from three to fourteen days. there in the 1990s, a time when Aedes infection is subsequently infected by a aegypti mosquitoes were spreading dengue virus of a different serotype. Public health significance westwards from Queensland to the and occurrence Northern Territory border and towards Method of diagnosis Dengue is not an endemic disease in the New South Wales border. Dengue virus infection is diagnosed by a Australia and the outbreaks which have significant rise in antibodies to the occurred have been due to importations dengue virus serotype. of the virus by a viraemic tourist or returning resident. It is important to 46 The blue book: Guidelines for the control of infectious diseases

rapidly diagnose the disease in returning Mode of transmission Control of case residents and tourists to prevent local Dengue is transmitted by the bite of an Isolate the patient and prevent mosquito spread in receptive areas. Spread or infected mosquito, particularly Aedes access until fever subsides. introduction of Aedes aegypti from its aegypti. This was first recognised by Investigate the source of infection. present distribution in Queensland must workers in Queensland early in the 20th Control of contacts be closely monitored. century. Aedes aegypti breeds in fresh Not applicable. Of great concern has been the repeated water and particularly in man made detection of imported Aedes albopictus containers such as old tyres, pot plant Control of environment mosquitoes into various parts of Australia holders, buckets and tree hollows in • Search for and eliminate breeding sites dating from 1975 in Townsville. Since urban areas. Aedes albopictus is a of Aedes aegypti in the urban area. then it has been detected at various mosquito common in South East Asia • Use mosquito repellents, mosquito times and in various carriers on ships, in and Papua New Guinea and can also be nets and other methods of personal machinery and in car tyres in South an important vector. Other Aedes species protection. are involved in the enzootic monkey Australia, Perth and Darwin. In 1998 it • Control Aedes aegypti near airports. was trapped on a wharf in Cairns and cycle. • Prevent importation of new vectors, for similarly at West Melbourne in 2002. Period of communicability example Aedes albopictus. Preventing the introduction and There is no evidence of person to person establishment of Aedes albopictus transmission. Outbreak measures remains a high priority because this Not applicable. mosquito has the potential to spread Susceptibility and resistance widely over Australia including southern Infection with a serotype of dengue virus areas. It can also transmit dengue and does not necessarily confer immunity. other arboviruses. Control measures Reservoir Preventive measures Humans are the only vertebrate hosts of There are effective vaccines available the virus. There is a jungle cycle between against a number of the dengue virus monkeys and mosquitoes, but this plays serotypes. no role in human disease. Dengue fever can be prevented by: • mosquito control measures • personal protection measures such as long sleeves and mosquito repellents • avoidance of mosquito-prone areas. The blue book: Guidelines for the control of infectious diseases 47

Diphtheria

Victorian statutory requirement The characteristic lesion in the throat is Specimens for C. diphtheriae culture Diphtheria (Group A disease) must be an adherent greyish-white membrane should be obtained from the nose and notified immediately by telephone or fax that first occurs on the tonsils, but may throat and from any other suspicious followed by written notification within five spread up onto the palate and involve lesions. Swabs should be obtained from days. the pharynx and result in respiratory the pharyngeal membrane, or a portion obstruction. of the membrane itself could be School exclusion is relevant for cases submitted for culture. and contacts: The onset is insidious with early symptoms of malaise, sore throat, Selective medium is required to culture • Cases should be excluded until a anorexia and low-grade fever. Patients C. diphtheriae so the testing laboratory medical certificate of recovery is with severe pharyngeal disease may should be notified that the disease is received following at least two negative develop neck swelling giving a clinically suspected. All isolates should throat swabs. The first should be 24 characteristic ‘bull neck appearance’. be sent to a public health reference hours or more after finishing a course Systemic absorption of the toxin can laboratory for C. diphtheriae toxin of antibiotics and the second 48 hours result in neuropathy and cardiomyopathy, detection by polymerase chain reaction later. resulting in early death or later (PCR). • Contacts should be excluded until neurological complications. cleared to return by the Department of Incubation period Laryngeal diphtheria can present as a Human Services. The incubation period is two to five days slowly progressive croup which can but occasionally longer. Infectious agent result in death if the airway obstruction is diphtheriae of the not relieved. Public health significance gravis, mitis or intermedius biotypes is an Non-toxigenic strains of C. diphtheriae and occurrence aerobic gram-positive bacillus. Toxin rarely cause local lesions but may cause Diphtheria occurs worldwide and is more production results when the bacteria are infective endocarditis. prevalent in winter months in temperate infected by a bacteriophage containing zones. Illness is now rare in highly Cutaneous diphtheria presents with the diphtheria toxin gene tox. immunised communities. lesions of variable appearance but which Identification may resemble impetigo. An epidemic began in the Russian Federation in 1990 involving all of the Clinical features Non-cutaneous diphtheria has a case countries of the former Soviet Union and Diphtheria is an acute bacterial infection fatality rate of 5–10% with higher rates in Mongolia. The epidemic has declined caused by toxigenic strains of children under five years and adults over after a peak in 1995 but was responsible Corynebacterium diphtheriae. It primarily 40 years of age. for over 140 000 cases and over 4000 affects the tonsils, pharynx, nose and Method of diagnosis deaths. Over 70% of cases were aged 15 larynx. Other mucous membranes, skin, Diagnosis is usually based on years or older. and rarely the vagina or conjunctivae can observation of the classical greyish-white also be involved. The toxin causes local Diphtheria is now a very rare infection in membrane overlying the tonsils or tissue destruction and membrane Australia but may occur in unimmunised pharynx. formation. people who are recent travellers, or their contacts. The last reported case in 48 The blue book: Guidelines for the control of infectious diseases

Victoria occurred in 1991. Importation of Control measures Diphtheria antitoxin should be given if the infection from other affected Preventive measures there is strong clinical suspicion, countries remains a concern in Australia Diphtheria vaccination is part of the immediately after specimens are taken with the potential to affect unimmunised Australian Standard Vaccination and without waiting for laboratory children and adults as well as adults with Schedule. Primary vaccination is confirmation. The dosage will depend on waning immunity post-vaccination. achieved with three doses of a severity which is assessed by the extent diphtheria-toxoid containing vaccine at of the pharyngeal membrane and Reservoir two, four and six months of age. Booster duration of disease. Antitoxin can be Humans are the usual reservoir and doses are currently recommended. They obtained from CSL Limited. Patients carriers are usually asymptomatic. are given as DTPa at four years of age must be tested for hypersensitivity prior to administration. Co-administration of Mode of transmission and as adult/adolescent formulation DTPa at 15 to 17 years of age. Prior to the antitoxin with corticosteroids may be Transmission is droplet spread from the 8th birthday, DTP-containing vaccines recommended for patients with respiratory tract. More rarely should be used. After the eighth birthday, hypersensitivity to antitoxin. transmission can occur from contact smaller doses of toxoid with articles soiled with discharges from Parenteral antibiotic treatment is usually (adult/adolescent formulation DTPa or infected lesions. required initially and can be either DT-containing vaccines) should be given. erythromycin or benzathine penicillin. Period of communicability Refer to the current edition of The These can be substituted for by Transmission may occur as long as Australian immunisation handbook equivalent oral formulations once the virulent bacilli are present in discharges (National Health and Medical Research patient can swallow comfortably. These and lesions. The time is variable but is Council). should be continued to complete a total usually two weeks or less and seldom Adults who have been fully vaccinated in of 14 days of treatment. more than four weeks without antibiotics. the past should receive a booster dose of Natural infection with diphtheria does Appropriate antibiotic therapy promptly adult tetanus-diphtheria vaccine (Td, not guarantee ongoing immunity. The terminates shedding. The rare chronic ‘ADT’) at the age of 50 years unless a patient should begin or complete active carrier may shed organisms for six booster dose has been documented in immunisation with an age-appropriate months or more. the previous ten years. diphtheria toxoid-containing vaccine Susceptibility and resistance For ‘catch-up’ diphtheria immunisation during convalescence. Infants born of immune mothers are schedules for children and adults refer to Use standard precautions with additional relatively immune, but passive immunity the current edition of The Australian respiratory precautions for pharyngeal is usually lost by six months of age. immunisation handbook (National Health diphtheria and standard precautions with and Medical Research Council). Lifelong immunity is usually, but not additional contact precautions for always, acquired after disease or Control of case cutaneous diphtheria, until the case is inapparent infection. The management of cases involves shown to be clear of carriage. diphtheria antitoxin, antibiotic therapy A primary course of toxoid vaccination The disease is usually not highly and infection control. Consult the current provides long lasting but not lifelong contagious after 48 hours of antibiotic version of Therapeutic guidelines: immunity. Vaccinated individuals may therapy. antibiotic (Therapeutic Guidelines become colonised by C. diphtheriae in Limited). Specialist infectious diseases the nasopharynx while still being advice should always be sought on protected from clinical disease. clinical suspicion of a case of diphtheria. The blue book: Guidelines for the control of infectious diseases 49

Control of contacts For close contacts identified as diphtheria Additional sources of information All close contacts of the case including carriers: • Gidding, HF, Burgess, MA, Gilbert, GL all household contacts and other persons • ensure that prophylactic antibiotic 2000, ‘Diphtheria in Australia, recent directly exposed to oral secretions from therapy has been given (as above for trends and future prevention the case, should have swabs taken for close contacts) strategies’, Communicable Diseases culture from their throat and nose. Intelligence, vol. 24, no. 6. • exclude until two negative swabs, the A prophylactic course of seven days of first not less than 24 hours after oral erythromycin or a single dose of finishing the antibiotics and the other procaine penicillin IM is recommended 48 hours later. for close contacts. Such contacts should If either of the repeat cultures is positive also be kept under surveillance for seven then an additional ten day course of days, regardless of their immunisation erythromycin or penicillin is status. recommended, followed by two repeat Contacts are excluded from childcare cultures. and school until cleared by the Extensive swabbing to detect diphtheria Department of Human Services. Other carriers apart from close contacts is not contacts are advised to exclude recommended. themselves from work and particularly food handling, until bacteriologic Outbreak measures examination shows they are not carriers Outbreaks of diphtheria require of the organism. immunising the largest possible Unvaccinated contacts should be proportion of the population involved, commenced on their primary course of emphasising the need for protection of vaccine. infants and preschool children. In Vaccinated contacts should be given a outbreaks amongst adults immunise booster injection of vaccine if more than groups that are most affected and at high five years have elapsed since their last risk. Repeat immunisations may be dose. recommended after one month. Outbreak investigations involve enhanced case surveillance with laboratory confirmation of all suspected cases, as well as the identification and appropriate management of close contacts and asymptomatic carriers (see Control of contacts, above). 50 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 51

Donovanosis

Victorian statutory requirement Method of diagnosis Control of case Donovanosis (Group C disease) requires The diagnosis is confirmed by First-line treatment for donovanosis is written notification within five days of the demonstrating ‘Donovan bodies’ in azithromycin. Treatment should be initial diagnosis. Wright or Giemsa-stained smears of directly observed. Follow-up is important granulation tissue or by histological as resolution may be slow and Specific information must be notified examination of biopsy specimens. recurrence may occur. under the Health (Infectious Diseases) Regulations 2001. To maintain Incubation period Control of contacts Sexual contacts should be examined for confidentiality, only the name code (first The incubation period is weeks to possible infection. The likelihood of two letters of the surname followed by months. the first two letters of the first name) is transmission per act of unprotected required. Public health significance intercourse is considered to be low and the likelihood of a long term partner Medical practitioners have a statutory and occurrence being infected is low to moderate. obligation under the Children and Young Donovanosis is rare in industrialised Contacts dating back weeks or months Person’s Act 1989 to notify the countries but endemic in some tropical should be traced according to the sexual Department of Human Services Child and subtropical countries and areas history. Protection Service if they believe that a including northern Australia. child is in need of protection on the basis There have been no cases of Control of environment of sexual abuse. donovanosis notified in Victoria since at Not applicable. least 1992. Infectious agent Outbreak measures Previously known as Reservoir Not applicable. Calymmatobacterium granulomatis,a Humans. gram-negative bacillus, the causative Additional sources of information agents is now named Klebsiella Mode of transmission • Australian Government Department of granulomatis. Transmission is primarily sexual. It is Health and Family Services 1998, possible that some cases are transmitted Contact tracing manual – a practical Identification non-sexually. handbook for health care providers Clinical features managing people with HIV, viral Donovanosis is a chronic, progressively Period of communicability hepatitis, other STDs and HIV-related destructive infection which affects the The period of communicability is tuberculosis. unknown but may be months to years. skin and mucous membranes of the • Carter, JS, Bowden, FJ, Bastian, I, external genitalia, inguinal and anal Susceptibility and resistance Myers, GM, Sriprakash, KS, Kemp, DJ regions. Disseminated disease is Everyone is susceptible to infection. 1999, ‘Phylogenetic evidence for uncommon but may be life threatening reclassification of Calymmatobacterium and so should be considered in patients Control measures granulomatis as Klebsiella from endemic areas. It presents initially Preventive measures granulomatis’, International Journal of as raised, ‘beefy’ nodules or sores. Preventative measures include education Systemic Bacteriology, vol. 49, pp. Lesions may extend peripherally with about safe sex practices including use of 1695–700. characteristic rolled edges. Local spread condoms and early detection of infection • Venereology Society of Victoria 2002, to pelvic and abdominal structures by testing of people at risk. National management guidelines for occurs and dissemination to distant sites sexually transmissible infections, can also occur. Venereology Society of Victoria, http://www.msch.org.au 52 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 53

Erythema infectiosum (human parvovirus infection or slapped cheek disease)

Victorian statutory requirement Method of diagnosis Period of communicability Notification and school exclusion are not Diagnosis can be suspected on clinical Children with erythema infectiosum are required. grounds, particularly during outbreaks. most infectious before the onset of the However, confirmation depends on rash and are probably not infectious after Infectious agent demonstrating the presence of specific the rash appears. The causative agent is human parvovirus IgM antibodies or seroconversion to Patients with an aplastic crisis are B19. specific IgG antibodies. Comparison of infectious for a week after the onset of the current antibody status against pre- Identification symptoms. natal screening serology for parvovirus is Clinical features often useful in pregnancy. Immunosuppressed persons with chronic Asymptomatic infection with human anaemia due to infection may excrete Specific IgM antibody titres decline two parvovirus B19 is common. virus for years. to three months after infection while IgG In children it causes a mild illness with levels, which appear two weeks after Susceptibility and resistance little or no fever but a striking redness of infection, can persist indefinitely. Infection generally confers immunity. the cheeks, hence the alternative name Serological surveys suggest 5–15% of of ‘slapped cheek disease’. There may Nucleic acid (PCR) testing and electron preschool children and 50–60% of all also be a lacy pink rash on the trunk and microscopy can also be used to confirm adults are immune. limbs that fades within a week, but which foetal infection. may recur over several weeks on Incubation period Control measures exposure to heat or sunlight. Headache, The incubation period varies from four to Preventive measures itch or common cold-type symptoms twenty days. There is no vaccine available. may also occur. In adults the rash is All people who are non-immune to often absent or atypical. They may have Public health significance parvovirus, immunosuppressed, have cold-type symptoms and sometimes and occurrence chronic haemolytic disorders, or who are painful or swollen joints lasting two or Human parvovirus infection occurs pregnant are at increased risk of three days. worldwide and is a common childhood complications. Parvovirus affects the development of disease. Outbreaks occur during winter red blood cells. As a result several and spring with epidemics occurring These people should be advised of the groups of people are at increased risk of every three to four years. risk that parvovirus infection may pose to them. They should avoid close contact developing complications: Up to 50% of susceptible household with children or adults in settings where contacts and 10–60% of child care or • infection in the first half of pregnancy parvovirus infection may occur such as school contacts may be infected during can cause foetal anaemia with hydrops schools, child care centres and health outbreaks. foetalis. Foetal death occurs in less care facilities. than ten per cent of these cases Reservoir Strict hand washing and separate eating • persons with haemolytic anaemia may Humans. utensils are also advised for these develop transient aplastic crises, often people. in the absence of a rash Mode of transmission • immunosuppressed persons may The virus is transmitted by contact with develop severe chronic anaemia. infected respiratory secretions. It may be spread vertically from mother to foetus and rarely by transfusion of blood products. 54 The blue book: Guidelines for the control of infectious diseases

Control of case There is no specific treatment required for uncomplicated infection. Specialist advice should be sought if a patient with immunodeficiency or a blood disorder contracts parvovirus infection. Control of contacts Intrauterine infection may rarely result in foetal hydrops or death if infection occurs within the first 20 weeks of pregnancy. Medical advice should be sought for pregnant women who have been in close contact with a case of parvovirus infection. Specific antibody testing should be performed to determine the woman’s immune status to parvovirus. Control of environment Not applicable. Special settings Patients and health care workers with acute parvovirus infection should not have contact with high risk hospitalised patients such as pregnant women, the immunosuppressed and those with a chronic haemolytic anaemia.

Outbreak measures General public health measures include: • advising high risk persons of relevant outbreaks • advising patients and contacts to observe strict hand washing after coughing, sneezing and before eating. Slapped cheek infection information sheet for pregnant women Also known as human parvovirus infection or erythema infectiosum

What is slapped cheek infection? How is it spread? How can I protect myself and my Erythema infectiosum is also known as Parvovirus infection is spread by infected baby? ‘slapped cheek disease’ or ‘’ respiratory secretions through coughing, Washing hands before eating or touching and is a common childhood viral sneezing or touching something that has your face can help prevent infection. infection caused by human parvovirus been coughed or sneezed on. About 50% Avoid sharing cutlery, cups and plates. B19. Fifty to sixty percent of women are of non-immune people will become immune to the virus by the time they infected if there is a case in their What action should I take if I reach childbearing age. Occasionally, an household, less if the case is at school or think I have been exposed? unborn baby of a non-immune mother child care. Cases are infectious before A pregnant woman who believes she has can develop problems if infected before the onset of the rash and are probably been in contact with a case of parvovirus the 20th week of pregnancy. not infectious after the rash appears. infection should consult the doctor supervising her pregnancy even if she The incubation period of the infection is What are the symptoms? has no symptoms. Blood testing can 1 to 2 weeks. Most cases experience no symptoms at assist doctors advising women who are all. How can it affect my baby? pregnant of the risk, if any, which In children the infection causes a mild The risk to unborn babies is low. Spread parvovirus infection poses. There is no illness with little or no fever but a striking from mother to baby can only occur if the risk to a woman (or her baby) that already redness of the cheeks (hence ‘slapped mother is not immune. Even if the has immunity. cheek disease’). This may be mother is affected only one-third of If active infection is diagnosed, accompanied by a lacy looking rash that babies will develop the infection ultrasound is performed every 1–2 fades within a week but can re-occur (generally about a month after the weeks to monitor the health of the baby. over several weeks on exposure to heat mother’s illness). If there are signs the baby is having or sunlight. Infection during the first 20 weeks of difficulty with severe a blood Adults often do not have a rash but may pregnancy can rarely cause a form of transfusion while the baby is still in the have cold-type symptoms and/or painful anaemia (low blood count) in the baby. In womb may be considered. or swollen joints over two to three days. many cases this resolves by itself but in Further information some instances it may require treatment. • Your local doctor Very rarely it can be fatal. Parvovirus infection does not cause congenital • Better Health Channel, abnormalities. www.betterhealth.vic.gov.au • Victorian Department of Human Services, 1300 651 160

Department of Human Services www.health.vic.gov.au/ideas Slapped cheek infection information sheet Also known as human parvovirus infection or erythema infectiosum

What is slapped cheek infection? Who is at risk? Can my child attend day care or Erythema infectiosum, also known as Several groups of people are at risk from school? ‘slapped cheek disease’ or ‘fifth disease’ the effects of parvovirus infection on Yes. As cases are infectious before the is a common childhood viral infection developing red blood cells: onset of the rash and are probably not caused by human parvovirus B19. Five to • people with chronic blood disorders infectious after the rash occurs there is 15% of preschool children and 50–60% of (for example, sickle cell disease) may no reason to exclude the child from all adults are immune. develop severe anaemia (low blood school or day care once the rash appears. What are the symptoms? count) Most cases experience no symptoms at • immunosuppressed people (for Further information all. example those on chemotherapy, • Your local doctor organ transplant recipients) may In children the infection causes a mild • Better Health Channel, develop chronic anaemia illness with little or no fever but a striking www.betterhealth.vic.gov.au • occasionally, an unborn baby of a non- redness of the cheeks (hence ‘slapped • Victorian Department of Human immune mother can develop problems cheek disease’). This may be Services, 1300 651 160 accompanied by a lacy looking rash that if infected before the 20th week of fades within a week but can re-occur pregnancy. over several weeks on exposure to heat or sunlight. Adults often do not have a How can I protect myself? rash but may have cold-type symptoms Washing hands before eating or touching and sometimes painful or swollen joints your face can help prevent infection. over two to three days. Avoid sharing cutlery or cups and plates with others. How is it spread? Parvovirus infection is spread by infected What action should I take if I respiratory secretions (coughing, think I have been exposed? sneezing, or touching something that has There is no specific treatment required been coughed or sneezed on). About for uncomplicated infection. Specialist 50% of non-immune people will become advice should be sought if a person with infected if there is a case in their immunodeficiency or a blood disorder household, less if the case is at school or suffers parvovirus infection. A pregnant child care. The incubation period of the woman who believes she has been in infection is one to two weeks. Cases are contact with a case of parvovirus infectious before the onset of the rash infection should consult the doctor and are probably not infectious after the supervising her pregnancy even if she rash appears. has no symptoms.

Department of Human Services www.health.vic.gov.au/ideas The blue book: Guidelines for the control of infectious diseases 57

Food or water-borne illness

Victorian statutory requirement – Clostridium perfringens shellfish poisoning, botulism). Two or more related cases of suspected – Campylobacter spp. Severity depends on host and agent food or water-borne illness must be – E. coli. characteristics and the infectious dose. notified within 24 hours of diagnosis. Hospitalisation and death may occur due – School exclusion: for most to acute dehydration, metabolic acidosis gastrointestinal illnesses children should – Vibrio cholerae/V. parahaemolyticus and subsequent organ failure. be excluded from school or childcare – The duration of illness varies from hours until at least the diarrhoea has ceased. – S.typhi/Paratyphi (24–48 hours in viral and staphylococcal infections) to days and even weeks in Infectious and other causative – Brucella spp. salmonellosis and . agents – Listeria monocytogenes The most frequent causes of food or Method of diagnosis water-borne illnesses are various Diagnostic methods vary according to bacteria, viruses and parasites. Refer to Viruses: the type of infective agent: specific sections for detail on the more • Hepatitis A and E viruses • bacteria can be isolated from faeces or common agents. blood or by detection of toxin • Noroviruses and other small round Non-infective agents: structured viruses (SRSV) • parasites can be isolated by microscopy of fresh or appropriately • heavy metal poisoning, including, • Rotavirus cadmium, copper, lead, tin and zinc preserved faeces • fish toxins that are present in some • viruses can be isolated by stool shellfish or fish like paralytic shellfish Parasites: electron microscopy (EM), immune EM poisoning or ciguatera • Cryptosporidium spp. or paired sera from patients to detect seroconversion to a virus • plant toxins which occur naturally in • Entamoeba histolytica • chemicals can be isolated by some foods such as toxic fungi and • Giardia lamblia green potato skins serological detection of implicated compounds. • toxic cyanobacteria (blue green algae) Identification overgrowth in water. Clinical features Advice regarding specific tests should be Symptoms vary with the causative agent sought from laboratories with expertise and range from slight abdominal pain and in the identification of gastrointestinal Bacteria: nausea to retching, vomiting, abdominal pathogens and chemical agents. • toxin produced in food: cramps, fever and diarrhoea. Fever, chills, headache, malaise and muscular pains Incubation period – Staphylococcus aureus may accompany gastrointestinal Incubation periods are typically short for – Clostridium botulinum symptoms. Vomiting, with or without toxin-producing bacteria and longer for – Bacillus cereus diarrhoea, abdominal cramps and fever others. are common symptoms of viral disease or • damage to gut wall and/or systemic staphylococcal intoxication. Certain food- infection: borne illnesses can present with – Salmonella spp. meningitis or septicaemia (listeriosis) or – Shigella spp. with neurological symptoms (paralytic 58 The blue book: Guidelines for the control of infectious diseases

Public health significance Susceptibility and resistance – protect food from insects, rodents, and occurrence With most infections everyone is and other animals Food and water-borne diseases are susceptible, however sporadic disease is – use pure water thought to be the most common of all more often detected in young children, Incorporation of HACCP (Hazard Analysis acute illnesses. However a large the elderly or immunocompromised Critical Control Point) systems is proportion of disease is not detected, as people. This is in some part due to the important for good manufacturing many people will not seek health care health care seeking behaviours of those practices for food industries. with mild illness. Occurrence is caring for patients in these categories. worldwide and the incidence varies from Vaccines are currently available for country to country. In recent years the Control measures cholera and hepatitis A (refer to relevant detection of outbreaks of viral origin, Preventive measures sections). Prevention of the contamination of especially noroviruses, has been Control of case potable water is very important. increasing. Control of the case ranges from Contaminated water should be treated by supportive treatment and rehydration to Reservoir adequate filtration and disinfection or by hospitalisation. • Soil, dust, cereals boiling. Cases due to infection need exclusion • Bacteria and parasites: fish, birds, Avoiding contamination of food is also from food handling, schools and reptiles, wild and domestic animals important. This can be achieved by: children’s services centres until after the • Viruses: humans • providing raw materials of better diarrhoea has ceased. microbiological quality Mode of transmission Health care workers need exclusion if • educating food handlers about proper Transmission is predominantly via the employed in an area with high risk food processing, preparation, storage faecal-oral route or ingestion of patients, such as special care nurseries and in personal hygiene contaminated food and water sources. or nursing homes, until after the Transmission via aerosols (produced • adopting the following ‘Ten golden diarrhoea has ceased. during profuse vomiting) has been rules for safe food preparation’ Control of contacts implicated in outbreaks involving viral developed by WHO: Control of contacts includes: pathogens. – choose food processed for safety • prevention of further ingestion of Period of communicability – cook food thoroughly contaminated food or water Communicable periods for food and – eat cooked food immediately • surveillance of contacts who are food water-borne illnesses depend on the handlers if required – store cooked food carefully causative agents. Viruses are generally • withdrawal of implicated food (if in – reheat cooked food thoroughly communicable during the acute phase retail outlets) from sale. and up to two days after recovery while – avoid contact between raw foods Control of environment bacteria are generally communicable and cooked foods Investigate water sources or place of during the acute diarrhoeal stage. For – wash hands repeatedly manufacture or preparation of parasites refer to relevant sections in this incriminated food and institute corrective book. – keep all kitchen surfaces meticulously clean action. The blue book: Guidelines for the control of infectious diseases 59

Outbreak measures Food and water-borne outbreaks are usually detected following the onset of illness in a group of people who have shared a common meal. The primary objectives of outbreak control are the rapid identification of the causative agent through epidemiological, environmental and laboratory investigations and prevention of further disease by destruction or denaturation of the source. International measures International outbreaks are increasingly being recognised, primarily due to the increased trade in food and agricultural products worldwide. Food and water- borne pathogens and contaminants have been identified as potential biological terrorism agents. Cases of rare diseases like botulism should be investigated immediately. Some diseases require notification to the World Health Organization, like cholera. Quarantine of suspected sources or halting international trade should be coordinated through Food Standards Australia New Zealand.

Additional sources of information Food Standards Australia New Zealand, http://www.foodstandards.gov.au 60 The blue book: Guidelines for the control of infectious diseases

Common food- or water-borne pathogens

Causative agent Incubation Duration of Predominant symptoms Foods commonly implicated period illness Bacteria 1–10 days 2–5 days Sudden onset of diarrhoea, Raw or undercooked poultry, raw milk, (usually 2–5 days) occasionally >10 days abdominal pain, nausea, vomiting raw or undercooked meat, untreated water E. coli 2–10 days 5–10 days Severe colic, mild to profuse bloody Many raw foods (especially minced enterohaemorrhagic diarrhoea can lead to haemolytic beef), unpasteurised milk, contaminated (STEC, VTEC) uraemic syndrome water E. coli 12–72 hrs 3–14 days Severe colic, watery to profuse Many raw foods, food contaminated by enteropathogenic (enterotoxigenic) diarrhoea, sometimes bloody faecal matter, contaminated water enterotoxigenic enteroinvasive Salmonella serovars 6–72 hrs 3–5 days Abdominal pain, diarrhoea, chills, Raw or undercooked meat and chicken, (non-typhoid) fever, malaise raw or undercooked eggs and egg products Salmonella Typhi/ Typhoid Days-weeks Systemic illness - sustained fever, Raw shellfish, salads, contaminated paratyphi 8–14 days (chronic headache and constipation rather water Paratyphoid asymptomatic than diarrhoea 1–10 days carriers can occur) Shigella spp. 12–96 hrs 4–7 days Malaise, fever, vomiting, diarrhoea Foods contaminated by infected food (blood & mucus) handlers and untreated water contaminated by human faeces Yersinia 3–7 days 1–21 days Acute diarrhoea sometimes bloody, Raw meat especially pork, raw or enterocolitica fever, vomiting undercooked poultry, milk and milk products Vibrio cholerae A few hours to 3–4 days Asymptomatic to profuse painless Raw seafood, contaminated water 5 days watery diarrhoea, dehydration Vibrio 4–30 hours 1–7 days Abdominal pain, diarrhoea, vomiting Raw and lightly cooked fish, shellfish, parahaemolyticus (usually 12–24 hrs) and sometimes fever. Illness of other seafoods moderate severity Listeria 3–70 days Varies Gastrointestinal symptoms rare; Unpasteurised milk, soft cheese, pate, monocytogenes flu-like symptoms to meningitis/ coleslaw, salads, ready to eat seafood, septicaemia; infection in pregnancy cold meats, fresh fruit drinks can result in abortions, neonatal infection Viruses Norovirus (and 24–48 hrs 12–60 hrs Severe vomiting, diarrhoea Oysters, clams, foods contaminated by other viral infected food handlers and untreated gastroenteritis) water contaminated by human faeces Rotaviruses 24–72 hrs Up to 7 days Malaise, headache, fever, vomiting, Foods contaminated by infected food diarrhoea handlers and untreated water contaminated by human faeces Hepatitis A 15–50 days Usually 1–2 weeks Fever, nausea, abdominal Shellfish, foods contaminated by discomfort, possibly jaundice infected food handlers and untreated water contaminated by human faeces The blue book: Guidelines for the control of infectious diseases 61

Common food- or water-borne pathogens continued

Causative agent Incubation Duration of Predominant symptoms Foods commonly implicated period illness Parasites Cryptosporidium 1–12 days 4–21 days Profuse watery diarrhoea, Foods contaminated by infected food abdominal pain handlers and untreated water contaminated by human faeces Giardia lamblia 1–3 weeks 1–2 weeks to months Loose pale greasy stools, Foods contaminated by infected food abdominal pain handlers and untreated water contaminated by human faeces Entamoeba histolytica 2–4 weeks Weeks to months Colic, mucous or bloody diarrhoea Foods contaminated by infected food handlers and untreated water contaminated by human faeces Toxin producing bacteria B. cereus 1–6 hrs (vomiting) < 24 hrs Two known toxins causing nausea Cereals, rice, meat products, soups, (toxin in food) or and vomiting or diarrhoea and vegetables 6–24 hrs cramps (diarrhoea) Clostridium 12–36 hrs Variable (Neurotoxin) Canned food, often home canned food botulinum Blurred or double vision, difficulty (low acid) swallowing, respiratory paralysis, muscle weakness and lethargy C. perfringens 6–24 hrs 24 hrs Sudden onsetcolic, diarrhoea Meats,poultry, stews, gravies, (often (toxin in gut) inadequately reheated or held warm) Staphylococcus 30 min – 8 hrs 24 hrs Acute vomiting, and cramps, may Cold foods (much handled during aureus lead to collapse preparation) milk products, salted meats (toxin in food) Fish / shellfish toxins Scombroid fish Few hours Up to 12 hours Tingling and burning around mouth, Fish such as tuna, mackerel, skipjack, poisoning sweating, diarrhoea, vomiting, bonito, herring and sardines. Fish stored (histamine poisoning) headache, dizziness at >5°C for extended periods Ciguatera poisoning Less than 24 hours Weeks to months Numbness and tingling around Large tropical reef fish mouth, diarrhoea, vomiting and nausea followed by neurological symptoms such as dizziness, blurred vision and temperature reversal. Paralytic shellfish Minutes to Several days Burning and tingling around the Bivalve molluscs poisoning (PSP) several hours mouth and extremities, nausea dizziness, potentially muscle and respiratory paralysis Diarrhetic shellfish 30 mins – 2 hrs Hours to 3 days Diarrhoea, nausea, vomiting and Mussels, scallops and clams poisoning (DSP) abdominal pain 62 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 63

Giardiasis

Victorian statutory requirement Public health significance Control measures Giardiasis (Group B disease) must be and occurrence Preventive measures notified in writing within five days of Occurrence is worldwide and endemic in Preventative measures include: diagnosis. most regions. Over 800 cases are • educating families and personnel of School exclusion: exclude cases from reported in Victoria each year. Infection day care centres in personal hygiene child care and school until diarrhoea has is detected more frequently in children such as the need for hand washing ceased or until a medical certificate of than adults. It is readily transmitted in before meals, after toilet use and recovery is produced. institutions such as day care centres changing nappies among children who are not toilet Infectious agent trained. Other risk factors for infection • protecting public water supplies against faecal contamination Giardia lamblia is a flagellate protozoan include travel to high risk areas, which lives in the duodenum and immunosuppression, male to male sexual • educating travellers about the need for jejunum. intercourse and achlorhydria. safe food and water consumption. Control of case Identification Reservoir Symptomatic cases are usually treated Clinical features Reservoirs include humans and animals with metronidazole or tinidazole. Consult Giardia infection is usually asymptomatic as well as contaminated waters. the current version of Therapeutic but may present as acute or chronic guidelines: antibiotic (Therapeutic diarrhoea associated with abdominal Mode of transmission Guidelines Limited). Treatment of cramps, bloating, nausea, vomiting, fever, Transmission occurs person to person asymptomatic carriers is rarely fatigue and weight loss. Fat and animal to person via hand to mouth warranted. malabsorption may lead to steatorrhoea. transfer of cysts from infected faeces or Symptoms usually last one to two weeks faecally contaminated surfaces. Water- Dispose of faeces in a sanitary and or months. The rate of asymptomatic borne outbreaks may occur due to faecal hygienic manner and disinfect soiled carriage may be high. contamination of public water supplies or clothing and other articles concurrently. recreational swimming areas. Method of diagnosis School exclusion criteria apply until Stool microscopy for cysts or Period of communicability diarrhoea has ceased or until a medical trophozoites can be used for diagnosis of It is communicable for the entire period certificate of recovery is produced. Food Giardia however a negative test does not of cyst excretion. handlers should not attend work until preclude infection. diarrhoea has ceased and strict hygienic Susceptibility and resistance food preparation practices should be Incubation period Everyone is susceptible to infection. maintained. The incubation period is usually one to Relapses may occur. It is also recommended that health care three weeks but it can be longer. It is on workers or child care workers do not average seven to ten days. attend work until diarrhoea has ceased. 64 The blue book: Guidelines for the control of infectious diseases

Control of contacts The diagnosis should be considered in symptomatic contacts. Active case finding among contacts is rarely indicated. Control of environment Disinfection of contaminated areas or water sources is required. Particular attention should be paid to potentially contaminated surfaces in child care centres.

Outbreak measures Two or more related cases may indicate an outbreak and requires prompt reporting to the Department of Human Services. Attempt to identify a potentially common exposure such as child care attendance or exposure to farm animals and recreational swimming areas. Epidemiological, environmental and laboratory investigations may be warranted as per the Department’s Guidelines for the investigation of gastrointestinal illness. The blue book: Guidelines for the control of infectious diseases 65

Gonorrhoea

Victorian statutory requirement In females, an initial urethritis or cervicitis Co-infection with Chlamydia trachomatis Gonorrhoea (Group C disease) must be occurs a few days after exposure. It is sometimes occurs, particularly in notified in writing within five days of frequently mild and passes unnoticed. imported cases. Screening for other diagnosis. Females may have abnormal vaginal sexually transmissible infections such as discharge and post-coital bleeding. Later, chlamydia should be considered when Specific information must be notified pelvic inflammatory disease may testing for N. gonorrhoeae. under the Health (Infectious Diseases) develop. Pelvic inflammatory disease Regulations 2001. To maintain may cause ectopic pregnancy, infertility Incubation period confidentiality, only the name code (first or chronic pelvic pain. The incubation period is usually two to two letters of the surname followed by seven days. the first two letters of the first name) is Conjunctivitis can occur in neonates and required. A questionnaire is sent to the rarely in adults. It may cause blindness if Public health significance diagnosing doctor to collect additional not rapidly and adequately treated. and occurrence information on the case that is essential Septicaemia and septic arthritis are rare Gonorrhoea is common worldwide and for detecting disease trends and complications. affects both sexes. Infection may be informing policy development. symptomatic or asymptomatic. Infections Method of diagnosis of the cervix, anus and throat usually Medical practitioners have a statutory Swabs taken from the urethra, cervix, cause no symptoms. Gonorrhoea can obligation under the Children and Young pharynx, rectum or other site should be have acute and chronic sequelae. Person’s Act 1989 to notify the rolled onto a slide first and then sent to Department of Human Services Child the laboratory in an appropriate Strains of gonococci resistant to Protection Service if they believe that a transport medium. penicillin are common and widespread. child is in need of protection on the basis Resistance to fluoroquinolone antibiotics The following tests can be performed on of sexual abuse. such as ciprofloxacin is common among swabs and smears taken from the site of isolates from infections acquired in Asia. infection: Infectious agent Ciprofloxacin resistance in gonococcal Neisseria gonorrhoeae • Gram stain on discharges smeared on isolates in Victoria is increasing. the slide. Identification Gonorrhoea may increase susceptibility Clinical features • culture on both selective and non- to the sexual acquisition of HIV infection Infections with N. gonorrhoeae may selective media should be used. and increase HIV infectiousness. Culture of N. gonorrhoeae provides present with a number of clinical Other serious complications such as definitive diagnosis, and isolates syndromes. blindness from neonatal conjunctival provide valuable information on The most common presenting symptom infection and the various complications patterns of antibiotic resistance and in males is a painful purulent urethral of pelvic inflammatory disease are other epidemiological markers. discharge. If left untreated, complications currently rare in Victoria. The rate of may include epididymitis, prostatitis and • nucleic acid testing can be performed notified cases of gonorrhoea increased in urethral stricture. Anorectal infection is on cervical and urethral swabs and Victoria in the late 1990s to a level not more common in homosexual males and urine. In women, PCR testing of urine is seen since the mid 1980s. The increase is usually asymptomatic. It may cause less sensitive than PCR testing on involved men who have sex with men pruritis, tenesmus and discharge. endocervical swab specimens. In who comprised approximately two thirds Pharyngeal infection is usually cases diagnosed by PCR, further of cases, and also heterosexual men. A asymptomatic. specimens should be obtained if similar phenomenon was noted possible for culture to allow monitoring elsewhere in Australia and overseas. This of antibiotic resistance. increase has been sustained in Victoria. 66 The blue book: Guidelines for the control of infectious diseases

Reservoir Control of case Additional sources of information Humans. Ceftriaxone plus azithromycin or • Australian Government Department of doxycycline (to cover co-existing Health and Family Services 1997, Mode of transmission chlamydial infection), are used to treat Contact tracing manual – a practical Gonorrhoea is transmitted by contact gonorrhoea. Ciprofloxacin can be used handbook for health care providers with exudates from mucous membranes as an alternative to ceftriaxone when a managing people with HIV, viral of infected people, almost always as the sensitive strain has been identified. hepatitis, other STDs and HIV-related result of sexual activity. Advice on the clinical management of tuberculosis. patients with gonococcal infection can Gonococcal conjunctivitis can occur in • Centers for Disease Control and be found in Therapeutic guidelines: neonates who have had contact with the Prevention 2002, ‘Sexually transmitted antibiotic (Therapeutic Guidelines mother’s infected birth canal during diseases treatment guidelines 2002’, Limited) and the National management childbirth. Morbidity and Mortality Weekly Report, guidelines for sexually transmissible vol. 51 (RR06), pp.1–80, Period of communicability infections (Venereology Society of http://www.cdc.gov/mmwr Communicability may extend for months Victoria, 2002). in untreated individuals. • Crotchfelt, KA, Welsh, LE, DeBonville, Specialist consultation should be sought D, Rosenstraus, M & Quinn, TC 1997, for complicated or disseminated Susceptibility and resistance ‘Detection of Neisseria gonorrhoeae infections and for infection during Everyone is susceptible to infection. and Chlamydia trachomatis in pregnancy. genitourinary specimens form men and Control measures Control of contacts women by a co-amplification PCR Preventive measures Sexual partners of individuals with assay’, Journal of Clinical Microbiology, Preventative measures include education gonorrhoea should be examined and vol. 35, no. 6, pp. 1536–40. about safe sex practices including use of investigated then treated empirically. condoms and early detection of infection • Fleming, DT & Wasserheit, JN 1999, Contact tracing assistance can be by testing of those at risk. ‘From epidemiological synergy to provided by the Department’s partner public health policy and practice: the notification officers (03) 9347 1899. contribution of other sexually Control of environment transmitted diseases to sexual Not applicable. transmission of HIV infection,’ Sexually Transmissible Infections, vol. 73, pp. Outbreak measures 3–17. Not applicable. • Venereology Society of Victoria 2002, National management guidelines for sexually transmissible infections, Venereology Society of Victoria, http://www.msch.org.au The blue book: Guidelines for the control of infectious diseases 67

Haemophilus influenzae infections

Victorian statutory requirement • detection of Hib antigen in CSF when obstruction resembling croup. Other Suspected and confirmed Haemophilus other laboratory parameters are previously rare bacterial causes of influenzae type B (Hib) infections (Group consistent with bacterial meningitis, epiglottitis may now be more likely A disease) must be notified immediately and when there has been no Hib diagnoses. by telephone followed by written vaccination within 21 days of onset. Immunosuppressed individuals of any notification within five days. • Body fluids and urine may give positive age remain at risk from Hib infection. antigen reactions for Hib for up to 21 Asplenic patients are at greater risk of Infectious agent days after vaccination. infection if they have not been Haemophilus influenzae is a gram- appropriately immunised. negative coccobacillus. Invasive Incubation period infections are commonly caused by The incubation period is uncertain. It is Reservoir serotype B. probably two to four days. Humans.

Identification Public health significance Mode of transmission Clinical features and occurrence Hib is transmitted person to person Meningitis Prior to the introduction of Hib vaccine to through respiratory droplet spread and The onset can be sub-acute or sudden the routine immunisation schedule in may also be rarely acquired through with fever, vomiting, lethargy and 1993, Hib disease was the most common contact with infected respiratory meningeal irritation with a bulging serious invasive bacterial infection in discharges. fontanelle in infants and stiff neck and children. At this time at least 500 cases back in older children. of Hib disease annually in Australian in Period of communicability Epiglottitis children less than six years of age. There Hib is communicable for as long as the The patient is usually a child and were 10–15 deaths per year and 20–40% organisms are present in the presents with signs of upper respiratory of survivors were left with permanent nasopharynx. Patients are no longer tract obstruction and a characteristic neurological damage. infectious once they have received 24 to 48 hours of appropriate antibiotic expiratory snore, difficulty in swallowing Indigenous children were at five to six therapy. with drooling of saliva, irritability, times greater risk of developing Hib restlessness and fever. Progression of disease and acquired it at a much Susceptibility and resistance the infection can lead to complete younger age than non-indigenous Sustained immunity is conferred through respiratory obstruction. children. immunisation or prior infection. Maternal H. influenzae type b infection may also By 1998 the number of notified cases in antibody provides passive immunity for a cause other diseases such as Australia had reduced by more than 90%. variable time period after birth. pneumonia, septic arthritis, and The number of notified cases has Infection does not always result in osteomyelitis. continued to fall. Invasive Hib disease is immunity. This is particularly evident in Method of diagnosis now only very rarely seen in Victorian children less than two years of age who Clinical diagnosis is confirmed in the children. There has been no evidence of are unable to mount an antibody response laboratory by: a shift in Hib cases to older age groups. to the type b capsular polysaccharide, • isolation of Hib from a normally sterile Hib epiglottitis may still occur, even following invasive disease. site such as blood or cerebrospinal particularly in adults and unimmunised Most secondary cases among close fluid, typing should be confirmed by an children. This diagnosis should still be contacts occur within the first week after approved reference laboratory considered when a person presents with exposure, though late secondary cases fever and signs of upper respiratory have been reported. 68 The blue book: Guidelines for the control of infectious diseases

Control measures These antibiotics do not clear Hib from In either setting, all persons in the same Preventive measures the nasopharynx. Rifampicin should be household should receive Routine childhood immunisation remains given to cases prior to discharge from chemoprophylaxis and inadequately the most important preventive measure hospital to ensure clearance of the vaccinated children should receive age against Hib disease. Hib vaccine is organism. If the treated patient is less appropriate Hib vaccination. recommended as part of the Australian than two years of age and has not been Child care Standard Vaccination Schedule for all immunised, a course of Hib vaccine If the case attends a child care facility for children at two, four and 12 months of should still be given after discharge from more than 18 hours a week and other age and for older persons with asplenia. hospital. children less than two years of age in this Refer to the current edition of the Respiratory isolation procedures are facility are in close contact, Australian immunisation handbook recommended for 24 hours after the start chemoprophylaxis should be given to all (National Health and Medical Research of treatment. contacts including staff if any of the Council) for further details. Concurrent or terminal disinfection of close contacts are inadequately Before and after splenectomy possibly contaminated items is not vaccinated. Hib is an uncommon cause of post- generally required. Chemoprophylaxis does not eliminate splenectomy sepsis in adults and Control of contacts the need for surveillance and parents of children. Children over two years of age Unvaccinated contacts less than five contacts should be advised of the risk of who are fully immunised do not require a years of age should be immunised as late secondary cases despite Hib booster following splenectomy. A soon as possible. prophylaxis. single dose is recommended for any Chemoprophylaxis other individuals (regardless of age) if Household contacts Decisions about the use and advice incompletely or unvaccinated who have Parents of confirmed cases should be about contra-indications, dosing and close contact with children less than five educated about the risks of secondary supply of rifampicin for chemoprophylaxis years. No booster doses are required. cases in siblings and other close contacts under five years of age, and should always be made in consultation If possible the vaccine should be given at seek early medical review if any close with the Department of Human Services. least two weeks before splenectomy. contacts develop symptoms consistent For adverse effects and contra- Control of case with Hib disease. indications to rifampicin, see section on Intravenous cefotaxime or ceftriaxone meningococcal disease. Chemoprophylaxis (see below) is may be used for empirical therapy until indicated for household contacts only if: Control of environment antibiotic sensitivities are known. See Outbreak measures, below. Consult the current version of • the household of a case contains one Therapeutic guidelines: antibiotic or more infants under seven months of Outbreak measures (Therapeutic Guidelines Limited) and age regardless of vaccination status, or Outbreaks of Hib are now rare. The seek expert infectious disease advice. • the household of a case contains one public health response to a cluster of Hib or more children aged seven months to cases is based on the control principles five years who are not age- outlined above in Control of contacts, appropriately immunised against Hib which may require expansion in the according to the current Australian extent of contact surveillance, Standard Vaccination Schedule. chemoprophylaxis and vaccination. The blue book: Guidelines for the control of infectious diseases 69

Hand, foot and mouth disease

Victorian statutory requirement Public health significance Control of case Notification is not required. and occurrence Control of the case includes: School exclusion is required until all Hand, foot and mouth disease occurs • exclusion from school of children with have dried. worldwide sporadically and in epidemics. hand, foot and mouth disease until all The greatest incidence is in summer and blisters have dried Infectious agent early autumn. Outbreaks occur • covering lesions on hands and feet if group A, mainly type 16, frequently among groups of children in possible and allowing to dry naturally is the infectious agent. child care centres and schools. • avoiding piercing lesions as the fluid Human hand, foot and mouth disease is Reservoir within the blisters is infectious unrelated to the foot and mouth disease Humans. of animals (caused by members of the • good hand washing, cleaning and family Picornaviridae). Mode of transmission disposal of soiled articles. HFMD is transmitted by direct contact Control of contacts Identification with fluid from the vesicular lesions, Not applicable. Clinical features direct contact with nose and throat Hand, foot and mouth disease (HFMD) discharges and faeces of an infected Outbreak measures occurs mainly in children under ten years person, and aerosol droplet spread. Not applicable. of age and in young adults. Symptoms and lesions usually persist for seven to Period of communicability ten days. It is communicable during the acute The clinical picture consists of sore stage of disease from nose and throat throat, fever and vesicular lesions on the secretions and as long as there is fluid in buccal surfaces of the cheeks, gums and the lesions. Viruses persist in the stools sides of the tongue. for several weeks. Papulovesicular lesions of the palms, Susceptibility and resistance fingers and soles commonly occur. Everyone is susceptible to infection. Occasionally maculopapular lesions Immunity to the specific virus may be appear on the buttocks. acquired due to previous infection. Method of diagnosis Second attacks may occur with group A Diagnosis of HFMD is usually clinical. coxsackievirus of a different serotype. Viral isolation from nasopharyngeal or stool specimens is possible but rarely Control measures indicated. Preventive measures Not applicable. Incubation period The incubation period is from three to seven days. Hand, foot and mouth disease information sheet

What is hand food and mouth Signs and symptoms • using separate eating and drinking disease? People usually develop symptoms utensils. Hand foot and mouth disease is caused between three to seven days after being Children with hand, foot and mouth by a virus (usually coxsackie virus A16). infected. disease should be excluded from school It causes blisters on the hands and feet, The most common signs and symptoms and child care centres until all the in the mouth and often in the ‘nappy’ are: blisters have dried. area. • a high temperature (fever) How do you treat hand foot and It is generally only a mild disease that • a sore throat mouth disease? lasts seven to ten days. • small, blister-like lesions that may There is no specific treatment for hand, It is more common during warmer occur on the inside of the mouth, sides foot and mouth disease. weather and tends to spread easily of the tongue, palms of the hands, Use paracetamol (not aspirin) as directed between children. fingers, soles of the feet and ‘nappy’ for fever and any discomfort. This infection is spread by direct contact area. The disease itself is generally mild. If a with fluid from the skin blisters, nose and How long is it infectious? child with hand, foot and mouth disease throat discharges, droplets (sneezing, complains of severe headache, if fever The skin blisters of hand, foot and mouth coughing) and faeces (stools). Good persists, or if there are any other disease are infectious until they become personal hygiene is important to prevent worrying symptoms consult your local crusty and there is no fluid in the blisters. spread of the infection to others. doctor immediately. The virus may also be shed in the faeces There is no connection between this for several weeks after the blisters disease and the foot and mouth disease Further information resolve. that affects cattle and some other • Your local doctor animals. Good personal hygiene is essential to • Better Health Channel, prevent the spread of hand, foot and www.betterhealth.vic.gov.au Who gets hand, foot and mouth mouth disease to others, both for those disease? infected and their carers. This includes: • Victorian Department of Human Services, 1300 651 160 Most people have been infected with the • washing hands carefully after contact virus which causes this disease by the with the blister-like lesions, after time they are adults. So it is generally handling nose and throat discharges, just a small percentage of children who and after contact with faeces such as get features of disease after infection. with nappy changing • allowing blisters to dry naturally. Do not pierce blisters, as the fluid within is infectious

Department of Human Services www.health.vic.gov.au/ideas The blue book: Guidelines for the control of infectious diseases 71

Hendra and Nipah viruses

Victorian statutory requirement Incubation period Malaysia and Singapore. Notification is not required however any The incubation period varies from four No human or animal cases of Hendra or new case of these emerging infections to18 days and rarely up to three months Nipah viral disease have been detected should be discussed with the (Hendra virus). in Victoria. Department of Human Services as a matter of urgency. Public health significance Reservoir and occurrence School exclusion is not required. Fruit bats (Pteropus spp.) are the primary Hendra and Nipah viruses are recently reservoir for both viruses and appear to be Infectious agent recognised zoonotic viral diseases. asymptomatic carriers. Horses are the Two distinct, but closely related RNA Hendra virus appears to have emerged most likely intermediary host in human viruses of the family Paramyxoviridae: from fruit bats in Australia. Horses are infection for Hendra virus although other Hendra virus which has so far only been the intermediary host most commonly species such as cats show serological detected in Queensland, and Nipah virus associated with human infection. The evidence of exposure. first described outbreak of Hendra virus which has been confined to the Malay Pigs are the most likely intermediary host infection occurred in the Brisbane Peninsula. for Nipah virus although seropositive suburb of Hendra in 1994, involving 21 horses and dogs have been identified. Identification horses (14 fatal cases) and two of their Clinical features human handlers (one fatal case). A Mode of transmission Both viral diseases may cause acute smaller outbreak occurred in 1995 The mode of transmission is unknown infection with a variety of symptoms involving two horses and a farmer from although a respiratory route is including fever, headache, shortness of the northern Queensland town of suspected. Human infection has been breath, dizziness, drowsiness and Mackay. most commonly associated with direct confusion. Two of the three recorded The presumed reservoir for Hendra virus is contact with infected horses (Hendra) or cases of Hendra virus in humans were the fruit bat, the Australian flying fox infected pigs (Nipah). Symptomatic fatal. One death was due to septic (Pteropus spp.), which appears to be an infections also occur in cats and other pneumonia while the other was due to asymptomatic host. A 20% seropositive animals. Both viruses have been isolated severe encephalitis. rate to Hendra virus has been found from the urine of infected bats and other In clinical cases of Nipah virus infection among Pteropus bats in Queensland. infected animals. encephalitis is the major manifestation, Wildlife workers who frequently come in to often leading to coma and death in three contact with Australian bats have very low Period of communicability to thirty days. The case fatality rate for seropositive rates. There is no evidence of person to person transmission. clinical cases approaches 50%. The Nipah virus (named after the Baru Sungai frequency of subclinical infections is Nipa village in Malaysia) is closely related Susceptibility and resistance unknown. to Hendra virus. Nipah virus may also Unknown. Method of diagnosis have emerged from fruit bats. Pigs are The diagnosis can be made by the the most common intermediary host Control measures detection of specific neutralising IgM and associated with human infection. The Preventive measures IgG antibodies to either virus. Testing is virus was first identified in 1999 during In an outbreak setting the public should available through the CSIRO Australian the investigation of an outbreak in be advised to avoid contact with possible Animal Health Laboratory at Geelong. several pig-farming provinces on the animal sources, particularly bats. The diagnosis can also be confirmed by Malay Peninsula. The outbreak began in Control of case virus isolation from infected tissues. 1998 and resulted in 265 confirmed Treatment is primarily supportive as human cases with 105 deaths in there is no proven specific treatment. An 72 The blue book: Guidelines for the control of infectious diseases

uncontrolled trial of the Measures could include: ribavirin has suggested it may reduce the • appropriate protective equipment and mortality in Nipah virus encephalitis. hygiene practices for animal handlers Expert treatment advice should be and investigators on implicated farms sought from an infectious diseases or properties physician. • slaughter of infected horses, pigs, or Control of contacts other animals with burial or No person to person transmission has incineration of carcasses been observed. restriction of movement of horses or pigs Control of environment from infected farms or designated areas. See Outbreak measures, below. International measures Outbreak measures Prohibition of export of animal products A single confirmed case of either of from affected areas. these emerging viral infections would constitute an outbreak. Additional sources of information Case investigation determines the likely • McCormack, JG, Allworth, MA 2002, source of infection through a detailed ‘Emerging viral infections in Australia,’ history of the patient’s work and travel Med J Aust, vol. 177, pp. 45–49. history. • Patterson, DL, Murray, PK, Further cases may be identified through McCormack, JG 2000, ‘Zoonotic active case finding amongst close disease in Australia caused by a novel contacts with similar exposure, as well as member of the Paramyxoviridae’, Clin animal source detection if the infection Infect Dis, vol. 27, pp. 112–8. was acquired in Australia. In the event of a case being linked to exposure in Victoria or elsewhere in Australia, the Department would work closely with relevant animal health authorities and scientists to control possible sources of infection. The blue book: Guidelines for the control of infectious diseases 73

Hepatitis A

Victorian statutory requirement Incubation period Period of communicability Hepatitis A infection (Group B disease) The incubation period is fifteen to fifty Cases are most infectious from the latter must be notified in writing within five days, with an average of 28–30 days. half of the incubation period until a few days of diagnosis. days after the onset of jaundice, Public health significance corresponding to a peak in transaminase School and child care exclusion are and occurrence outlined below (see Control measures). levels in cases without jaundice. Most Hepatitis A occurs worldwide. In cases are not infectious after the first Infectious agent developing countries most people are week of jaundice. Long term carriage or Hepatitis A virus (HAV) is the causative infected during childhood. With good excretion of the virus does not occur. agent. sanitation and hygiene in the developed world, most people now reach adulthood Susceptibility and resistance Identification without experiencing infection. There are All non immune people are susceptible Clinical features about 70–200 cases per year in Victoria. to infection. Immunity after infection is Illness due to hepatitis A typically causes Notifications have been declining probably lifelong. acute fever, malaise, anorexia, nausea nationally since the late 1990s. Infection and abdominal discomfort. This is is more common in travelers to endemic Control measures followed a few days later by dark urine areas, injecting drug users, children in Preventive measures and jaundice. Symptoms usually last childcare and men who have sex with Education about good hygiene is several weeks although convalescence men. important, particularly hand washing before handling food and eating and after may sometimes be prolonged. Severe Common source outbreaks due to using the toilet. Inadequate sanitation illness may rarely occur when hepatitis A contaminated food are rare. infection complicates pre-existing liver and housing may contribute to endemic disease. Infants and young children Reservoir illness. infected with HAV may have a mild Humans. Inactivated hepatitis A vaccines are illness with few or no symptoms, with available for use in persons two years of jaundice often being absent. Mode of transmission age and over. Protection begins within Infection is transmitted by the faecal-oral Method of diagnosis 14–21 days after the first dose. A second route from person to person or via A blood test indicating IgM anti-HAV dose is required for long term protection. fomites. Infectious food handlers may antibodies confirms recent infection. The vaccine is recommended for contaminate non-cooked foods such as These antibodies are present for two to travellers to high risk areas, persons in salads. four months after infection. IgG high risk occupations such as childcare antibodies alone are evidence of past Infection can also occur through workers and emergency services infection. ingestion of contaminated food or water. personnel, injecting drug users and men Filter-feeding shellfish such as oysters who have sex with men. In the acute stage of the illness, blood raised in contaminated waters may biochemistry shows elevated Control of case harbour the virus. transaminase levels indicating Treatment is generally supportive. hepatocellular damage. The pattern of The precise timing and mode of Exclude from childcare, school or work liver function tests may be non-specific transmission are often difficult to define. for at least one week after the onset of in later illness. illness or jaundice and until they are well. 74 The blue book: Guidelines for the control of infectious diseases

Children must have a medical certificate Surveillance of contacts in a household and consideration given to the provision of recovery before returning to school or or workplace should be maintained. of IG prophylaxis for co-workers and child care. Live vaccines such as Measles Mumps patients in their direct care whilst Educate the patient and their family on Rubella (MMR) should not be infectious. Surveillance of contacts in the the need for strict hygiene practices. administered for three months after a health care facility should be maintained. Infected persons should not prepare dose of IG, and may also be ineffective if Control of environment meals for others while infectious, nor given in the 14 days prior to IG. A source of infection should always be share utensils, toothbrushes, towels and Reschedule such routine vaccinations. sought. For apparently sporadic cases, face washers. When the case is a food handler: consider contact with another known case and recent travel to an area where Dispose of or thoroughly wash nappies of • consider serological testing of co- the disease is endemic. Acquisition of infants that have hepatitis A. workers to determine whether they infection from young children, particularly Control of contacts have been infected or are susceptible those in childcare should be considered. Normal immunoglobulin (IG) 0.02 mL/kg • place uninfected susceptible co- Special attention should be given to body weight intramuscularly is workers under surveillance and give toilet hygiene in schools and childcare recommended for: them IG prophylaxis. These persons centres. Ensure that soap and water are • household and sexual contacts of the remain at a risk of developing mild available and are used regularly to wash case illness modified by IG but can generally hands. continue to work provided good • staff and children in close contact with personal hygiene and food handling Food premises, health care facilities or a case in a childcare centre. practices are maintained child care centres where a case has worked whilst potentially infective should IG is not recommended for usual office, • undertake surveillance for hepatitis A school or factory contacts. IG must be be requested to carry out a clean up in in patrons by seeking a history of accordance with the Department’s given within seven to ten days of exposure to the food premises from exposure to be effective. IG is rarely Guidelines for the investigation of cases notified over the next two to gastrointestinal illness. given to persons exposed to a potential three months common source of hepatitis A such as Outbreak measures food or water because cases related to • carefully consider the role of the Clusters of cases possibly related to a such a source are usually recognised too infected food handler. If transmission to single source will require epidemiological long after the exposure for IG to be patrons appears likely, consider urgent and environmental investigation, effective. Timely administration of IG will follow-up of exposed patrons to offer including case finding and surveillance prevent or modify clinical illness for them IG prophylaxis. Note that when and public health measures to prevent approximately six weeks after the dose. the is a patron, it is usually further cases. However, people exposed and infected too late to offer IG prophylaxis to other before the administration of IG may still diners, although personal contacts of Use of the hepatitis A vaccine in an experience a mild infection, and may the patron case should be offered IG outbreak setting is dependent on rapid have the potential to infect others if strict according to the usual protocol. identification of the outbreak and personal hygiene is not maintained. When the case is a health care worker, persons at risk, and the ability to achieve the role of the case should be assessed high vaccine coverage levels. The blue book: Guidelines for the control of infectious diseases 75

Hepatitis B

Victorian statutory requirement Serology for newly acquired infections • detection of HBV DNA and high levels Hepatitis B infection (Group B disease) requires one of the following: of specific IgM to hepatitis B core must be notified in writing within five • detection of HBsAg in a patient shown antigen (IgM HBcAg) in the absence of days of diagnosis. to be negative within the last 24 prior evidence of HBV infection. School exclusion is not applicable. months Serology for chronic carriers requires: • detection of HBsAg and high levels of • detection of HBsAg or HBV DNA in the Infectious agent specific IgM to hepatitis B core antigen serum of a patient on two occasions at Hepatitis B virus (HBV) is the causative (IgM HBcAg) in the absence of prior least six months apart. agent. evidence of HBV infection The following table summarises the Identification interpretation of hepatitis B virus Clinical features serology. Less than 10% of children and only 30–50% of adults with acute HBV Tests Results Interpretation infections will have icteric disease. The HbsAg negative onset is usually insidious with anorexia, anti-HBc negative susceptible – discuss vaccination abdominal discomfort, nausea, vomiting, anti-HBs negative lethargy and occasional rash and HbsAg negative arthralgia. It often progresses to dark anti-HBc positive immune due to infection urine and jaundice. The severity of anti-HBs positive infection ranges from asymptomatic HbsAg negative cases detected only after further anti-HBc negative immune due to hepatitis B vaccination investigation of abnormal liver function anti-HBs positive tests, to fulminating and often fatal case HbsAg positive with extensive acute hepatic necrosis. anti-HBc positive acutely infected IgM anti-HBc positive Method of diagnosis anti-HBs negative HBV infection is confirmed by the HbsAg positive detection of hepatitis B surface antigen anti-HBc positive chronic carrier (HBsAg) or of HBV DNA in serum. IgM anti-HBc negative Serology determines whether infections anti-HBs negative are newly acquired or reflect chronic HbsAg negative carriage. anti-HBc positive * five interpretations possible (see below) anti-HBs negative

Source: Centers for Disease Control and Prevention (CDC). *1. May be recovering from acute HBV infection 2. May be distantly immune and test not sensitive enough to detect very low level of anti-HBs in serum 3. May be susceptible with a false positive anti-HBc 4. May be undetectable level of HbsAg present in the serum and the person is actually a carrier 5. Maternal antibody 76 The blue book: Guidelines for the control of infectious diseases

Incubation period Mode of transmission Susceptibility and resistance The incubation period is 45–180 days Although hepatitis B surface antigen All non immune people are susceptible with an average of 60–90 days. (HBsAg) has been found in virtually all to infection. Immunity conferred through body secretions and excretions, only infection confers lifelong immunity in Public health significance and blood (serum or plasma), semen and those who do not become chronic occurrence vaginal fluids have been shown to be carriers. Hepatitis B virus is a major cause of infectious. chronic hepatitis, cirrhosis and Control measures Transmission occurs via percutaneous hepatocellular carcinoma. Preventive measures and permucosal exposure to Universal vaccination for hepatitis B is An estimated two billion people have contaminated blood and body fluids. This part of the Australian Standard been infected with HBV worldwide, 350 may occur during: million of whom are chronic carriers. Vaccination Schedule. All children are • sexual contact Each year an estimated one million offered a birth dose which should be people die as a result of HBV infections • birth given within the first seven days after birth and thereafter the infant should and over four million new acute clinical • injecting drug use cases occur. receive hepatitis B vaccine at 2, 4 and 12 • some household activities such as months of age. In countries with low endemicity (HBsAg sharing razors or toothbrushes prevalence less than 2%) most infections For those not immunised in childhood, • invasive procedures in the community occur in young adults and especially the ASVS recommends all pre- such as tattooing or body-piercing, if among persons who belong to known adolescent children aged 10–13 years there has been inadequate infection high risk groups. Risk of HBV infection receive hepatitis B vaccine. This is control increases with: carried out in Year 7 of school. These • invasive medical or dental procedures children receive two doses of adult • unprotected sexual contact if there has been inadequate infection formulation hepatitis B vaccine. • injecting drug use control. Health care workers should ascertain • household and sexual contact with All blood and blood products produced their HBV immune status, particularly known HBV infected persons for medical purposes in Australia are those engaging in invasive procedures. If • incarceration carefully screened for HBV and other infected, health care workers should blood-borne viruses using nucleic acid consult with a medical practitioner to • workplace exposure to blood. testing. review and consider modifications to In higher endemicity areas (HBsAg their work practices to reduce the risk of prevalence 2%) most infections occur as Period of communicability transmission to others in accordance a result of perinatal transmission from The blood of infected persons is infective with the guidelines of their relevant HBsAg-positive mothers or early many weeks before the onset of professional registration boards. Non- horizontal transmission via close contact symptoms and remains infective through immune health care workers should be in the household family setting. the acute clinical course of the disease vaccinated against HBV. and during the chronic carrier state, Reservoir which may persist for life. The proportion Humans. of infected individuals who become carriers is inversely related to their age at infection. Persons who are HBV DNA positive are highly infectious. The blue book: Guidelines for the control of infectious diseases 77

Control of case Control of environment All newly acquired cases should be Appendix 5 outlines procedures for interviewed to identify likely risk factors dealing with spills of blood and body for their infection and to identify others fluids. who may be at risk of infection. If the patient’s history suggests nosocomial Outbreak measures transmission such as a surgical Special settings procedure, or other possible source of Health care workers infection that may put the general public Registration boards should be consulted at risk such as a commercial tattoo, the in relation to their policies regarding Department of Human Services should health care workers with blood-borne be contacted for further advice and viruses. For example, the Medical investigation. Practitioners Board of Victoria has a policy on medical practitioners and Isolation of HBV positive patients is not medical students who carry a blood- required. The infected person should be borne virus which is available at educated about transmission routes, safe http://medicalboardvic.org.au. injecting and sexual practises, blood and Recommendations are also included in body fluid precautions, and not donating Infection control guidelines for the organs or blood. prevention of transmission of infectious Control of contacts diseases in the health care setting, Non-immune sexual contacts should be http://www.icg.health.gov.au offered hepatitis B immunoglobulin (HBIG) 400 IU IM within 14 days of contact and commence hepatitis B vaccination. Household contacts should be tested for HBsAg and anti-HBc and offered vaccination if susceptible. Infants born to HBsAg positive mothers should be given a single dose of HBIG and vaccine within 12 hours of birth, at different sites. The remaining doses of vaccine should be given at 2, 4 and 12 months of age. Recipients of needle-stick injuries should be considered for hepatitis B immunoglobulin (see Appendix 4). 78 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 79

Hepatitis C

Victorian statutory requirement Method of diagnosis Public health significance Hepatitis C infection (Group B disease) HCV infection is confirmed by using the and occurrence must be notified in writing within five combination of a HCV antibody test and Hepatitis C occurs worldwide. Current days of diagnosis. PCR to detect HCV RNA. A positive estimates suggest that more than 200 antibody test implies previous infection Specific information is required to be 000 Australians have been infected with by the virus and a positive HCV RNA notified under the Health (Infectious this virus and that 11 000 new infections implies ongoing infection. Diseases) Regulations 2001. In certain are occurring each year. Specific groups circumstances the attending doctor and Antibodies are directed against the such as injecting drug users are at patient may be asked to complete a products of expressed clones or peptides greater risk of HCV infection. questionnaire to collect additional of the HCV. First generation enzyme Three quarters of people infected with information. All information collected by immunoassay (EIA) for antibody HCV become chronic carriers of the the Department of Human Services is detection became available in Australia virus. Of those chronically infected, treated as confidential. It is used for in 1990 and since then second and third approximately 10–20% will develop liver reasons such as detecting disease generation EIA tests with improved cirrhosis over a period of 15–40 years trends and to inform public health action sensitivity and specificity have been and an estimated 5% will develop and policy development. developed. hepatocellular carcinoma after 40 years School exclusion is not required. Supplemental tests are also available in of infection. the form of recombinant immunoblot There are at least six major genotypes of Infectious agent assays (RIBA). The significance of HCV. At present the main genotypes Hepatitis C virus (HCV) is a small RNA equivocal reactivity detected by EIA tests found in the Australian population are 1 virus that is closely related to the and indeterminate reactivity detected by (54%), 3 (36%) and 2 (6%). flaviviruses and animal pestiviruses. RIBA testing remains problematic in low risk groups. Reservoir Identification Humans. Clinical features A positive HCV RNA test is a marker for Most infections with HCV are viraemia and ongoing infection. A single Mode of transmission asymptomatic and acute infection may negative PCR does not exclude infection Hepatitis C is primarily transmitted by only be detected in patients by the as viraemia may be intermittent. The blood-to-blood contact. patient should be retested in six to 12 development of elevated serum alanine In Australia and other Western countries months time. aminotransferase (ALT) levels. When the sharing of injecting equipment by symptoms and signs do occur, they are Current EIA tests cannot distinguish intravenous drug users is the most similar to other forms of viral hepatitis between patients who are currently common mode of transmission. but usually milder. Estimates vary but infectious and those who have recovered Tattooing, ear piercing and body piercing between 10% and 50% of people infected from infection and developed immunity. using unsterile equipment are other with HCV completely recover and are potential sources. There is a high Incubation period clear of the virus in the subsequent few prevalence of HCV in people who have The incubation period ranges from two years. Community based studies report a been in prison because of the high weeks to six months. It is most greater likelihood of viral clearance likelihood of injecting drug use and commonly six to nine weeks after which compared with hospital-based studies. If tattooing. symptoms of ongoing disease occur they serum ALT levels rise. Current HCV may be non-specific and include fatigue, antibody tests become positive two to headaches and nausea. three months after exposure. 80 The blue book: Guidelines for the control of infectious diseases

Health care and laboratory staff who Period of communicability genotype and sometimes whether handle blood and blood products are at Communicability occurs during the acute previous treatment has failed. Combined increased risk. The Centers for Disease clinical stage of HCV infection and therapy with alpha interferon and Control and Prevention report that the indefinitely in the chronic carrier stage. ribavirin or pegylated interferon and risk of contracting hepatitis C after All HCV positive individuals should be ribavirin are possible treatment percutaneous exposure such as needle considered potentially infectious regimens. stick or sharps injury from the blood of a although the risk is minimal in the non- Counselling of the patient is a very person with hepatitis C antibody has viraemic (PCR negative) individual. important part of the management. This been estimated at 0–7% (average 1.8%). counselling should include: The risk of transmission is negligible if Susceptibility and resistance the source is HCV RNA-negative. All non immune people are susceptible • exploring the likely source of the to infection. The degree of immunity infection Sexual transmission rates of HCV following infection is uncertain. If infection are very low. The risk is • current knowledge of the natural infection resolves and the virus is increased if the HCV positive partner is history cleared, the person can be re-infected immunocompromised as the viral blood • possible symptoms with the same and other genotypes. titre may be increased, or when there is However there is some evidence from • advice on prevention of further the possibility of blood-to-blood contact cohort studies that the likelihood of transmission of infection for example sex during menstruation and reinfection is reduced after the first HCV • lifestyle issues such as immunisation traumatic sexual practices. infection. against hepatitis A and B, minimisation Mother to baby transmission is of alcohol intake, cessation of smoking approximately 5–6% and is thought to Control measures and healthy diet. occur only when the mother is HCV RNA Preventive measures The patient should be advised not to: positive. The likelihood of transmission is All health care providers with potential increased if the mother is also infected contact with blood or body fluids should • donate blood or body organs with HIV. Although HCV has occasionally use standard precautions. • share injecting equipment been detected in breast milk there is no Use single-use equipment for all skin • share personal items such as evidence that HCV is transmitted from penetration procedures or use toothbrushes or razors. mother to child by breast feeding. appropriate cleaning, disinfection or They should also be advised to: Community or household transmission of sterilisation methods when reusable HCV is considered rare. instruments are used for any procedure. • consider discussing their condition This includes needles. with their health care provider when A proportion of HCV positive individuals undergoing any dental or medical do not fall into any known risk subgroup. Control of case procedure They may have forgotten that they had All people diagnosed with HCV infection exposure to injecting drugs many years should be reviewed by a hepatitis • wipe up any blood spills with single ago or they may be unwilling to discuss specialist (either a gastroenterologist or use disposable paper towels and clean the possibility. an infectious diseases physician) and an area with detergent and warm water assessment made of the likelihood of Re-use of poorly cleaned needles by • cover any cuts or wounds with an disease progression. Treatment is offered medical practitioners and others in some occlusive waterproof dressing based on the presence of liver fibrosis. countries and cultural practices that • place blood-stained paper tissues, involve skin piercing are other potential Length of treatment and type of sanitary towels or dressings in a plastic sources of infection. treatment depends mainly on the bag before disposal The blue book: Guidelines for the control of infectious diseases 81

• use safer sex practices. People in long Other settings • Dore, G, Grulich, A, Kidd, M, Hoy, J term stable relationships will need to All workplaces should have policies and McCoy, R, Mijch, A & Strasser, S 2001, discuss condom use with their health procedures in place regarding action to HIV/Viral hepatitis – a guide for primary care provider. Safe sex is not routinely be taken in the event of a blood spill or care, Australasian Society for HIV recommended among long term sharps injury. Further information can be Medicine, http://www.ashm.org.au monogamous couples. found in Infection control guidelines for • Mehta, SH, Cox, A, Hoover, DR, Wang, Control of contacts the prevention of transmission of XH, Mao, Q, Ray, S, et al. 2002, There is no vaccine available for the infectious diseases in the health care ‘Protection against persistence of prevention of hepatitis C. http://www.icg.health.gov.au/ hepatitis C’, Lancet, vol. 359, no. 9316, Prophylactic immunoglobulin for contacts Additional sources of information pp. 1478–1483. has no role. • Centers for Disease Control 1997, • Victorian Department of Human Control of environment ‘Notice to readers – Services 2002, Hepatitis C Strategy Not applicable. Recommendations for follow-up of 2002–2004, health-care workers after occupational http://www.health.vic.gov.au/ideas Special settings exposure to hepatitis C’, Morbidity and Health care workers Mortality Weekly Report, vol. 46, no. 26, Registration boards should be consulted pp. 603–606. in relation to their policies regarding health care workers with blood-borne • Centers for Disease Control 2001, viruses. For example, the Medical ‘Updated US public health service Practitioners Board of Victoria has a guidelines for the management of policy on medical practitioners and occupational exposures to HBV, HCV medical students who carry a blood- and HIV and recommendations for borne virus which is available at postexposure prophylaxis, Morbidity http://medicalboardvic.org.au. and Mortality Weekly, vol. 50, RR –11, Recommendations are also included in pp. 1–42. Infection control guidelines for the • Charles, PG, Angus, PW, Sasadeusz, JJ prevention of transmission of infectious & Grayson, LM 2003, ‘Management of diseases in the health care setting, healthcare workers after occupational http://www.icg.health.gov.au exposure to hepatitis C’, Medical Antenatal care Journal of Australia, vol. 179, no. 3, pp. Antenatal care should include a 153–157. comprehensive assessment of hepatitis • Crofts, N, Dore, G & Locarnini, S (eds.) C risk factors. Women found to be at 2001, Hepatitis C – An Australian higher risk of hepatitis C infection or perspective, IP Communications. exposure should be encouraged to undergo hepatitis C antibody screening. 82 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 83

Hepatitis D (delta hepatitis)

Victorian statutory requirement Incubation period Period of communicability Hepatitis D infection (Group B disease) Approximately two to eight weeks. This is similar to that of HBV. Persons must be notified in writing within five infected with the HDV are thought to be days of diagnosis. Public health significance most infectious before the onset of and occurrence School exclusion is not applicable. symptoms. All persons with Hepatitis D occurs worldwide and is asymptomatic infection, persons with Infectious agent most prevalent in countries that have a acute disease and those with chronic Hepatitis D virus (HDV) is a virus-like high incidence of hepatitis B. The highest carriage of the virus are infectious to particle consisting of a coat of hepatitis incidence occurs in parts of Russia, others. B virus (HBV) surface antigen and a Romania, southern Italy, Africa, pockets unique internal antigen, the delta of South America and the islands of the Susceptibility and resistance antigen. Western Pacific. All people susceptible to hepatitis B Despite high rates of hepatitis B in Asian infection or those who have chronic Identification countries the incidence of hepatitis D is hepatitis B can be infected with HDV. Clinical features lower. Hepatitis D is uncommon in Control measures Onset of disease is usually abrupt, with Australia. Three to twelve cases are Preventive measures signs and symptoms resembling those of reported per year in Victoria. hepatitis B infection. It may be severe Prevention of hepatitis B infection with and is always associated with a Reservoir hepatitis B vaccine prevents infection coexistent HBV infection. Co-infection HDV is unable to infect a cell by itself with HDV. For persons with chronic (simultaneous infection with HBV and and requires co-infection with HBV to hepatitis B infections, the only preventive HDV) or superinfection (infection with undergo complete replication. Therefore measure is avoidance of exposure to HDV in a person who already has HBV) humans with HBV infection act as potential sources of HDV. This means with HDV is usually more severe than reservoirs. always using a new needle and syringe HBV infection alone and more likely to when injecting drugs and practising safe result in fulminant disease. Co-infection Mode of transmission sex. has a lower risk of severe chronic disease This virus is transmitted by the same Control of case than does superinfection. methods as HBV: exposure to infected There is no specific treatment for blood and serous body fluids, Method of diagnosis hepatitis D, although alpha-interferon has contaminated needles, syringes or blood Serological diagnosis is made by: been shown to be of some benefit. and plasma product transfusions. Sexual Expert advice for ongoing management • detection of total antibody to HDV transmission may also occur but is less should be sought. (anti-HDV). A positive HDV IgM result common than with hepatitis B. Perinatal Isolation is not required. indicates ongoing replication infection is rare. Infection may occur at • detection of HDV-specific RNA by the same time as a new HBV infection Educate patient about safe injecting, safe polymerase chain reaction (PCR) (co-infection) or after someone has been sex and blood and body fluid testing. PCR is the most sensitive infected with HBV and become a chronic precautions. assay for assessing HDV viraemia. HBV carrier (super-infection). 84 The blue book: Guidelines for the control of infectious diseases

Control of contacts Initiate contact tracing with patient. Susceptible sexual, injecting and household contacts should be offered hepatitis B vaccine. Vaccination against hepatitis B prevents HDV infection. Control of environment Not applicable.

Outbreak measures Not applicable. The blue book: Guidelines for the control of infectious diseases 85

Hepatitis E

Victorian statutory requirement Public health significance Control measures Hepatitis E infection (Group B disease) and occurrence Preventive measures must be notified in writing within five Sporadic cases and epidemics in adults Good personal hygiene is important, days of diagnosis. have occurred in India, areas of the particularly after defecation. Travellers to School exclusion is not applicable. former Soviet Union, some African endemic areas should be advised of the countries, Mexico and parts of Asia. The risk and avoid ingestion of potentially Infectious agent disease is not endemic in Australia and contaminated water. There are no Hepatitis E virus (HEV) is the causative cases reported to date have occurred in vaccines against HEV. agent. travellers, with the exception of one Control of case patient with no history of overseas travel Treatment is supportive only, particularly Identification who was diagnosed in the Northern the maintenance of hydration. Clinical features Territory in 1995. The clinical course of disease due to HEV Food handlers must not work for at least is similar to that of hepatitis A. It is a self- Reservoir seven days after the onset of jaundice and limiting disease of adults aged 15–40 Humans and some primates act as until well. years. A high case fatality rate (up to reservoirs. It is recommended that health care 20%) has been described in pregnant workers and child care workers remain Mode of transmission women affected in their third trimester of away from work for at least seven days Hepatitis E is transmitted via pregnancy. after the onset of illness and until well. contaminated water and possibly through Children should not attend school or child Method of diagnosis person to person transmission via the care for seven days after the onset of Exclusion of other causes of acute faecal-oral route. Evidence of infection in symtoms. hepatitis, particularly hepatitis A is rats and other rodents in some endemic important. HEV may be detected by countries suggests other mechanisms of Control of contacts immune electron microscopy of faeces transmission are likely. Consider the diagnosis in symptomatic collected during the acute phase. contacts. Immunoglobulin prepared from Serological tests to confirm HEV Period of communicability donors in non-endemic countries will not infection are available through the The period of communicability is prevent infection or disease. Victorian Infectious Diseases Reference unknown. HEV has been detected in If the case has worked as a food handler, Laboratory. stools 14 days after the onset of child care worker or health care worker, jaundice. Incubation period surveillance for further cases in the work The incubation period varies from two Susceptibility and resistance place should be carried out. weeks to two months. In different Susceptibility is unknown, however Control of environment epidemics the average incubation period disease tends to occur in adults and Infected persons should be advised to has varied from 26 to 42 days. pregnant women are at particular risk of maintain strict personal hygiene and fulminating disease. avoid preparing meals for others unless adequate food safety can be guaranteed. 86 The blue book: Guidelines for the control of infectious diseases

Food premises, child care centres or Additional sources of information health care facilities where a case has • Heath, TC, Burrow, JN, Currie, BJ, worked whilst potentially infective should Bowden, FJ, Fishe,r DA, Demediuk, BH, be requested to complete a clean up in Locarnini, SA, Anderson, DA 1995, accordance with the Department’s ‘Locally acquired hepatitis E in the Guidelines for the Investigation of Northern Territory of Australia’, Med J gastrointestinal illness. Aust., vol. 162, no. 6, pp. 318–9. Outbreak measures • World Health Organization, A case with no history of overseas travel http://www.who.int/csr would constitute an outbreak in Victoria. Immediate notification is critical to identify the source and prevent further disease. A detailed epidemiological, environmental and laboratory investigation of common exposures, particularly water, amongst cases is necessary. The blue book: Guidelines for the control of infectious diseases 87

Herpes simplex infections

Victorian statutory requirement per cent of primary infections cause a depending on sexual practices. Notification is not required. more severe form of disease manifested HSV 2 infections are rarely associated by fever and malaise. This may last a School exclusion: young children with with aseptic meningitis and radiculitis. week or more and can be associated cold sores who are unable to comply with vesicular lesions leading to ulcers in with good hygiene practices should be Method of diagnosis and around the mouth excluded while the lesion is weeping. The diagnosis may be suggested by (gingivostomatitis), eye infection Lesions should be covered by a dressing cytologic changes in tissue scrapings or (keratoconjunctivitis), a generalised where possible. biopsy. Confirmation is made by direct vesicular skin eruption complicating fluorescent antibody tests, by isolation of Infectious agent chronic eczema or more rarely the virus from oral or genital lesions or Human herpes simplex virus (HSV) types encephalitis. other sites, or by detection of HSV DNA 1 and 2 cause disease. Features of gingivostomatitis include by nucleic acid testing in lesion or spinal ulceration of the tongue, gums, lips and fluid. Techniques are also available to Identification anterior buccal mucosa, severe systemic differentiate type 1 from type 2 antibody Clinical features toxicity and lymphadenopathy. if required. Cold sores are the most common manifestation of herpetic infection and Reactivation of latent viral infection in the Incubation period are characterised by a localised primary dorsal root ganglia results in cold sores The incubation period varies from two to lesion, latency and a tendency to local appearing as clear vesicles on an twelve days. recurrence. erythematous base. These usually occur on the face and lips and crust and heal in Public health significance In children with and a few days. This reactivation may be and occurrence immunosuppressed patients, herpes precipitated by trauma, fever, Asymptomatic infections with HSV type 1 simplex virus may disseminate causing a environmental conditions such as windy virus are common. Seventy to ninety per generalised eruption that requires days, sunburn or intercurrent disease. cent of adults have circulating antibodies hospitalisation for intravenous antiviral to HSV type 1 virus indicating previous HSV type 2 therapy. Herpes simplex may become infection. chronic in patients with HIV infection This virus is the usual cause of genital with recalcitrant crusted lesions and herpes although this can also be caused HSV type 1 is a common cause of ulceration. Herpes simplex may be by type 1 virus. Genital herpes occurs meningoencephalitis. Vaginal delivery in complicated by mainly in adults and is sexually pregnant women with active genital which is often more disabling than the transmitted. Primary and recurrent infection carries a high risk of infection itself. Herpes simplex virus infections occur, with or without disseminated visceral infection, infection may cause severe extensive symptoms. encephalitis and death to the newborn. disease in immunosuppressed The principal sites of primary disease in HSV type 2 is frequently associated with individuals. women are the cervix and vulva. sexually transmitted infections and HSV types 1 and 2 generally produce Recurrent disease generally involves the 20–30% of adults have antibody distinct clinical syndromes depending on vulva, perineal skin, legs and buttocks. In evidence of exposure. The prevalence is the portal of entry. men, lesions appear on the glans penis greater in socio-economically or prepuce, and in the anus or rectum of disadvantaged groups and those with HSV type 1 those engaging in anal sex. Other genital multiple sexual partners. The primary infection may be mild and or perineal sites as well as the mouth generally occurs in early childhood may also be involved in either gender Reservoir before the age of five years. About ten Humans. 88 The blue book: Guidelines for the control of infectious diseases

Mode of transmission Emphasise personal hygiene to minimise Contact isolation is required for Contact with HSV type 1 in the saliva of the transfer of infectious material. Wear disseminated severe infections and for carriers is the most important mode of gloves when in direct contact with infected neonates because of the risk to spread. Contact of health care workers infectious lesions and wash hands with other neonates or pregnant women. with patients who are shedding HSV may soap and water afterwards. Anogenital herpes result in an infection of the tip of the Use of latex condoms during sexual Patients should be fully screened for finger (herpetic ). It begins with intercourse decreases the risk of other STIs, including HIV infection, on intense itching and pain and is followed infection. their first presentation. by vesicle formation and then ulceration. Control of case For initial attack or infrequent recurrent Transmission of HSV type 2 to non- Non-genital herpes attacks treatment usually consists of immune adults is usually by sexual For symptomatic treatment of minor valaciclovir, famciclovir or aciclovir. For contact. attacks, use povidone iodine 10% paint suppression of frequent recurrent attacks applied three times daily. Also consider aciclovir or valaciclovir are generally Period of communicability topical antiviral therapy. Therapy should used. Consult the current version of Secretion of virus in the saliva may occur be self-initiated and commenced at the Therapeutic guidelines: antibiotic up to seven weeks after recovery from earliest sign of onset. Consult the current (Therapeutic Guidelines Limited). stomatitis. version of Therapeutic guidelines: If there is breakthrough during Patients with primary genital lesions are antibiotic (Therapeutic Guidelines prophylaxis, higher doses may be infective for seven to ten days. Those Limited). successful. Relapse may occur at the with recurrent disease are infectious for Sun protection is important in preventing cessation of prophylaxis. four to seven days with each episode. recurrences of facial herpes simplex. Control of contacts Susceptibility and resistance Specialist advice on systemic antiviral None applicable. Everyone is susceptible to infection. The treatment should be sought for: Control of environment disease does not usually confer • severe primary or severe recurrent None applicable. protective immunity because the virus attacks tends to become latent in dorsal root Outbreak measures • attacks complicated by erythema ganglia of the spine where it may None applicable. become reactivated at a later date. multiforme • primary or recurrent attacks in HIV- Control measures infected patients or the Preventive measures immunosuppressed. No vaccine is currently available. Patients with active lesions should have Health education and personal hygiene no contact with newborns, children with should be directed toward minimising burns or eczema and immunosuppressed transfer of infectious material and patients. Consider caesarean section reducing the risk of exposure to high risk before the membranes rupture when groups. primary or recurrent genital infections occur in late pregnancy to minimise the risk of neonatal infection. The blue book: Guidelines for the control of infectious diseases 89

Human immunodeficiency virus or acquired immunodeficiency syndrome

Victorian statutory requirement • Pneumocystis carinii pneumonia The interval from HIV infection to the Both HIV infection and AIDS are Group D • oesophageal diagnosis of AIDS ranges from about nine notifications. A separate notification form months to 20 years or longer, with a • Kaposi’s sarcoma is required for HIV and AIDS diagnoses. median of 12 years. There is a group of Written notification is required within five • chronic herpes simplex infection people with a more rapid onset of days of the initial diagnosis. • cryptococcosis disease who develop AIDS within three to five years of infection. Treatment with School exclusion is not required unless • cryptosporidiosis antiretroviral drugs and disease-specific the child has a secondary infection. • toxoplasmosis prophylaxis has resulted in an 80% Infectious agent • cytomegalovirus infection reduction in AIDS-associated illnesses. Human immunodeficiency virus (HIV) • mycobacteriosis Public health significance types 1 and 2 are a member of family and occurrence retroviridae. A number of subtypes exist • lymphoma Occurrence is worldwide. There were 40 within HIV–1 and HIV–2. • HIV encephalopathy million people living with HIV/AIDS by Identification • HIV wasting disease the end of 2001 and in 2000 three Clinical features Method of diagnosis million people died from HIV-related AIDS is a severe, life-threatening disease Careful history and physical examination illnesses. The vast majority of HIV that represents the late clinical stage of looking for risk factors and clinical infections occur in developing countries. infection with the HIV. Several weeks manifestations of immunodeficiency are For the period 1983 to 2003 there was a after infection with HIV, a number of necessary. cumulative total of 4680 HIV diagnoses infected individuals will develop a self- Diagnostic testing includes: in Victoria. This represents about 21% of limited glandular fever-like illness lasting • detection of HIV antibody by the ELISA Australia’s total. Males accounted for for a week or two. Infected persons may screening test and confirmation by 94% of the diagnoses. Male to male then be free of clinical signs or Western blot analysis sexual contact including homosexual and symptoms for months or years. bisexual contact accounts for the • detection of the viral p24 antigen in Treatment with antiretroviral medication majority of new diagnoses in men. In serum has resulted in fewer cases of AIDS. The females, heterosexual contact and burden of illness is now increasingly due • PCR tests to detect pro-viral DNA injecting drug use are the most common to non-AIDS infections, toxicities related sequences risk factors. to antiretroviral therapy including • HIV culture, although this is only Reservoir changes in body shape and metabolic performed in certain special clinical Humans. markers such as diabetes and high situations. cholesterol, and neurological and Mode of transmission Incubation period psychiatric manifestations of HIV. HIV can be transmitted from an infected The period from infection to the primary Untreated individuals are at risk of person by: seroconversion illness is three to eight specific opportunistic infections and weeks. The period from infection to • Sexual exposure to infected semen, malignancies and a range of other AIDS development of anti-HIV antibodies is vaginal fluids and other infected body indicative diseases. Major diseases that three weeks to three months. fluids during unprotected sexual may be indicative of AIDS include: intercourse with an infected person. This includes oral sex. 90 The blue book: Guidelines for the control of infectious diseases

• Inoculation with infected blood, blood Susceptibility and resistance • use of appropriate infection control products and through transplantation Everyone is susceptible to infection. measures in all premises where skin of infected organs such as bone grafts penetration is carried out, for example The presence of other sexually or other tissues, or by artificial electrolysis, tattooing or body piercing transmitted infections, especially those insemination with infected semen. with skin or mucosal ulceration, may • blood and blood products for • Breastfeeding of an uninfected infant increase susceptibility. transfusion and the donors of tissues by an HIV-positive mother. and body fluids such as semen should Interventions that decrease the risk of Control measures be tested for the presence of markers vertical transmission from an infected Preventive measures of HIV Preventive measures for HIV centre on woman to her child include • sharps injuries, including needle stick personal and institutional factors. antiretroviral therapy during pregnancy injuries, and parenteral exposure to and caesarean section. Avoiding Personal factors include: laboratory specimens containing HIV breastfeeding also decreases • public education on the use of should be dealt with according to transmission. With these interventions condoms and safer sex practices Infection control guidelines for the the risk of mother to child transmission prevention of transmission of infectious • public education should stress that is less than 5%. If there is no diseases in the health care setting having unprotected sex with unknown intervention, the risk of mother to child http://www.icg.health.gov.au/ HIV transmission has been estimated or multiple sexual partners and sharing to be 20–45%. needles (drug users) increases the risk • non-occupational exposure to infected of infection with HIV blood or body fluids should be assessed • Sharps injuries including needle stick and managed according to Australian • unprotected sexual intercourse with injuries or other exposure to blood and National Council on AIDS, Hepatitis C persons with known or suspected HIV body fluids. The rate of seroconversion and related diseases guidelines, infection should be avoided following a needle stick injury involving http://www.ancahrd.org/pubs/ HIV infected blood is said to be less • HIV-infected persons should be offered Control of case than 0.5%, but this is dependent on the confidential counselling and access to Standard precautions (see Appendix 3) type of needle stick injury (deep versus screening and treatment for sexually apply to all patients. shallow) and the viral load of the transmissible infections and infected person. appropriate antiviral therapy for HIV Additional transmission-based precautions apply for specific infections • care should be taken when handling, Period of communicability that occur in AIDS patients such as using and disposing of needles or other All antibody positive persons carry the tuberculosis. Equipment contaminated sharp items HIV virus. with blood or body fluids should be Infectivity is presumed to be life long, • use of needle exchange programs by cleaned and then disinfected or sterilised although successful therapy with injecting drug users should be as appropriate. facilitated. antiretroviral drugs can lower the viral Patients and their sexual partners should load in blood and semen to undetectable Institutional factors include: not donate blood, organs or other human levels. • use of appropriate infection control tissue. measures by all health care and All HIV positive persons should be emergency workers evaluated for the presence of tuberculosis. The blue book: Guidelines for the control of infectious diseases 91

Treatment Special settings Additional sources of information Anti-retroviral drug therapy is used to Health care workers • Australian Government Department of treat established HIV infection. As such Registration boards should be consulted Health and Family Services 1997, treatment is specialised and constantly in relation to their policies regarding Contact tracing manual – A practical changing, only those doctors health care workers with blood-borne handbook for health care providers experienced in HIV management should viruses. For example, the Medical managing people with HIV, viral prescribe antiretroviral therapy. For Practitioners Board of Victoria has a hepatitis, other STDs and HIV-related further information, see the current policy on medical practitioners and tuberculosis, Australian Government edition of the Therapeutic guidelines: medical students who carry a blood- Department of Health and Family antibiotic (Therapeutic Guidelines borne virus, which is available at Services. Limited). Other treatment includes http://medicalboardvic.org.au. • Australian Government Department of specific treatment or prophylaxis for the Recommendations are also included in Health and Aged Care 2000, National opportunistic infectious diseases that Infection control guidelines for the HIV/AIDS strategy 1999–2000 to result from HIV infection. prevention of transmission of infectious 2003–2004 – changes and challenges, diseases in the health care setting, Control of contacts Australian Government Department of http://www.icg.health.gov.au If a person is diagnosed as having HIV Health and Aged Care, infection, the diagnosing practitioner has Antenatal care http://www.health.gov.au a responsibility to ensure that sexual and Antenatal care should include a • Australian National Council on AIDS, needle-sharing contacts are followed up comprehensive assessment of HIV risk Hepatitis C and Related Diseases, where possible. factors. Women found to be at higher risk www.ancahrd.org Assistance with partner notification may of HIV infection or exposure should be • Australasian Society for HIV Medicine Inc be provided by Department of Human encouraged to undergo HIV antibody 2001, HIV/Viral hepatitis – A guide for Services through its partner notification screening. primary care, http://www.ashm.org.au/ officers. Other settings • Centers for Disease Control 2001, Pre and post-test counselling must be All workplaces should have policies and ‘Updated U.S. Public health service provided for all contacts seeking HIV procedures in place regarding action to guidelines for the management of testing. be taken in the event of a blood spill or sharps injury. Further information can be occupational exposures to HBV, HCV, Control of environment found in Infection Control Guidelines: for and HIV and recommendations for The procedure for dealing with spills of the prevention of transmission of postexposure prophylaxis’, MMWR, vol. blood and body fluids is in Appendix 5. infectious diseases in the health care 50, RR11, pp. 1–42, http://www.cdc.gov/mmwr Outbreak measures setting. http://www.icg.health.gov.au The epidemiology of HIV is closely • Fleming, DT & Wasserheit, JN 1999, International measures ‘From epidemiological synergy to monitored in Victoria and public health WHO initiated a global prevention and action is informed by enhanced public health policy and practice: the control program in 1987. Since 1995, the contribution of other sexually epidemiological information notified to global AIDS program has been the Department. transmitted diseases to sexual coordinated by UNAIDS. Nearly all transmission of HIV infection’, Sexually countries have developed an AIDS transmissible infections, vol. 73, pp. prevention and care program. 3–17. 92 The blue book: Guidelines for the control of infectious diseases

• Venereology Society of Victoria 2002, National management guidelines for sexually transmissible infections, Venereology Society of Victoria, http://www.mshc.org.au • Victorian Department of Human Services 2002, Victorian HIV/AIDS strategy 2002–2004, http://www.health.vic.gov.au/ideas • Working Group of the UK Chief Medical Officer’s Expert Advisory Group on AIDS 2000, Review of the evidence on risk of HIV transmission associated with oral sex – report of a working group of the UK Chief Medical Officer’s Expert Advisory Group on AIDS, Department of Health, London. The blue book: Guidelines for the control of infectious diseases 93

Hydatid disease (echinococcosis)

Victorian statutory requirement The Casoni skin test has now been are the major intermediate hosts. Sheep Notification and school exclusion are not replaced by serological tests for hydatid eat the worm eggs from pasture required. disease. These include fluorescent contaminated with dog faeces. These antibody (FA) and indirect hatch inside the sheep, forming cysts. Infectious agent haemagglutination antibody testing. The life cycle is completed when dogs Echinococcus granulosus (dog tapeworm) are infected through eating the offal of is the causative agent. Incubation period infected livestock or wild animals, The incubation period varies from particularly the liver and lung. Identification months to years. Clinical features Mode of transmission Hydatid disease in humans is produced Public health significance Human infection occurs by hand-to- by cysts that are the larval stages of the and occurrence mouth transfer of tapeworm eggs from tapeworm Echinococcus. Brood capsules Hydatid disease occurs worldwide and is dog faeces. The larvae penetrate the are formed within cysts,cysts containing mainly associated with sheep farming. intestinal mucosa, enter the portal 30–40 protoscoleces. Each of these is Notification of hydatid infection ceased system and are carried to various organs capable of developing into a single in Victoria earlyVictoria early in 2001. In where they produce cysts in which tapeworm. Symptoms depend on the the decade prior to 2001 there was an infectious protoscoleces develop. location of the cyst within the body and average of 16 notifications per year. Most The important life cycle is dog-sheep- develop as a result of pressure, leakage of these represented infections acquired dog. A dingo-wallaby-dingo (or wild dog) or rupture. The most common site for the overseas. Occasional cases of recently sylvatic cycle also occurs. A dog-wild cysts is the liver. Less commonly brain, acquired hydatid infection have been pig-dog cycle has been recognised and lungs and kidneys are affected. The identified in visitors to rural areas in poses a special risk for wild pig-hunters. heart, thyroid and bone are uncommonly Victoria where there are infected sheep affected. or dingoes. Urban dogs which Period of communicability Cysts in the body may remain viable or accompany travellers are often Hydatid disease is not transmitted from die and calcify. They may be detected on suspected of being an intermediary of person to person. routine X-rays. The prognosis is generally the cycle of transmission to humans. Dogs pass eggs approximately seven good and depends on the site and People who trap wild dogs are similarly weeks after infection. In the absence of potential for rupture and spread. Sudden at risk. reinfection this ends within one year. rupture of the brood capsules and liberation of the daughter cysts may Reservoir Susceptibility and resistance cause fatal anaphylaxis. Persons who The domestic dog and other canids, Young children are more likely to be have a calcified cyst detected on X-ray definitive hosts for E. granulosus, may infected as they are more likely to have may still have active infection. harbour thousands of adult tapeworms closer contact withcontact with infected without being symptomatic. Method of diagnosis dogs and they are less likely to have Diagnosis may be made plain X-ray, Felines and most other carnivores are appropriate hygiene habits. There is no ultrasound or CT scan. If a cyst ruptures, normally not suitable hosts for the evidence to suggest children are more appropriate examination for parasite. susceptible to infection than adults. protoscoleces, brood capsules and cyst Intermediate hosts include herbivores, wall in sputum, vomitus, faeces or urine sheep, cattle, goats, pigs, horses, should be undertaken. kangaroos, wallabies and camels. Sheep 94 The blue book: Guidelines for the control of infectious diseases

Control measures Control of environment Preventive measures Dogs kept in and around the case’s Basic hygiene such as washing hands house may require veterinary screening with soap after gardening or touching the for hydatid infection. dog and washing vegetables that may In general, dogs should be treated with have been contaminated by dog faeces, an anti-tapeworm medication such as are are important in prevention of this praziquantel every six weeks in rotation disease. with a broad spectrumbroad-spectrum Control of case de-worming preparation to prevent Surgery is often the treatment of choice disease in dogs and break the life cycle for infection with Echinococcus of the parasite. granulosus, sometimes combined with Review practices that may have led to prolonged high-doses of the drug infection. In particular, restrict dog albendazole. Percutaneous drainage with access to raw offal from infected sheep ultrasound guidance plus prolonged high- or kangaroos to prevent the life cycle dose albendazole theraphytherapy has continuing. Incinerate or deeply bury been effective for liver cysts. Praziquantel infected organs from dead intermediate followed by prolonged high-dose animal hosts. albendazole theraphytherapy is used if there is cyst spillage from trauma or Outbreak measures surgery. Consult the current version of Not applicable. Therapeutic guidelines: antibiotic (Therapeutic Guidelines Limited). Additional sources of information Specialist infectious disease advice • Victorian Department of Primary should be sought. Industries, www.dpi.vic.gov.au Control of contacts • Victorian Department of Sustainability Persons carrying the infection are not and Environment, www.dse.vic.gov.au contagious to others. Encourage contacts to practice appropriate hygiene and to report early any compatible symptoms. The blue book: Guidelines for the control of infectious diseases 95

Impetigo (school sores)

Victorian statutory requirement common in the nappy area. Most cases are no longer infectious after Notification is not required. Complications are rare. 24 hours of appropriate antibiotic therapy. School exclusion: exclude until Staphylococcal skin infections rarely appropriate treatment has commenced. result in the more severe ‘scalded skin Susceptibility and resistance syndrome’ which varies from a diffuse Sores on exposed surfaces must be Everyone is susceptible to streptococcal scarlatiniform erythema to a generalised covered with a watertight dressing. and staphylococcal . bullous desquamation of the skin. Infectious agent Persons suffering from chronic Method of diagnosis Various strains of Streptococcus conditions producing breaks in the skin, Diagnosis should be confirmed by pyogenes, group A streptococci (GAS) such as eczema or atopic dermatitis, may isolation of the organism from skin and Staphylococcus aureus cause be at greater risk of impetigo. swabs. This also allows confirmation of disease. antibiotic susceptibility. Control measures Identification Preventive measures Incubation period Clinical features Good personal hygiene practices The incubation period is one to three Impetigo is a contagious superficial skin including a daily bath or shower. days for S. pyogenes and four to ten days infection seen mainly in children but it Emphasise the importance of not sharing for S. aureus. may occur at any age. The infection may toilet articles and of suitably covering present with mildly irritating blisters that Public health significance cuts and abrasions. become pustular and erode rapidly and occurrence Educate on modes of transmission and leaving a honey-coloured crust. It often Occurrence is worldwide. Impetigo is a possible complications of impetigo and appears around the nose and mouth. rapidly spreading, highly contagious skin reinforce the importance of treating Local lymph nodes may be enlarged and infection that frequently occurs in cases promptly. the affected child may occasionally be children’s settings such as day care Control of case acutely ill. centres, kindergartens and schools. General therapy may consist of saline or Impetigo due to S. pyogenes is not Reservoir soap and water or aluminium acetate solution or potassium permanganate generally associated with Humans. but may rarely cause a solution to remove crusts. glomerulonephritis. This usually occurs Mode of transmission For cases where Streptococcus pyogenes three to eight weeks after the skin The organisms enter through damaged is suspected or confirmed treatment is infection. Skin GAS infections may be an skin and are transmitted through direct generally phenoxymethylpenicillin or important risk factor for rheumatic heart contact with patients or asymptomatic benzathine penicillin. disease, independent of throat GAS carriers. Nasal carriers are particularly Patients with penicillin hypersensitivity carriage. likely to transmit disease. It is rarely are generally given roxithromycin. Impetigo in the neonate often follows S. transmitted by indirect contact with For cases where Staphylococcal aureus is aureus colonisation of the nose, objects. suspected or confirmed mupirocin umbilicus, rectum or conjunctivae. The Period of communicability ointment is the usual treatment. lesions are initially vesicular and become If untreated, purulent discharges may seropustular and may develop bullae remain infectious for weeks to months. (). Lesions are most 96 The blue book: Guidelines for the control of infectious diseases

For severe, widespread or longstanding • avoiding direct contact with lesions on Treat confirmed cases with appropriate infections flucloxacillin, cephalexin or the affected person if possible antibiotics. roxithromycin may be used as each of • remembering to wash hands regularly • Draining lesions should be covered at these drugs is active against both S. particularly after touching the lesions all times with a dressing. aureus and S. pyogenes. or scabs of the infected person and • Trace and determine source of In all cases see the current edition of the use gloves where possible infection. Consider: Therapeutic guidelines: antibiotic • refer symptomatic contacts for (Therapeutic Guidelines Limited). – examining staff for active lesions appropriate treatment. anywhere on the body General advice for patients with impetigo Control of environment includes: – obtaining nasal swabs from staff to See Control of contacts, above. detect asymptomatic carriers and • consider using anti-bacterial soap for treating accordingly. bathing for two to three weeks Outbreak measures Child care settings and schools • Promote the need for good hand • dispose of soiled dressings • Exclude all confirmed cases and refer washing and hygiene practices among appropriately suspected cases for appropriate staff and visitors to the unit where the • emphasise the need for hand washing, treatment and management. outbreak has occurred. especially after changing dressings, • Emphasise the need for good hand • Investigate adequacy of infection and the importance of avoiding sharing washing procedures for all staff and control procedures and the availability toilet articles, towels, clothing or bed children. of hand washing facilities including linen antiseptic hand solutions. • Advise parents of other children and • avoid scratching or touching the staff who may have had contact with lesions to prevent spread to other Additional sources of information the cases to remain vigilant for signs of areas of the body • Centers for Disease Control and impetigo and seek treatment if Prevention, Group A Streptococcal • advise on the importance of symptoms develop. (GAS) Disease, www.cdc.gov/ncidod completing the recommended • Ensure that sores on exposed skin antibiotic course. • Shelby-James, TM, Leach, AJ, surfaces of confirmed cases are Carapetis, JR, Currie, BJ, Mathews, JD Patients must be excluded from school covered with a watertight dressing 2002, ‘Impact of single dose or child care services until antibiotic while at school. azithromycin on group A streptococci treatment has commenced. Sores on Hospital nursery or maternity ward in the upper respiratory tract and skin exposed surfaces such as scalp, face, • Cohort cases and contacts until all of Aboriginal children’, Pediatr Infect Dis hands or legs must be covered with a have been discharged. Staff working J, vol. 21, no. 5, pp. 375–80. watertight dressing. with colonised infants should not work Control of contacts with non-colonised newborns. Advice to household members should • Obtain swabs from discharging lesions include: to determine organism. • education about the mode of transmission Impetigo (school sores) information sheet

What is impetigo? How long does it take until When can children return to Impetigo is a contagious skin infection symptoms start? school or child care? usually caused by either Staphylococcus The incubation period will vary Children can return to school or child or Streptococcus bacteria. It is most depending on the particular bacteria. care after treatment has started and the commonly found in children although it It is usually 1–3 days for streptococcal sores are completely covered with a may also occur in adults. and 4–10 days for staphylococcal watertight dressing. Impetigo may affect skin anywhere on infections. How can impetigo be prevented? the body but commonly occurs in the • Encourage children to wash their area around the nose and mouth. It first How is impetigo treated? hands regularly and always use their appears as a small itchy, inflamed area of • Impetigo is most often treated with own towel and facecloth. skin which blisters. The blisters rupture, antibiotics, either orally or with release a yellow fluid and develop honey- bactericidal ointment. It is important to • Cut your child’s nails short and coloured crusts and form scabs. New follow the recommended treatment encourage them not to scratch scabs blisters develop in the same area or in and complete the course of antibiotics. or pick their nose. different parts of the body and may ooze • Treatment involves washing the sores • Keep injured areas of skin clean and fluid which is highly contagious. and crusts every 12 hours or as covered to minimise the chance of any Impetigo is easily diagnosed by the directed with the prescribed soap or bacterial infection, including impetigo. doctor. Occasionally a skin swab may be lotion. After each wash pat dry. • Always wash your hands after touching taken to identify the bacteria responsible • Healing should begin within 3 days and sores or scabs and use gloves if for the infection. the infection eliminated in 7–10 days. possible when treating infected children. How is impetigo spread? • If the sores spread and get worse Impetigo is extremely contagious. It can despite treatment or the child • Keep children with impetigo away from be spread from one person to another becomes unwell with fever, see your other children for the period of through touch or shared items such as doctor. exclusion. This is until antibiotic clothes and towels. However, a person • Cover the sores with an airtight treatment has commenced and the can also spread it to another part of their dressing if the child is returning to sores are covered with a watertight own body through scratching or picking school in order to reduce the risk of dressing. at the blisters and scabs. spreading the infection. Further information • The child’s clothes, towels and Who is most at risk of • Your local doctor bedclothes should be changed at least developing impetigo? • Better Health Channel, once a day. Children are most at risk of developing www.betterhealth.vic.gov.au • Always remember to wash your hands impetigo. Children and adolescents may • Victorian Department of Human after touching scabs or sores or be more likely to develop impetigo if the Services, 1300 651 160 skin has already been irritated or injured handling infected clothing. by other skin problems such as eczema, How long does impetigo remain insect bites, skin allergy or recent cuts or infectious? abrasions. If untreated, oozing sores remain infectious for as long as they persist.

Department of Human Services www.health.vic.gov.au/ideas 98 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 99

Infectious mononucleosis (glandular fever)

Victorian statutory requirement ELISA IgG for nuclear antigen,antigen Period of communicability Notification and school exclusion are not takes two to three months to become The period of communicability is required. positive. prolonged. Pharyngeal excretion may persist for a year or more after infection. Infectious agent Incubation period Twenty per cent or more of EBV antibody Epstein-Barr virus (EBV) is the causative The incubation period is from four to six positive healthy adults are long term agent. weeks. oropharyngeal carriers.

Identification Public health significance Susceptibility and resistance Clinical features and occurrence Everyone is susceptible to infection. EBV is an acute viral infection affecting Occurrence is worldwide and widespread Infection confers a high degree of mainly young adults. Clinical features in early childhood in developing resistance. Reactivation of EBV may include fever, generalised countries. In developed countries the occur in immunosuppressed individuals. lymphadenopathy and a sore throat that age of infection is delayed until older usually is an exudative childhood or young adulthood and is Control measures pharyngotonsillitis. most commonly seen in high school and Preventive measures university students. Only 50% of those occurs in 50% of patients There is no vaccine available. Basic infected will develop clinical disease. and jaundice in 4%. In young children the hygiene can help prevent many diseases disease is mild or asymptomatic. The Epstein-Barr virus appears to play a including glandular fever. Teach children duration of symptoms varies from one to causative rolecausative role in: not to share spoons, forks, cups, soft drink cans or sports water bottles. Adults several weeks. A variety of uncommon • Burkett’s lymphoma which is a should not share personal items such as complications have been described and monoclonal tumor of B cells glasses, cigarettes, lipstick or other items fatalities are exceedingly rare. A chronic in highly malarious that may be covered in saliva. form of the disease is suggested as one zones of the world of the causes of the chronic fatigue Control of case • nasopharyngeal carcinoma, particularly syndrome. Isolation is not necessary. There is no among groups from China and Taiwan Herpes virus 6, cytomegalovirus or treatment and antibiotics are not • hairy cell leukemia. toxoplasmosis may cause a syndrome indicated. resembling glandular fever, both both Reservoir Control of contacts clinically and haematologically. Humans. Not applicable. Method of diagnosis Control of environment Diagnostic ELISA IgG and IgM antibody Mode of transmission Not applicable. EBV is transmitted by person to person testing can be conducted on sera. A full Special settings spread by the oropharyngeal route via blood examination characteristically People with active EBV infection should saliva, classically by ‘tongue-kissing’. shows mononucleosis and a lymphocyte not visit people receiving organ Young children may be infected by saliva count of 50% or more. PCR testing is transplants including bone marrow. available foravailable for CSF or tissue on the hands of attendants or on toys. specimens through VIDRL. Virus can also Outbreak measures be isolatedbe isolated from throatfrom Not applicable. throat swabs or nasopharyngealor nasopharyngeal aspirates. 100 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 101

Influenza

Victorian statutory requirement performed on blood specimens taken Most human infections are caused by Influenza (Group B disease) must be during the acute and convalescent either type A or B influenza viruses. Type notified in writing within five days of stages. A has been associated with widespread laboratory confirmation. The diagnosis can be confirmed in the epidemics and pandemics, while type B has been infrequently associated with School exclusion: exclude until well. laboratory by one or more of the following: regional epidemics, and type C is only Infectious agent rarely associated with human infection. • detection of influenza virus by culture Influenza virus (types A, B and C) is the or nucleic acid testing, most commonly Influenza A is sub-typed further. It has causative agent. polymerase chain reaction (PCR) two surface antigens (proteins) that are used for sub-typing: haemagglutinin (H) Identification testing and neuraminidase (N). Since 1918 the Clinical features • demonstration of a significant rise, only three influenza A sub-types known Influenza is an acute respiratory disease. i.e. fourfold increase in the influenza- to usually cause human disease are Symptoms include fever, headache, specific antibody titre between a H1N1, H2N2 and H3N2. Other subtypes myalgia, lethargy, coryza, sore throat and serum sample collected in the acute such as HSN1 are very rare. cough. Infections in children, particularly phase and another sample collected in type A and B (H1N1) may also be the convalescent phase two to three Influenza viruses are formally named associated with gastrointestinal weeks after onset of symptoms according to their type (A, B or C), their symptoms such as nausea, vomiting and sub-type antigenic characterisation and • a single high influenza-specific diarrhoea. Croup is a common location of first isolation; for example, antibody titre of five dilutions or presentation in children. influenza A (H1N1) or New Caledonia. greater. This means a titre of 160 or Most symptoms resolve within two to greater, or 128 or greater, depending The emergence of completely new sub- seven days although the cough may upon the titration method. types of type A virus (antigenic shift) persist longer. Complications of influenza occurs at irregular intervals and is include middle ear infections, secondary Incubation period responsible for pandemics. Minor bacterial pneumonia and exacerbation of The incubation period is one to four days. antigenic changes (antigenic drift) are underlying chronic health conditions. responsible for annual epidemics and Public health significance regional outbreaks. During influenza epidemics, patients with and occurrence early influenza symptoms (fever >38ºC, Influenza occurs as pandemics, Reservoir plus at least one systemic symptom such epidemics, outbreaks and as sporadic Humans are the primary reservoir. as myalgia, and one respiratory cases. Animal reservoirs are suspected as symptom) have a 60–70% chance of Severe disease and complications such sources of new human subtypes and having influenza infection. as viral and bacterial pneumonia occur may occur particularly when people and Method of diagnosis primarily among the elderly and those livestock (for example pigs and poultry) A clinical diagnosis can be confirmed by debilitated by a chronic disease. live closely together. In 2004 an outbreak culture or antigen testing of appropriate of avian influenza (influenza A H5N1) In temperate zones outbreaks tend to respiratory specimens such as caused a number of human infections in occur in winter. In the tropics they often nasopharyngeal aspirate or nose and South East Asia. occur in the rainy season but outbreaks throat swabs, taken within five days of or sporadic cases may occur at any time. onset. Or it can be confirmed by serology 102 The blue book: Guidelines for the control of infectious diseases

Mode of transmission Hemisphere winter. It normally includes For sporadic cases isolation is often Influenza viruses are predominately representatives of both major influenza A unrealistic due to the delay in diagnosis. transmitted by airborne spread in subtypes (H1N1, H3N2) and B strain. If cases are still symptomatic they should aerosols but can also be transferred by Influenza vaccine is recommended on be advised to remain at home until well direct contact with droplets. Nasal the Australian Standard Vaccination and to avoid contact with high risk inoculation after hand contamination Schedule annually for all persons 65 persons. with the virus is also an important mode years and older. Control of contacts of transmission. Free annual influenza vaccine is provided Control of contacts may be of benefit in Direct contact is important, as the virus and recommended for the following high risk populations who should be will survive some hours in dried mucus groups in Victoria: advised to seek medical advice on particularly in cold and dry prophylaxis and to seek early medical • all people aged 65 years and older environments. review if symptoms develop. • all Aboriginal and Torres Strait Chemoprophylaxis with amantadine or a Period of communicability Islanders aged 50 years and older, and neuraminidase inhibitor may be It is probably communicable for three to those aged 15–49 years who are at considered in special circumstances five days from clinical onset in adults and high risk for the complications of against influenza A strains, for example in up to seven days and occasionally longer influenza including those with: residential institutions. The potential in young children. – chronic disease such as diabetes, value of chemoprophylactic drugs must Susceptibility and resistance heart, lung, kidney or liver disease be assessed against their side effects. When a new subtype appears, all people – decreased immunity Control of environment are susceptible except those who have – living in chronic care facilities Cases and carers should be advised lived through earlier epidemics caused by about the importance of hand washing, • all public hospital staff in both a related subtype. covering the mouth when coughing, outpatient and ward settings who sneezing into disposable tissues, and the Infection produces immunity to the provide direct care to patients, to appropriate cleaning or disposal of specific infecting virus, but the duration protect themselves and their patients. and breadth of immunity varies widely. contaminated objects. This is partly dependent on host factors, Annual influenza vaccination is also Outbreak measures the degree of antigenic drift in the virus recommended for staff working in The most important control measure to and the period of time since the previous nursing homes and other chronic care prevent serious morbidity and mortality infection. facilities to protect themselves and their patients. from influenza epidemics is appropriate immunisation. Investigations are generally Control measures Control of case restricted to outbreaks in groups at Preventive measures Symptomatic treatment alone or with the higher risk of complications (see Special The influenza vaccine in Australia is addition of a neuraminidase inhibitor, if settings, below). developed in time for the annual winter commenced within the first 36 hours of rise in ‘flu’ activity. The strains that are the onset of the illness, can shorten the An influenza results when contained in the vaccine are based on duration by two to three days. Consult antigenic shift leads to a new highly the circulating strains in the previous the current version of Therapeutic virulent influenza subtype for which there couple of years as well as those guidelines: antibiotic (Therapeutic is little or no immunity in the population. circulating in the previous Northern Guidelines Limited). Public health action in this setting may The blue book: Guidelines for the control of infectious diseases 103

involve a variety of measures to control Additional sources of information spread in the community. Victorian Infectious Disease Reference Special settings Laboratory, The flu report, Aged care facilities, health care facilities http://www.vidrl.org.au and child care centres are all special (during flu season). areas at high risk of influenza outbreaks. Aged care facilities Specific infection control measures should be implemented in the event of: • a laboratory-confirmed case of influenza • two or more cases of an acute respiratory illness consistent with influenza (’influenza-like illness’). Infection control measures include vaccination of any unvaccinated staff and residents, exclusion of sick staff members, cohorting of resident cases, active case finding and, in some settings, the use of antiviral treatment and prophylaxis. Health care facilities Outbreaks of an unidentified respiratory illness in a hospital setting including outbreaks of influenza-like illness are investigated jointly by the Department of Human Services and the hospital’s infection control unit. Child care centres Outbreaks of influenza or influenza-like illness in child care require exclusion of cases and may warrant prophylaxis for high risk contacts. The Department of Human Services can advise on prophylaxis and infection control procedures. 104 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 105

Invasive pneumococcal disease

Victorian statutory requirement Public health significance Susceptibility and resistance Invasive pneumococcal disease (Group B and occurrence Everyone is susceptible to infection, disease) requires notification in writing S. pneumoniae is one of the most however the risk of invasive disease is within five days of diagnosis. common causes of bacterial meningitis, highest for those aged less than two septicaemia and pneumonia worldwide. years and the elderly. Other risk factors Infectious agent Indigenous children in central Australia include prematurity and low birth weight, Streptococcus pneumoniae is a gram- have the highest reported rates of immunosuppressive therapy and positive Streptococcus of which 90 invasive pneumococcal disease exposure to tobacco smoke. Chronic serotypes are known to cause disease. worldwide. The overall incidence rate in illness such as asplenia, sickle cell Worldwide, approximately 23 serotypes Victoria is approximately 9 per 100 000 disease, cardiovascular disease, diabetes account for the majority of infections. population per year, with an overall case mellitus, cirrhosis, Hodgkin’s disease, fatality rate approaching eight per cent. lymphoma, multiple myeloma, renal Identification Rates of disease are highest in children failure, nephrotic syndrome, HIV infection Clinical features aged less than two years and persons and recent organ transplant are also risk Invasive pneumococcal disease aged 65 years and over. factors for infection. Immunity is thought commonly presents as septicaemia, to be serotype specific. meningitis and pneumonia. Septicaemia The prevalence of antibiotic resistance is and meningitis are more common in increasing. Approximately 12% of isolates Control measures in 2001 in Australia were resistant to children (with the exception of Aboriginal Preventive measures penicillin and five per cent were resistant children who present most commonly A 7-valent pneumococcal conjugate to third generation cephalosporins. The with pneumonia), while pneumonia is vaccine (7vPCV) and a 23-valent prevalence of antibiotic resistant differs more frequent in adults. Other clinical polysaccharide pneumococcal (23vPPV) by State and Territory. presentations include septic arthritis, vaccine are both available in Australia. peritonitis, pleurisy and pericardial Reservoir Approximately 86% of serotypes causing abscess. S. pneumoniae are commonly found in disease in non-Indigenous children in Method of diagnosis the upper respiratory tract of humans. Australia (55% in indigenous children) are Identification of the organism by contained in the 7vPCV, and 93% of culturing it from a normally sterile site Mode of transmission those causing adult disease are like blood or cerebrospinal fluid or by Respiratory droplets, direct oral contact contained in the 23vPPV. nucleic acid tests such as PCR. Rapid or indirect contact through articles In Australia the 23vPCV is recommended antigen detection tests are available but freshly soiled with respiratory discharges. on the Australian Standard Vaccnation they are of limited use in the diagnosis of Schedule for all persons aged 65 years Period of communicability invasive disease in children due to the and over, those in high risk groups and all Bacteria are communicable in respiratory frequency of pharyngeal pneumococcal Indigenous persons aged 50 years or infections, until discharge from the carriage. more. The vaccine is funded for all mouth and nose no longer contain persons aged 65 years and over and Incubation period virulent pneumococci in significant indigenous persons aged 50 years or The incubation period is one to three numbers. Penicillin renders patients with more, and those aged 15–49 years in days. susceptible strains non-infectious within certain high risk groups. 24–48 hours. 106 The blue book: Guidelines for the control of infectious diseases

The 7vPCV is recommended on the Outbreak measures ASVS for all children at two, four and six In outbreaks in institutions or in other months of age. From 1 January 2005 this closed population groups immunisation vaccine will be funded under the National could be considered. Immunisation Program. Refer to The Australian immunisation handbook Additional sources of information (National Health and Medical Research • Australian Government Department of Council). Health and Ageing, National Indigenous Pneumococcal and Influenza Program, Control of case http://www.health.gov.au Penicillin remains the treatment of choice until antibiotic sensitivities are • MJA 2000 ‘Pneumococcal disease in obtained. Patients who are allergic to Australia’, Medical Journal of Australia, penicillin may be given cephalosporins or vol. 173, Supplement. erythromycin for pneumonia and • Roche P & Krause V. ‘Invasive chloramphenicol for meningitis. Attempt pneumococcal disease in Australia’ to obtain blood or CSF specimens prior Comm Dis Intell, 2001, 24 (4); to commencing therapy however 505–519. treatment should not be delayed in • Victorian Department of Human children and infants, particularly if the Services, Victorian Pneumococcal and clinical presentation suggests Influenza Program, septicaemia or meningitis. Consult the http://www.health.vic.gov.au/ current version of Therapeutic guidelines: immunisation antibiotic (Therapeutic Guidelines Limited). Respiratory isolation may be warranted in hospitals for patients with infection due to an antibiotic resistant strain to reduce the risk of transmitting it to other patients at high risk of pneumococcal disease. Control of contacts Investigation of contacts is of no practical value. Control of environment Disinfect or destroy articles contaminated with discharges from the nose and throat or from other infected sites. The blue book: Guidelines for the control of infectious diseases 107

Japanese encephalitis

Victorian statutory requirement Method of diagnosis Incubation period Japanese encephalitis (Group A disease) Confirmation of JEV infection is made by The incubation period is usually six to must be notified immediately by either isolating the virus or by a rising sixteen days. telephone or fax followed by written antibody titre. Public health significance notification within five days. Laboratory evidence requires one of the and occurrence School exclusion: case should be following: The occurrence of JEV disease in Papua isolated until the fever subsides to • isolation of JEV from clinical material New Guinea and probable spread from prevent further mosquito bites. • detection of JEV viral RNA in clinical there to cause disease in the Torres Infectious agent material Strait Islands poses a significant threat to Australia. Suitable vector mosquitoes Japanese encephalitis virus (JEV) was • IgG seroconversion or a significant such as Culex annulirostris and first isolated in Japan in 1935. However, increase in antibody level or a fourfold vertebrate hosts in the form of water the disease Japanese encephalitis had rise in titre of JEV specific IgG proven birds are widespread across the been first described in Japan as early as by neutralisation or another specific mainland. There are also many wild pigs 1871, and since then has been found in test, with no history of recent JE or in north eastern Australia to act as Russia, most of the Far East and South yellow fever vaccination East Asia, and more recently it has amplifiers for the virus. There is a • JEV specific IgM in the CSF, in the spread to the Indian subcontinent and theoretical concern that migratory birds absence of IgM to Murray Valley Nepal. It is the principal cause of could carry the virus southwards in encephalitis, Kunjin and dengue epidemic viral encephalitis in the world, Australia, even as far as Victoria. viruses resulting in of the order of 50 000 clinical Reservoir cases annually. • JEV specific IgM detected in serum in the absence of IgM to Murray Valley Infection is maintained in enzootic cycles Of great concern to Australia was the encephalitis, Kunjin and dengue between birds and pigs: water birds introduction of the JEV into the Torres viruses, with no history of recent JEV or (herons and egrets) are the main Strait islands (1995) with two fatal cases yellow fever vaccination. reservoir for disseminating the virus of encephalitis and on to the mainland of whilst pigs are important amplifier hosts. Australia (Cape York) in 1998. Confirmation by a second arbovirus Pigs do not show signs of infection other Seropositive pigs were also detected on reference laboratory is required if the than abortion and , but have the mainland. The most likely source of case appears to have been acquired in continuing viremia allowing transmission the outbreak in the Torres Strait islands Australia. to man via mosquitoes. Humans and was Papua New Guinea, where the first Clinical evidence other large vertebrates such as horses human cases were detected in 1997. Febrile illness of variable severity are not efficient amplifying hosts, and are associated with neurological symptoms therefore ‘dead-end’ hosts for the JEV. Identification ranging from headache to meningitis or Clinical features encephalitis. Symptoms may include Mode of transmission Over 90% of Japanese encephalitis virus headache, fever, meningeal signs, stupor, In Asia the rice field breeding mosquitoes, infections are subclinical. Encephalitis is disorientation, coma, tremors, mainly Culex tritaeniorhynchus, usually its serious manifestation. This is clinically generalised paresis, hypertonia and loss transmit JEV. In the Torres Strait Islands indistinguishable from other viral of coordination. The encephalitis cannot outbreak virus was isolated from Culex encephalilitides and has a mortality of be distinguished clinically from other annulirostris mosquitoes which were 20–50%. Up to 50% of patients have central nervous system infections. considered to be the main vector serious sequelae. involved. Culex gelidus is a new potential vector in Australia if introduced from Asia. 108 The blue book: Guidelines for the control of infectious diseases

Period of communicability There is no evidence of transmission from person to person.

Susceptibility and resistance Infection with JEV confers lifelong immunity.

Control measures Preventive measures There is an effective vaccine available. It requires three doses on days zero, seven and 28 with a booster every three years. Control of case • Isolate patient and prevent mosquito access until fever subsides. • Investigate source of infection. Control of contacts Not applicable. Control of environment Search for and eliminate breeding sites of mosquito vectors in the urban area. Use mosquito repellents, mosquito nets and other methods of personal protection.

Outbreak measures Not applicable. The blue book: Guidelines for the control of infectious diseases 109

Kunjin virus disease

Arboviruses are viruses which are spread Fatalities are rare or absent. Very few Non-encephalitic illness by the bite of arthropods, particularly epidemiological studies have been Acute febrile illness with headache, mosquitoes. They are divided into carried out to determine the life cycle, myalgia and/or rash. alphaviruses and flaviviruses. nature and frequency of Kunjin virus Encephalitic disease infection in Australia. Victorian statutory requirement Acute febrile meningoencephalitis Method of diagnosis characterised by one or more of the Kunjin virus infection (Group B disease) Infection is confirmed by a significant following: requires notification within five days of rise in antibody titre to the virus in two diagnosis. • focal neurological disease or clearly blood specimens taken seven to ten days impaired level of consciousness School exclusion is not required. apart. • abnormal CT, MRI scan or EEG Infectious agent Laboratory evidence requires one of the • presence of pleocytosis in the CSF. Kunjin virus (KUNV) is a flavivirus and following: was first isolated from Culex annulirostris • isolation of Kunjin virus from clinical Incubation period mosquitoes collected in north material The incubation period is probably similar Queensland in 1960 and given the name • detection of Kunjin virus RNA in clinical to Murray Valley encephalitis virus of a nearby aboriginal clan living on the material (MVEV) disease. Mitchell River. It is closely related to the West Nile virus which was probably • IgG seroconversion or a significant Public health significance exported from the Middle East to New increase in antibody level or a fourfold and occurrence York in 1999 where it caused thousands rise in titre of Kunjin virus specific IgG Kunjin virus has many similarities to MVE of deaths in birds and horses and human proven by neutralisation or another virus and disease due to these two disease including fatal encephalitis. specific test viruses can only be distinguished by • Kunjin virus specific IgM detected in virological tests. This distinction is Identification the CSF important in periods when weather Clinical features patterns and other portends suggest that • Kunjin virus specific IgM detected in Serological surveys indicate that an outbreak of MVE virus may be serum in the absence of IgM to Murray is common. Two imminent in southeast Australia. This has Valley encephalitis, Japanese main clinical forms of disease have been a higher mortality rate and can be more encephalitis or dengue viruses. This is reported: mild disease and encephalitis. prevalent. Mild disease consisting of only accepted as laboratory evidence Serological surveys have shown that lymphadenopathy, fever, lethargy and for encephalitic illnesses. Kunjin virus infection has occurred over rash was first noted when two laboratory Confirmation of laboratory results by a wide areas of Australia infecting humans, workers acquired the infection in second arbovirus reference laboratory is and wild and domestic animals including Queensland in 1963. A few other similar required if the case occurs in areas of cattle, sheep and horses. Similarly to cases have been described in Australia Australia not known to have established MVE virus, Kunjin virus occasionally including some with additional muscle enzootic, endemic or regular epidemic spreads southward from the tropical weakness and fatigue. There has been a activity. north to central and southeastern comparatively small number (about six) Clinical evidence Australia after heavy rains. Kunjin virus of reported cases of encephalitis due to Clinical evidence may present as non- has been detected in Victoria on several Kunjin virus but one source quoted that a encephalitic, encephalitic and occasions since 1974, most recently in total of 15 cases occurred prior to 2000. asymptomatic disease. 2001. 110 The blue book: Guidelines for the control of infectious diseases

Reservoir The patient with suspected infection or Outbreak measures The virus is endemic in the tropical north friend or relative, should be asked to Search for unreported or undiagnosed of Australia and Sarawak where it has recall if in the month prior to onset of cases of encephalitis from the Murray- cycles of infection between birds and symptoms he or she had: Darling drainage basin. mosquitoes in enzootic foci. • been bitten by mosquitoes Mode of transmission • visited regions where arboviruses are Transmission occurs via mosquitoes, endemic particularly Culex annulirostris. • participated in recreational or other activities involving exposure to Period of communicability bushland or other mosquito habitat There is no evidence of person to person such as gardening, bushwalking, transmission. camping and picnicking. Susceptibility and resistance Control of contacts Infection confers lifelong immunity. Not applicable.

Control measures Control of environment To reduce or prevent virus transmission, Preventive measures interruption of human-mosquito contact There is no vaccine available. is required by: Kunjin virus infection can be prevented • suppression of the vector mosquito by: population • mosquito control measures • avoidance of vector contact and biting • personal protection measures such as times at dusk and dawn long sleeves and mosquito repellents • applying mosquito control measures in • avoidance of mosquito-prone areas local municipalities and vector biting times at dusk and • using personal protection measures dawn. such as long sleeves, long trousers, Control of case mosquito repellents Investigate the source of infection. • avoiding mosquito-prone areas. Search for unreported or undiagnosed cases of encephalitis from the Murray- Darling drainage basin. The blue book: Guidelines for the control of infectious diseases 111

Legionellosis (Legionnaires’ disease)

Victorian statutory requirement suspected. Culture is the gold standard Legionellosis (Group A disease) must be A non-pneumonic form of the infection and the only method by which human notified immediately by telephone or fax has been reported in other countries, specimens can be compared to followed by written notification within five presenting as a flu-like illness with fever environmental samples. Sputum samples days. and malaise lasting two to three days. for culture should be attempted for public Although there is said to be a high attack health reasons even if there are already School exclusion is not required. rate (95%), recovery is rapid with no positive serological or urinary antigen Infectious agent reported deaths. results. Legionellae are gram-negative bacilli. Method of diagnosis Nucleic acid testing There are currently more than 45 known Various methods of diagnosis for Detection of Legionella bacteria DNA in species of Legionellae. Those that are Legionellae infection include urinary clinical specimens using polymerase known to cause disease in Australia antigen testing, serology, culture and chain reaction (PCR) techniques is now include L. pneumophila, nucleic acid testing. available in some reference laboratories. L. longbeachae, L. micdadei and Urinary antigen testing The sensitivities and specificities of such L. bozemanii. L. pneumophila has 16 The Legionella urinary antigen test is the tests are variable. Legionella PCR identified serogroups. L. pneumophila most rapid and sensitive test currently requests should be discussed with the serogroup 1 has been identified as the available but will only detect the most Department of Human Services. cause of over 80% of cases in Victoria. common serogroup, Incubation period L. pneumophila serogroup 1. The antigen Identification The incubation period for Legionnaires’ test may not become positive for up to Clinical features disease is two to ten days. For Pontiac five days into the illness and should be Legionellosis has two recognised fever it is 24 to 48 hours. presentations: Legionnaires’ disease and repeated if the specimen was taken early Pontiac fever. Only Legionnaires’ disease in the illness and legionellosis is still Public health significance has been reported in Australia. strongly suspected. and occurrence Sporadic and epidemic forms of Legionnaires’ disease Serology Legionnaires’ disease occur in Australia. This is the pneumonic form of the illness. Positive Legionella antibody results (both Legionella infections are believed to There is often a severe flu-like prodrome IgG and IgM) are common in healthy account for 5–15% of community- with anorexia, malaise, myalgia and fever. adult populations. The presence of acquired . Upper respiratory tract symptoms such antibodies is not necessarily indicative of as runny nose and sore throat are rare. recent infection, especially in acute Outbreaks in Australia are generally phase sera. Diagnosis is made by the associated with man-made water Patients may present with any form of observation of a significant four fold systems including water-cooling towers pneumonia. As a group they are more increase in antibody titre between sera and spa baths. Home and institutional likely than other community acquired taken in the acute phase and during warm water systems are potential pneumonias to fulfill criteria for severe convalescence three to six weeks later. sources of Legionella infection but are disease. There are nearly always The two samples should be tested only rarely implicated in Australia. radiographic changes on CXR at the time concurrently (in parallel). Legionella outbreaks due to of presentation. Culture contaminated warm water systems are Other features commonly include Legionellae are fastidious organisms and regularly reported from other countries. hyponatraemia, fever greater than 40˚C, will not grow on conventional culture Legionellosis in hospitalised and severely renal impairment, diarrhoea and media. Culture for Legionellae must be immunosuppressed patients carries a confusion. specifically requested if the illness is much higher case fatality rate. 112 The blue book: Guidelines for the control of infectious diseases

Reservoir Susceptibility and resistance To minimise the risk of infection through Legionellae are ubiquitous in the There is a greater risk of more severe potting mix gardeners should be advised environment. They are often isolated legionellosis in persons aged 50 years to: from water and wet areas in the natural and over, regular smokers, and the • open the bag with care to avoid environment such as creeks, hot springs, immunosuppressed. More than 70% of inhalation of airborne potting mix seawater, woodchips, mulch and soil. infections in Victoria occur in patients • moisten the contents to avoid creating Potting mix is often colonised with over 50 years of age. The disease is dust Legionella species, particularly extremely rare in children. • wear gloves L. longbeachae. Nosocomial infections and infections in Legionellae also thrive in man-made severely immunosuppressed patients • wash hands after handling potting mix water systems if the water temperature is have a much higher case fatality rate (up even if gloves have been worn. maintained at 20°C–43°C, which favours to 40%) when compared to the 7% overall The same measures are also advisable the proliferation of the bacteria. These mortality rate in Victoria. when handling other gardening material may include cooling water towers Serological surveys identify Legionella- such as compost. associated with air-conditioning and specific antibody in 10–20% of healthy Only sterile water should be used in the industrial processes, spa baths and adults with no history of clinical cleaning of nebuliser medication household warm water systems for legionellosis. It is unclear whether this chambers and in the preparation of bathing. Shower-heads, nebulisers, antibody confers protective immunity. aerosol solutions for use in nebulisers or humidifiers, ultrasonic misting systems humidifiers. Flushing and instillation of and fountains have also been implicated. Control measures drinking water through nasogastric tubes Preventive measures Evaporative air conditioners like those in intubated or immunosuppressed Smoking is an important risk factor for commonly used for domestic cooling are patients should also only be performed developing symptomatic infection in not associated with Legionella infections. with sterile water. those exposed to Legionella bacteria, and Mode of transmission it is presumed cessation of smoking Control of case Legionellosis is generally transmitted reduces an individual’s risk of infection. Early antibiotic treatment improves survival. Empirical treatment of severe through inhalation of contaminated Although total eradication of Legionellae pneumonia with erythromycin to cover aerosols of water or of dust. from all artificial systems is not possible, the possibility of legionellosis is Microaspiration of contaminated water the risk of legionellosis can be minimised recommended. may be an important mode of through diligent maintenance of aerosol transmission in certain subgroups, such generating equipment and ensuring The patient’s environmental exposures as intubated patients and those receiving appropriate placement, design and during their incubation period are nasogastric feeding. compliance with legislation requirements established by interview and compared No human-to-human transmission has by owners. to other cases. been recorded. The blue book: Guidelines for the control of infectious diseases 113

Exposures of particular concern include: Outbreak measures • contact with hospitals and other health When two or more cases are linked in care facilities as a nosocomial source time and place an investigation is presents the greatest risk to others generally undertaken to identify likely Legionellae sources in the common area. • exposure to cooling towers Environmental sources sampled during • use of spas the Department of Human Services’ • use of potting mix. investigations such as cooling towers and spa baths are generally requested to The Department of Human Services be disinfected as a precaution while routinely investigates workplaces of laboratory testing is conducted. confirmed cases. Special settings Control of contacts Health care facilities Although there is no risk of person to When a nosocomial source is suspected, person transmission,amongs an active immediate testing and disinfection of search for other people who may have possible sources is undertaken and been exposed to the same active case finding is conducted environmental source is commonly throughout the institution. undertaken as part of the investigation of cases. Additional sources of information Control of environment • Victorian Department of Human After sampling of suspected Services Legionella Risk Management environmental Legionellae sources, an Program (including relevant immediate precautionary disinfection regulations), with an oxidizing biocide is undertaken. http://www.health.vic.gov.au/ Disinfection may be impractical and environment omitted if the source is organic such as garden potting mix. All cooling towers in Victoria are required by law to be registered and to undergo regular maintenance and water testing. Records of treatment may be sought and further disinfection may be required depending on the circumstances of the case, and in accordance with regulations. 114 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 115

Leprosy (Hansen’s disease)

Victorian statutory requirement Method of diagnosis endemic in tropical and subtropical Asia, Leprosy (Group B disease) must be Clinical suspicion is the crucial factor in Africa, Central and South America, notified in writing within five days of making an early diagnosis of leprosy in Pacific regions and the USA (Hawaii, diagnosis. non-endemic parts of Australia, like Texas, California, Louisiana, Puerto Rico). Victoria. Leprosy should always be School exclusion: exclude until approval considered in any undiagnosed patient Reservoir to return has been given by the with chronic skin lesions or a peripheral Humans. Secretary. Contacts are not excluded. neuropathy. This is particularly important Mode of transmission if they have spent more than brief Infectious agent The mode of transmission is not clearly periods in areas where the disease is Mycobacterium leprae is the causative established. The disease is probably endemic, or they have been a contact of agent. transmitted from person to person by a patient known to have leprosy. Identification aerosol with a high subclinical rate of Confirmation of diagnosis depends on infection. Household and prolonged Clinical features the form: close contact seem important. There is Leprosy is a slowly progressive bacterial anecdotal evidence that rarely it may be infection involving the cooler body • lepromatous disease requires transmitted by inoculation, such as by tissues, skin, superficial nerves, nose, demonstration of plentiful acid-fast contaminated tattoo needles. pharynx, larynx, eyes and testicles. Skin bacilli in skin or nasal smears. Skin smears are made by scraping a small lesions may occur as pale, anaesthetic Period of communicability amount of tissue fluid from a macules, or erythematous Leprosy is not usually infectious after superficial scalpel cut over a lesion and infiltrated nodules. three months of continuous treatment smearing it on a glass slide. Neurological disturbances are with dapsone or clofazimine, or after two manifested by nerve infiltration and • tuberculoid disease requires to three weeks of treatment with thickening with anaesthesia, neuritis, demonstration of typical granulomata rifampicin. paraesthesia and trophic ulcers. with sparse acid-fast bacilli, in biopsies of either skin or nerve lesions. Susceptibility and resistance The disease is divided clinically and by Everyone is susceptible to infection, laboratory tests into two overlapping Incubation period however study results have suggested a types: lepromatous and tuberculoid. The The incubation period is difficult to strong age-related susceptibility to being lepromatous type (multibacillary or non- determine. It probably ranges from nine infected or developing disease following immune form) is progressive with nodular months to 20 years with an average of close contact with a multi-bacillary case. skin lesions, slow symmetric nerve four years for and Children aged between five and nine involvement, numerous acid-fast bacilli in eight years for . years are at greatest risk. The risk of skin lesions and a negative lepromin skin progression to leprosy disease following test. The tuberculoid type (paucibacillary Public health significance infection is considered to be or immune form) is benign and non- and occurrence approximately the same as tuberculosis progressive with localised skin lesions, Leprosy is occasionally detected on which is approximately a 10% lifetime asymmetric nerve involvement, few routine refugee screening. The world risk. bacilli present in the lesions and a prevalence is estimated to be between positive lepromin skin test. ten to 12 million cases. The disease is 116 The blue book: Guidelines for the control of infectious diseases

Control measures Control of contacts Preventive measures Investigation of contacts and source of BCG vaccination has some protective infection, and early detection and efficacy and is recommended for treatment of new cases is required. neonates born to a person diagnosed Prophylactic BCG has resulted in a with leprosy. considerable reduction in the incidence of tuberculoid leprosy among contacts in Control of case some trials. Other studies are currently in Isolation of tuberculoid (paucibacillary) progress using a single dose of rifampicin cases is unnecessary. Isolation of as prophylaxis following leprosy lepromatous (multibacillary) cases is exposure. Currently, treatment of indicated until treatment is initiated, contacts in Australia is not particularly if nasal smears are positive. recommended. Nasal discharges of infectious patients should be disinfected or disposed of as Control of environment infectious waste. Not applicable. Rifampicin is the key to early control of Outbreak measures disease and rapid elimination of the risk Not applicable. of further transmission of infection to contacts. Minocycline can be used as an Additional sources of information alternative. • Fine, PE, Sterne, JA, Ponnighaus, JM et The minimal regimen recommended by al. 1997, ‘Household and dwelling WHO for lepromatous leprosy is triple contact as risk factors for leprosy in therapy with rifampicin, dapsone and northern Malawi’, Am J Epidemiol, vol. clofazimine for twelve months. 146, no. 1, pp. 91–102. For tuberculoid leprosy, the • World Health Organization, recommended regimen is rifampicin and http://www.who.int/topics/en/ dapsone for a period of six months (for detailed treatment regimens and duration, see current WHO recommendations). The blue book: Guidelines for the control of infectious diseases 117

Leptospirosis

Victorian statutory requirement The diagnosis is more commonly Mode of transmission Leptospirosis (Group B disease) must be confirmed serologically by the Primarily through contact of skin with notified in writing within five days of demonstration of a fourfold or greater water, moist soil or vegetation diagnosis. rise in Leptospira antibody in paired sera contaminated with the urine of infected taken in the acute phase and at least two School exclusion is not applicable. animals. The infection may also be weeks later. A single Leptospira micro transmitted through direct contact with Infectious agent agglutination titre of 400 or greater is urine or tissues of infected animals or by Leptospires are members of the order of also highly suggestive of acute infection. the inhalation of aerosols of Spirochaetes. Pathogenic leptospires contaminated fluids, such as may occur Incubation period belong to the species Leptospira in abattoirs. Ingestion of foods Typically 10 to 12 days, with a range of interrogans which is subdivided into contaminated with urine of infected rats four to 19 days. serovars. In Australia, the most common is an occasional route of infection. serovar is Public health significance L. interrogans serovar hardjo. Period of communicability and occurrence Direct transmission from person to Identification Leptospirosis occurs worldwide in person is rare. Leptospires may be developed and developing countries in Clinical features excreted in the urine for a month, but both rural and urban settings. The This group of zoonotic bacterial diseases urinary excretion in humans and animals disease is an occupational hazard for may present in a variety of for up to 11 months has been reported. farmers, sewer workers, miners, dairy and manifestations. Common clinical features abattoir workers and fish workers. It is a include fever (which may be biphasic), Susceptibility and resistance recreational hazard to bathers, campers headache, chills, a rash, myalgia and Immunity to the specific serovar follows and some sportspeople in infected inflamed conjunctivae. In endemic areas, infection, but may not protect against areas. many infections are either asymptomatic infection with a different serovar. Farmers, farm workers and meat industry or too mild to be diagnosed. Control measures workers in Victoria are the occupational More severe manifestations occur rarely Preventive measures groups most commonly affected by and include, meningitis, haemolytic There is no human vaccine available. leptospirosis. anaemia, haemorrhage into skin and General preventive measures include: mucous membranes, hepatorenal failure, Reservoir • education for the public on modes of jaundice, mental confusion, respiratory Serovars vary with the wild and domestic transmission, for example advise to distress and haemoptysis. animal affected. Animal hosts in Victoria avoid swimming or wading in The acute illness may lasts from a few include rats, cows and pigs. potentially contaminated waters and to days to three weeks or more, with full Asymptomatic kidney infections in carrier use appropriate personal protection recovery often taking several months. animals can lead to prolonged and when work requires such exposure Method of diagnosis sometime lifelong excretion of • protecting workers in hazardous Leptospires may be isolated from the leptospires in the urine. occupations with boots and gloves blood (days 0 to 7), CSF (days 4 to 10) during the acute illness, and from the • rodent control around human urine after 10th day. habitations • prompt treatment and isolation of infected domestic animals 118 The blue book: Guidelines for the control of infectious diseases

The Department of Primary Industries Outbreak measures can be consulted for advice on herd See Control measures, above. immunisation. Additional sources of information Control of case • Victorian Department of Primary The usual treatment is doxycycline or Industries, www.dpi.vic.gov.au, benzylpenicillin. Consult the current (03) 9296 4606 or 13 6186 version of the Therapeutic guidelines: antibiotic (Therapeutic Guidelines • WHO/FAO/OIE Collaborating Centre Limited) or seek specialist infectious for Reference and Research on disease advice. Leptospirosis, Australia and Western Pacific Region, Queensland Health, Although person to person transmission http://www.health.qld.gov.au/qhpss is rare, cases should be nursed with blood and body fluid precautions. Any articles soiled with urine should be disinfected and the patient should be advised that they may continue to excrete leptospires in the urine for a month or more after the acute infection. Control of contacts Not applicable. Control of environment The exposure history of each case should be investigated to identify and control possible sources of infection such as exposure to infected animals and potentially contaminated bodies of water. Environmental control measures may include environmental clean-ups, and draining or restricting access to potentially contaminated water bodies. The Department of Primary Industries investigates suspected animal industry sources such as dairies and piggeries, and may recommend animal vaccination or other disease control measures. The blue book: Guidelines for the control of infectious diseases 119

Listeriosis

Victorian statutory requirement Late onset neonatal listeriosis generally Public health significance Listeriosis (Group B disease) must be affects full-term babies who are usually and occurrence notified in writing within five days of healthy at birth. Listeriosis is an uncommon disease in diagnosis. The onset of symptoms in these babies humans. In Australia in 2003 the rate Laboratories are required to notify occurs several days to weeks after birth was three infections per million Listeria monocytogenes isolated from (a mean of 14 days), possibly as a result population for non-pregnancy Listeriosis food or water. of infection acquired from the mother’s cases and 4.6 infections per 100 000 genital tract during delivery or postnatally births per year for maternal-foetal Infectious agent through cross-infection. infections. L. monocytogenes is a gram-positive In non-pregnant cases listeriosis usually Although most human cases appear to bacterium belonging to the genus presents as an acute be sporadic, three large outbreaks Listeria. Of the seven recognised species meningoencephalitis or septicaemia. reported overseas have clearly it is currently the only one implicated in Focal infections such as pneumonia, established L. monocytogenes to be a human cases. endocarditis, infected prosthetic joints, food-borne pathogen. These three outbreaks in the Maritime Provinces Identification localised internal abscesses and (1981), Massachusetts (1983) and Los Clinical features granulomatous lesions in the liver and Angeles County (1985) involved a total of Listeriosis predominantly affects: other organs have been described. Symptoms may have a sudden onset. 232 cases. The overall case fatality rate • people who have Fever, severe headache, nausea and was 36%. The implicated foods were immunocompromising illnesses such vomiting can lead to prostration and coleslaw, pasteurised milk and Mexican- as leukaemia, diabetes and cancer shock. style soft cheese. • the elderly The reported case fatality rate has been Reservoir • pregnant women and their foetuses around 30% in both pregnancy and non- L. monocytogenes is widespread in the • newborn babies pregnancy related groups. environment and commonly isolated • people on immunosuppressive drugs Method of diagnosis from sewage, silage, sludge, birds, and such as prednisone or cortisone. Listeriosis is diagnosed by isolation of wild and domestic animals. It has caused Listeria monocytogenes from blood, CSF, infection in many animals and resulted in Healthy adults are usually not affected placenta, meconium, foetal abortion in sheep and cattle. The but may experience transient, mild to gastrointestinal contents and other bacteria are commonly isolated from moderate flu-like symptoms. normally sterile sites. poultry. It is a common contaminant of Infection in pregnant women may be raw food. mild and a temperature before or during Incubation period Asymptomatic vaginal carriage occurs in birth may be the only sign. However the The incubation period is mostly humans and faecal carriage of up to five infection can be transmitted to the unknown. Outbreak cases have occurred per cent in the general population has foetus through the placenta, which can 3–70 days after a single exposure to an been reported. The significance of these result in stillbirth or premature birth. implicated product. Median incubation is carriers in the epidemiology of listeriosis Babies may be severely affected with estimated to be three weeks. is unknown. conditions such as septicaemia or meningitis (early-onset neonatal listeriosis). 120 The blue book: Guidelines for the control of infectious diseases

Mode of transmission Control measures Safe foods include: The main route of transmission is oral Preventive measures • freshly prepared foods through ingestion of contaminated food. It is important to educate people in high • freshly cooked foods, to be eaten Other routes include mother to foetus via risk groups about the foods likely to be immediately the placenta or at birth. The infectious contaminated and about safe food dose is unknown. handling and storage. • hard cheeses, cheese spreads, processed cheese Period of communicability People in high risk groups for listeriosis should avoid the following • milk- freshly pasteurised and UHT Mothers of infected newborns may shed high risk foods: the infectious agent in vaginal discharges • yoghurt and urine for seven to ten days after • ready to eat seafood such as smoked • canned and pickled food. delivery. Infected individuals can shed fish and smoked mussels, oysters or the organisms in their stools for several raw seafood such as sashimi or sushi Safe food handling and storage: months. • pre-prepared or stored salads, including coleslaw and fresh fruit salad • wash your hands before preparing food Susceptibility and resistance and between handling raw and ready • drinks made from fresh fruit or Although healthy people can be infected, to eat foods the disease generally affects vulnerable vegetables where washing procedures • keep all food covered during storage groups in the community such as: are unknown (excluding canned or pasteurised juices) • place all cooked food in the refrigerator • people who have within one hour of cooking immunocompromising illnesses (such • pre-cooked meat products which are as leukaemia, diabetes, cancer) eaten without further cooking or • store raw meat, raw poultry and raw heating, such as pate, sliced deli meat fish on the lowest shelves of your • the elderly including ham, strassburg and salami refrigerator to prevent them from • pregnant women and their foetuses and cooked diced chicken (as used in dripping onto cooked and ready to eat • newborn babies sandwich shops) foods • people on immunosuppressive drugs • any unpasteurised milk or foods made • keep your refrigerator clean and the (such as prednisone or cortisone). from unpasteurised milk temperature below 5°C There is little evidence of acquired • soft serve ice creams • strictly observe use-by and best before immunity even after prolonged severe • soft cheeses, such as brie, camembert, dates on refrigerated foods infection. ricotta and feta (these are safe if • do not handle cooked foods with the cooked and served hot) same utensils (tongs, knives, cutting • ready-to-eat foods, including leftover boards) used for raw foods, unless they meats which have been refrigerated for have been thoroughly washed with hot more than one day soapy water between uses • dips and salad dressings in which • all raw vegetables, salads and fruits vegetables may have been dipped should be well washed before eating or juicing and consumed fresh • raw vegetable garnishes. The blue book: Guidelines for the control of infectious diseases 121

• defrost food by placing it on the lower Investigation/outbreak measures shelves of a refrigerator or use a • Obtain medical history from treating microwave oven doctor. • thoroughly cook all food of animal • Obtain a food history from patient. origin • Test any available suspected foods. • keep hot foods hot (above 60°C) and • Assess the possibility of common cold foods cold (at or below 5°C) source outbreaks if there is a cluster of • reheat food until the internal cases. temperature of the food reaches at • Epidemiological investigation of cases least 70°C (piping hot) should be used to detect outbreaks • reheat left overs until piping hot and to determine source. • when using a microwave oven, read • Molecular subtyping should be used to the manufacture’s instructions determine the association between carefully and observe the isolates from cases and any foods recommended standing times, to positive for L. monocytogenes. ensure the food attains an even • Investigate the source of any foods found temperature before it is eaten. to be positive for L. monocytogenes to Foods are regularly tested for the determine at what point they became presence of L. monocytogenes. contaminated. Processed, packaged ready to eat foods • Recall contaminated food if necessary. found to be contaminated with L. monocytogenes are recalled from sale. Control of case Treatment is usually with penicillin or amoxyl/ampicillin either alone or in combination with trimethoprim+ sulfamethoxazole. For penicillin sensitive patients trimethoprim+ sulfamethoxazole may be used alone (see the current edition of Therapeutic guidelines: antibiotic, Therapeutic Guidelines Limited). 122 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 123

Malaria

Victorian statutory requirement The rapidly rising temperature is thick and thin films. Repeated Malaria (Group B disease) must be commonly associated with shaking chills, examination may be necessary due to notified in writing within five days of muscle pains, back pain, nausea and variations in density of parasites. diagnosis. headache, and the episode frequently Confirmation of the species should be ends with profuse sweating. Other sought from a reference laboratory. School exclusion is not required. symptoms may include confusion or Infectious agent other neurological signs, diarrhoea, dark Incubation period The time between an infectious mosquito Malaria is caused by parasites of the urine, jaundice, cough and respiratory bite and the first detection of parasites in Plasmodium spp. Four species of distress. a blood smear is generally 6–16 days. Plasmodium (P.) can infect humans: The following severe complications may Symptoms may not occur at that time P. vivax, P. ovale, P. malariae and occur, usually with P. falciparum and the first presentation of the infection P. falciparum. Infection is most commonly infections: coma, acute encephalopathy, may be delayed for weeks or months. caused by P. vivax or P. falciparum, the cerebral oedema, vomiting, renal failure, Commonly, clinical symptoms occur after latter causing the most severe form of severe anaemia, thrombocytopenia, 7–14 days for P. falciparum, 7–30 days malaria. Mixed infections may occur. pulmonary oedema, shock, acidosis, for P. malariae and 8–14 days for P. vivax coagulation defects, respiratory failure, Identification and P. ovale. liver failure and death. Case fatality rates Clinical features in non-immune people may be 10–40%. Suboptimal suppression with The most prominent feature of malaria is prophylactic drugs may delay the clinical Atypical presentations can occur which fever. Classic descriptions of fever with a presentation and transmission by blood predominantly involve a diarrhoeal illness regular recurring pattern every two or transfusion usually results in a shorter and have resulted in delayed diagnosis three days is not usually present when the incubation period. disease begins. Irregular fever also may and death. Other infections such as the occur due to mixed infections, ineffective bacterial infection may Public health significance use of prophylactic drugs and partial occur concurrently. These should be and occurrence treatment. Patients commonly feel well on looked for, especially if the patient fails to The malaria situation worldwide is the days when fever is absent. respond well to appropriate treatment. deteriorating. There are increasing levels A presumptive diagnosis of malaria should Individuals who are partially immune or of transmission and it has returned to be made for any person with a high fever have been taking anti-malarial areas where it had previously been who has been to a malarious area until chemoprophylaxis, may show an atypical eradicated. Drug resistance has proved otherwise, particularly with recent clinical picture with wide variations in the increased and there has been a spread travel. incubation period. Malaria due to species of vector resistance to insecticides. Early diagnosis with prompt appropriate other than P. falciparum is generally not life An estimated 220 million new infections treatment is essential as malaria can be threatening except in the very young, very a year occur worldwide. The disease is a fatal disease. If the initial blood film is old and those with immunodeficiency or endemic in areas of Asia, Africa and negative for malarial parasites it should other concurrent disease. Central and South America. be repeated within 12–24 hours and Method of diagnosis preferably when the temperature is Malaria can be diagnosed by rising. One negative test does not demonstration of malaria parasites in exclude the diagnosis, particularly if the blood films. Blood samples should be patient has taken antibiotics which may sent to a laboratory with experience in result in partial treatment of the infection. the diagnosis of malaria by the use of 124 The blue book: Guidelines for the control of infectious diseases

The World Health Organization certified Period of communicability • using knock-down sprays, mosquito Australia free of endemic malaria in 1981 Infected cases may remain infectious for coils, or plug-in vaporising devices but several hundred imported cases are years if untreated or inadequately treated indoors recorded each year. However the region so that gametocytes persist. The infected • using mosquito nets, preferably pre- lying north of a line joining Townsville on mosquito remains infected for life. treated with an appropriate insect the east coast and Port Hedland on the repellent. west coast remains receptive and Susceptibility and resistance vulnerable to the re-establishment of the People traveling to malarious areas are at There is no drug that is completely safe disease. This is due to the presence of risk. and completely effective for prophylaxis known or suspected vectors, suitable against malaria. The decision to Control measures environmental conditions and the recommend chemoprophylaxis and the Preventive measures continual arrival of malaria-infected choice of drug(s) must involve an analysis Travellers should be advised of the four travellers. of the risks and benefits based on the principles of malaria protection: following considerations: Many cases occur among migrants who • be aware of the risk, the incubation become infected after re-visiting their • prevalence and type of resistance of period, and the main symptoms native country after a delay of many the malarial parasite to the available years when they may have lost their • avoid being bitten by mosquitoes, drugs immunity. In Victoria, all malarial patients especially between dusk and dawn • level of malaria transmission in recent times have provided travel • take antimalarial drugs • duration and place of stay, particularly histories which include countries with (chemoprophylaxis) to suppress in rural areas endemic malaria. Recently, the countries infection where appropriate • intensity of vector mosquito contact most commonly associated with • immediately seek diagnosis and imported malaria have been Papua New • availability of adequate health care treatment if a fever develops one week Guinea, East Timor and Indonesia. or more after entering an area where •age Reservoir there is a malaria risk. • traveller’s current health and medical Humans. Personal protection against mosquito history bites remains the first line of defence • risk of traveller not complying with Mode of transmission against malaria. Measures to recommend recommendations. A female Anopheles mosquito ingests include: gametocytes from an infected human. All prophylactic drugs should be taken The parasite must undergo 8–35 days of • avoiding outdoor exposure between with unfailing regularity for the duration development within the mosquito before dusk and dawn of the stay in the malaria risk area and the infective sporozoites are formed. The • wearing long, loose clothing after dusk, should be continued for four weeks after sporozoites are transmitted to another preferably in light colours the last possible exposure to infection as parasites may still emerge from the liver person via the bite of an infected • avoiding perfumes and colognes mosquito. and cause disease during this period. • using effective insect repellents, for The single exception is atovaquone/ The disease may also be transmitted by example products containing up to 20% proguanil, which can be stopped one blood or congenitally in untreated or DEET week after return. Over-reliance on inadequately treated cases. chemoprophylaxis is ill-advised as drug resistance by the malaria parasite continues to change. The blue book: Guidelines for the control of infectious diseases 125

Malaria poses a serious threat to If the species cannot be identified with pregnant women as it can compromise confidence, the patient should be treated foetal development, possibly resulting in as for the most serious infection with P. premature labour or miscarriage. falciparum. Although primaquine reduces Pregnant women should be advised to the risk of relapses of disease, relapses avoid travel to malarious areas if can occur. possible. Similarly, malaria presents Control of contacts considerable risks for children, Travelling companions or recipients of particularly the very young, and the any blood transfusion from the case choice of suitable drugs is limited. should be warned that they may also be Mosquito avoidance measures should be at risk of developing the disease and emphasised. should seek help promptly if suggestive There is no vaccine available. symptoms develop. Control of case Control of environment Isolation of the case is not required. Not applicable as Victoria’s ecology is Mosquito contact with the patient should unlikely to sustain endemic malaria, be prevented, especially in tropical areas although this is possible in northern of Australia where mosquitoes capable of areas of Australia. transmitting the disease are present. The country of acquisition of the measures should be determined. It is important to Any outbreaks of malaria in Australia exclude acquisition within Australia or require immediate public health from an unusual source, such as a blood interventions. transfusion, that would need further Additional sources of information investigation. • Australian Government Department of Treatment is complex and advice should Foreign Affairs and Trade, be sought from an infectious disease http://www.smartraveller.gov.au/ physician. Most strains of • Centers for Disease Control and P. falciparum today are resistant to Prevention, www.cdc.gov/travel chloroquine. Only P. falciparum contracted in some parts of China, • World Health Organization, Central America and the Middle East are International Travel and Health booklet, still sensitive to chloroquine. www.who.int/ith P. vivax, P. ovale, and P. malariae are sensitive to chloroquine but P. vivax resistant to chloroquine has been found in Irian Jaya, Myanmar, Papua New Guinea and Vanuatu. 126 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 127

Measles (rubeola)

Victorian statutory requirement • cough, coryza, conjunctivitis and Serodiagnosis is not possible between Measles (Group A disease) must be Koplik’s spots. eight days and eight weeks after measles notified immediately by telephone or fax The characteristic red, blotchy rash vaccination. Suspected measles cases followed by a written notification within appears on the third to seventh day. It who have been recently vaccinated prior five days. begins on the face before becoming to their illness onset can only be confirmed as cases if they have an School exclusion for cases and contacts generalised and generally lasts four to epidemiological link to a confirmed is: seven days. measles case or if a non-vaccine strain is • cases should be excluded for at least Complications can include otitis media, identified in a clinical specimen by four days after rash onset pneumonia and encephalitis. Sub-acute culture or molecular methods. sclerosing panencephalitis (SSPE) • immunised contacts do not need develops very rarely as a late sequela. exclusion Incubation period Persons who have been previously The incubation period is approximately • unimmunised contacts should be immunised may present with non- ten days, but varies from seven to 18 excluded until 14 days after the first classical features. days from exposure to the onset of fever. day of appearance of rash in the last It is usually 14 days until the rash case. If unimmunised contacts are Measles infection (confirmed virologically) appears. vaccinated within 72 hours of their first may rarely occur without a rash. contact with the first case or if they Method of diagnosis Public health significance receive immunoglobulin within seven The diagnosis should be confirmed by and occurrence days of the contact they may return to demonstration of anti-measles IgM The use of measles vaccine in infant school. antibody, detection of measles RNA by immunisation programs globally has led polymerase chain reaction (PCR) to a significant reduction in measles Infectious agent techniques (if available) or by viral cases and deaths. In addition to Measles virus is a member of the genus culture. The latter is particularly useful for providing direct protection to the vaccine Morbillivirus. epidemiological purposes. recipient immunisation against measles results in the indirect protection of Identification Suspected cases should be bled at the unimmunised persons () if Clinical features time of clinical diagnosis. The detection high enough coverage is achieved. Clinical features of measles include of anti-measles IgM increases to 100% for Measles vaccine has several major prodromal fever, a severe cough, samples taken 4–14 days after rash effects on measles epidemiology. These conjunctivitis, coryza and Koplik’s spots onset. If testing is negative for anti- include achieving an increase of the on the buccal mucosa. These are present measles IgM on a sample collected three mean age of infection and an increase in for three to four days prior to rash onset. days or less after rash onset, it should be the time between epidemics. The most important clinical predictors repeated between 4–14 days after rash are included in the clinical case onset. Despite the availability of an effective measles vaccine for almost 40 years the definition for measles which is an illness The diagnosis can also be confirmed by disease still causes a considerable characterised by all the following demonstration of a fourfold or greater burden in many countries. This is features: change in measles antibody titre primarily because of underutilisation of between acute and convalescent-phase • generalised maculopapular rash, the vaccine. In 2001 it was estimated sera. These should be obtained at least usually lasting three or more days, AND that there were 30 million measles cases two weeks apart, with the tests • fever (at least 38°C if measured) and 777 000 deaths. Most deaths preferably conducted in parallel at the present at the time of rash onset, AND occurred in developing countries, same laboratory. 128 The blue book: Guidelines for the control of infectious diseases

principally in Africa and Asia. Thirteen who have not been vaccinated are most Control measures countries reported that routine measles at risk along with the small numbers of Preventive measures vaccine coverage was below 50%. Large unimmunised children. Live attenuated measles vaccine is measles outbreaks continue to occur. recommended for all persons born after These occur especially in areas of Reservoir 1966 unless specific contra-indications developing countries with low vaccine Humans. to live vaccines exist. coverage and among children living in Mode of transmission It is recommended that this vaccine be countries where there are unstable social Measles transmission is airborne by given as measles-mumps-rubella (MMR) conditions. These outbreaks frequently respiratory droplet nuclei spread or it can vaccine at 12 months of age and a have high case-fatality rates. be transmitted by direct contact with second dose at four years of age (prior to In Australia, live attenuated measles infected nasal or throat secretions. The school entry). The second dose is not a vaccine was licensed in 1968 and virus can persist in the environment for booster but is designed to vaccinate the included in childhood vaccination up to two hours. Transmission has been approximately five per cent of children schedules in 1971. Even after the first reported to people whose only apparent who do not seroconvert to measles after national measles campaign in 1988, source of infection was a room the first dose of vaccine. coverage remained too low (85%) to presumably contaminated with measles Older children and adults born after 1966 achieve herd immunity. This allowed virus when it had been occupied by a who are unimmunised and those with major measles outbreaks in many areas patient with measles up to two hours serological evidence of non-immunity in 1993–94. In 1994 a second dose of earlier. should be given at least one dose of measles-mumps-rubella (MMR) vaccine MMR and ideally a second dose of MMR was introduced for a year’s cohort of Period of communicability one month later. children aged between 10 and 16 years. Cases are infectious from slightly before Although the incidence of measles the beginning of the prodromal period, A dose of MMR should also be given declined, seroprevalence studies usually five days prior to rash onset. They postpartum for non-immune women, indicated that further measles outbreaks continue to be infectious until four days followed a month later with a repeat were likely. after the onset of the rash. dose. Pregnancy should be avoided for 28 days after vaccination. In July 1998 a ‘catch-up’ campaign was Susceptibility and resistance Unimmunised health care workers, conducted to give a dose of MMR Natural infection provides lifelong including medical practice staff, born vaccine to all primary school children immunity. A history of prior measles after 1966 are at high risk of measles before lowering the recommended age infection should be confirmed infection. The measles vaccination status for the second dose of MMR vaccine to serologically before vaccination is of all health care workers measles should four years in 1999. After the measles deferred as reports of clinical measles be assessed prior to commencing work control campaign an estimated 96% of infection are not always accurate. children aged five to 12 years had and non-immune workers should be Vaccination at 12 months of age received two doses of MMR. vaccinated with two doses of MMR produces a protective antibody in vaccine. Although the endemic spread of measles approximately 95% of recipients. The has now been interrupted in Australia, second dose of vaccine, recommended small outbreaks have continued to occur at 4 years, increases protection to following importation of measles cases approximately 99% of recipients. from overseas. Adults born after 1966 The blue book: Guidelines for the control of infectious diseases 129

Control of case • determine which of the contacts are • Infants six to nine months of age There is no specific treatment for likely to be susceptible to measles (see should not be given MMR but should measles. Treatment is supportive with below). be offered immunoglobulin if within particular attention to the possible 2.Protection of susceptible contacts of a seven days from first contact with a complications of measles, particularly measles patient with: case. pneumonia and encephalitis. • MMR if within 72 hours of first contact • Infants between nine and twelve The case should be immediately isolated with the patient months of age should be offered early to minimise any possible ongoing MMR if within 72 hours of first contact transmission. If the case requires • immunoglobulin if longer than 72 hours with a case, and receive a further dose hospitalisation they should be nursed in but within seven days from contact at 12 months of age or four weeks after an isolation room, preferably with (see below); then offer MMR three the first dose, whichever is later. This negative pressure ventilation, using months later. second dose does not replace the respiratory and standard precautions. Susceptible contacts are best identified routine dose of MMR at four years but Cases not requiring hospitalisation by excluding contacts not considered to is given because children under 12 should be advised to stay at home until be at risk. These are: months have a lower likelihood of they are no longer infectious, usually the • children aged one to four years who becoming immune (seroconverting) fifth day after rash onset. Children are have documented evidence of having after measles vaccination. excluded from school or child care for at had one measles vaccine dose If contact with the infectious case least four days after the onset of the • persons born after 1966 who have had occurred between 72 hours and seven rash. two measles vaccine doses days, immunoglobulin should be offered (see below). The Department of Human Services – susceptible contacts who have actively investigates all suspected documented evidence of having had Immunoglobulin prophylaxis measles cases to confirm the diagnosis, at least one measles vaccine dose The recommended dose of identify the source of infection, identify do not require immunoglobulin but immunoglobulin is 0.2 mL/kg body other cases, and to identify and protect should be offered a second MMR weight (maximum dose = 15 mL) given susceptible contacts in the community. dose by deep intramuscular injection. Children who have immunodeficiency diseases Control of contacts • persons born before 1966, as they are such as leukaemia, lymphoma, or HIV The Department of Human Services will likely to have natural immunity trace and manage susceptible community infection require a higher dose (0.5 • persons with documented evidence of contacts of cases. The responsibility of mL/kg body weight, maximum dose = 15 immunity through vaccination or identifying and protecting susceptible mL). natural infection. contacts exposed in health care Control of environment institutions, such as medical practices or Prophylaxis for contacts under 12 Any room visited by a patient while emergency departments, is the months of age infectious should be left vacant for at responsibility of the individual institution. • Infants less than six months of age least two hours after the patient has left. should not be given MMR and should Control measures require: This includes medical consulting rooms. not be offered immunoglobulin unless Environmental clean-up is not generally 1.Identification of susceptible contacts: the mother is a case, or the mother has recommended, although items • make a list of other people who been tested and found to have no contaminated with nasal and throat attended the same area at the same measles immunity. discharges should be disposed of time or within two hours after the visit carefully. of the measles patient, including staff 130 The blue book: Guidelines for the control of infectious diseases

Outbreak measures During an outbreak, children and their Outbreaks in the community setting siblings who are aged between one and occur sporadically as a result of imported four years should receive their routine measles cases exposing local second dose of MMR early (but not less susceptible people. The epidemiology of than four weeks after their first dose). outbreaks has changed with the They are then considered to have introduction of childhood vaccination, completed their MMR vaccination with young adults now at highest risk. schedule and so do not need a further Outbreaks in schools may still occur if dose at four years of age. there are significant numbers of Child care unvaccinated students. If there is a case of measles in a child The Department of Human Services care setting where infants between six to conducts detailed investigations of twelve months of age are present, they clusters of cases. should be excluded from attendance for 14 days to interrupt local transmission: Special settings Infants can return if they receive MMR Schools vaccination (9 –12 months) within 72 Although outbreaks mainly affect hours of their first contact or if they unvaccinated children, highly vaccinated receive immunoglobulin (6–12 months) school populations have also been within seven days. affected. It is not necessary for infants under six Cases are excluded from school and months to be excluded unless the child care for at least four days after rash mother is a case, or where the mother is onset. aware she has no protective immunity. Immunised contacts are not excluded. Unimmunised contacts should be Additional sources of information excluded until 14 days after the first day • Communicable Diseases Network of appearance of the rash in the last Australia New Zealand 2000, case. Guidelines for the control of measles If unimmunised contacts are vaccinated outbreaks in Australia, Communicable within 72 hours of their first contact with Diseases Intelligence technical report the first case or if they receive series, www.cda.gov.au immunoglobulin within seven days of the contact they may return to school. The blue book: Guidelines for the control of infectious diseases 131

Melioidosis

Victorian statutory requirement Incubation period Period of communicability Notification is not required although it is Australian data suggests an incubation The disease is only very rarely recommended that cases of melioidosis period of 1–21 days. This can be transmitted person to person. with a history of travel to northern prolonged in infections which initially Australia be reported to public health become latent. Susceptibility and resistance units in the relevant state or territory. Disease in humans is uncommon even Public health significance among people in epidemic areas who School exclusion is not required. and occurrence have close contact with soil or water Infectious agent Melioidosis is endemic in South East Asia containing the infectious agent. Burkholderia pseudomallei are small and northern Australia. It is now Approximately two thirds of cases have a gram-negative, aerobic bacillus. It was recognised in the northern areas of the predisposing medical or recrudescence previously named Pseudomonas Northern Territory as the most common in asymptomatic infected individuals. pseudomallei or Whitmore’s bacillus. cause of fatal community-acquired bacteraemic pneumonia and as the most Control measures Identification common cause of severe community Preventive measures Clinical features acquired sepsis in Thailand. The There is no vaccine available. Basic Pneumonia is the most common clinical incidence of disease in Victorian hygiene can help limit the spread of presentation of melioidosis, ranging from residents is unknown. many diseases including melioidosis and measures such as wearing shoes outside a mild respiratory illness to a severe In a 10-year prospective study in the may prevent transmission. pneumonia with septicaemia, with a Northern Territory 252 cases were mortality rate often over 50%. Other identified, with a case fatality rate of 19%. Control of case presentations include skin abscesses or The majority of cases in northern A history of travel to northern Australia or ulcers, internal abscesses of the prostate, Australia occur during the wet season in tropical regions of South East Asia should kidney, spleen and liver, fulminant November to April. Disease can affect all be determined. septicaemia, and neurological illnesses ages but is more common in adults and Initial intensive antibiotic therapy usually such as brainstem encephalitis and acute predominantly occurs in males and consists of trimethoprim/ flaccid paralysis. Asymptomatic infection Australian Aboriginals. Risk factors for sulfamethoxazole with ceftazidime, can occur and in a small proportion of disease include diabetes, chronic lung meropenem, or imipenem. The these people the infection can re-activate and renal disease and excess alcohol trimethoprim/sulfamethoxazole from a latent form many years later. consumption. component is usually continued for three Method of diagnosis months to ensure eradication. Consult A definitive diagnosis of melioidosis can Reservoir the current version of Therapeutic only be made by isolation of the Burkholderia pseudomallei have been guidelines: antibiotic (Therapeutic organism from the respiratory tract, lung, found in soil and water in tropical regions Guidelines Limited). Specialist infectious blood or other sites. of northern Australia and South East disease advice should be sought for all Asia. The likelihood of a bacterial diagnosis is cases. increased by using selective culture Mode of transmission Follow-up of cases and adherence to media (modified Ashbrown’s broth), Infection is thought to be acquired eradication therapy are critical to prevent frequent sampling (sputum, throat, rectal through percutaneous inoculation, relapse, which can be fatal. and swabs) and collection of blood although inhalation and ingestion are cultures. also possible. 132 The blue book: Guidelines for the control of infectious diseases

Control of contacts Investigation of potential sources is important. Human carriers are not known. Control of environment Not applicable.

Outbreak measures Melioidosis has been identified as a potential bioterrorism agent. Any case or cases presenting without a clear history of exposure in an endemic area should be reported to the Department of Human Services for further investigation.

Additional sources of information • Currie, BJ, Fisher, DA, Howard, DM, Burrow, JNC et al. 2000, ‘Endemic melioidosis in tropical northern Australia; a ten year prospective study and review of the literature’, Clin Infect Dis, vol. 31, pp. 981–986. • Currie, BJ 2000 ‘Melioidosis: an Australian perspective of an emerging infectious disease’, Recent Adv Microbiol, vol. 8, pp. 1–75. • Currie, BJ, Fisher, DA, Howard, DM, Burrow, JNC et al. 2000, ‘The epidemiology of melioidosis in Australia and Papua New Guinea’, Acta Tropica, vol. 74, pp. 121–127. • Northern Territory Centre for Disease Control, http://www.nt.gov.au/health The blue book: Guidelines for the control of infectious diseases 133

Meningococcal disease

Victorian statutory requirement Method of diagnosis incidence in the winter and spring Suspected or confirmed meningococcal Diagnosis is usually made on clinical months. Although the reasons for this infection (Group A disease) must be grounds confirmed by laboratory tests. seasonality are not clear, there is notified immediately by telephone or fax Laboratory tests include: evidence that influenza virus or followed by a written notification within • gram stain of cerebrospinal fluid, skin pneumoniae infections may five days. lesion smear or joint fluid predispose to invasive disease and that closer personal contact or lack of School exclusion: cases should be • culture of blood, CSF or other sterile ventilation may facilitate transmission of excluded until adequate carrier site meningococci. eradication therapy has been completed. • polymerase chain reaction (PCR). Contacts do not need to be excluded if The three major serogroups of receiving carrier eradication therapy. Meningococcal isolates from all cases of meningococci cause different patterns of invasive disease should be sent to MDU disease. Serogroup A meningococci Infectious agent at the University of Melbourne to ensure cause outbreaks of infection in areas Neisseria meningitidis (the appropriate monitoring of serogroups such as the meningitis belt of Africa meningococcus) is a gram-negative and to perform susceptibility testing. This where the incidence of meningococcal diplococcus. Various serogroups have needs to be authorised by the infection rises sharply towards the end of been recognised including groups A, B, Communicable Diseases Section of the the dry season and declines rapidly with C, 29E, H, I, K, L, W135, X, Y and Z. Within Department of Human Services. the onset of rains. The epidemics occur these groups, certain serotypes have in 8–14 year cycles. Since 1990 New been identified, for example, group B Incubation period Zealand has been experiencing an serotypes 2b and 15. In 2004 groups B The incubation period is commonly three epidemic of serogroup B meningococcal and C were the most common in to four days, but can vary from two to disease. Age-standardised rates for Maori Victoria. seven days. People who do not develop and Pacific Island people were three and the disease in the seven days after six times higher respectively than for the Identification colonisation may become asymptomatic European population. Serogroup C Clinical features carriers. meningococci are usually associated Clinical features of meningococcal with sporadic disease but can cause infection include an acute onset of Public health significance small or large outbreaks. Attack rates for meningitis or septicaemia. Typical and occurrence serogroup C are between those seen features of these include fever, intense Invasive meningococcal infections occur with serogroups A and B. headache, nausea, vomiting and neck in endemic and epidemic forms. In stiffness. There may be a petechial or Australia epidemic disease has not Meningococcal disease has had cyclical purpuric rash on the trunk and limbs occurred for many years. Endemic peaks of incidence. Notification of that may sometimes cover large areas of disease is at low levels of incidence and ‘meningitis’ reached a peak of 33.1 cases the body. In fulminating cases there is cases are generally unrelated to each per 100 000 in 1942 (2371 cases) as part sudden prostration and shock other. Despite this, invasive of a pandemic of serogroup A disease associated with the characteristic rash meningococcal disease is of public during World War II. Apart from another and this condition has a high fatality health importance and is frequently a peak of activity in the early 1950s, there rate. Chronic meningococcal cause of public alarm and receives a high was a steady decline of notifications to septicaemia can also occur with febrile level of media attention. less than 0.5 cases per 100 000 in 1987. The notification rate for meningococcal episodes, skin and fleeting joint Meningococcal disease characteristically disease to the National Notifiable pains. has a seasonal pattern with a peak of Diseases Surveillance System (NNDSS) 134 The blue book: Guidelines for the control of infectious diseases

has been slowly increasing over the past Period of communicability There is no evidence to suggest carriers 10 years from 1.6 per 100 000 in 1991 to It is communicable until the organisms will suddenly become cases after weeks 3.1 per 100 000 in 2000. In 2002 there are no longer present in discharges from or months of carriage. were 129 notifications in Victoria (1/3 of the nose and mouth. Conjugate vaccines are available that the national total) of which 47 were can give long lasting protection against Susceptibility and resistance serogroup B and 72 were serogroup C. meningococcal serogroup C disease. Susceptibility to clinical disease is low as There is no vaccine for meningococcal Reservoir evidenced by the usual high ratio of serogroup B disease. There is Human. carriers to cases. Susceptibility polysaccharide quadrivalent vaccine decreases with age although a available in Australia against groups A, C, Mode of transmission secondary peak of meningococcal Y and W135 however it cannot be given Respiratory droplets shed from the upper meningitis occurs in adolescents and under two years of age and only protects respiratory tract transmit meningococci young adults in the age group of 15–24 for one to five years. This vaccine is from one person to another. Humans are years. Patients deficient in certain considered a ‘travel’ vaccine for travellers the only natural hosts for meningococci complement components in the blood to epidemic and highly endemic areas and the organism dies quickly outside are prone to recurrent meningococcal such as Brazil, Mongolia, Vietnam, India, the human host. It is not able to be infections. There is an increased and Nepal and sub-Saharan Africa and is a isolated from environmental surfaces or prolonged risk of secondary infections in requirement for visits to Mecca. samples. close contacts. In one series, the Salivary contact has in the past been incidence of such infection was 0.5% There are different brands of (conjugate) regarded as a means of transmission of with a median interval of seven weeks meningococcal serogroup C vaccine meningococci. There is little evidence to between the index and secondary cases. available. The vaccines contain support this view. Available evidence Secondary cases have been reported up meningococcal serogroup C ‘sugars’ indicates that neither saliva nor salivary to five months later. The risk in joined with an inactive protein of either contact is important in the transmission household contacts is 500 to 800 times diphtheria or tetanus toxoid and additives of meningococci. Saliva has been shown higher than in the general population. aluminium phosphate or hydroxide. to inhibit the growth of meningococci. There is no maternal immunity. Under the National Immunisation Carriage of meningococci has not been Program, a single dose of meningococcal convincingly shown to be associated with Control measures serogroup C vaccine is given at 12 saliva contact. A case-control study of Preventive measures months of age. If parents wish to United Kingdom university students Note that most strains of meningococci purchase vaccine to immunise their child found no association between carriage of do not cause disease, but instead prior to 12 months of age, infants from six meningococci and sharing of drinks or provide protection. Other protective weeks to four months of age at the cigarettes and a weak association with bacteria such as Lactamicas (Neisseria commencement of vaccination receive ‘intimate kissing’ (OR = 1.4 & 95% CI, lactamica spp) also colonise the three doses one to two months apart. 1.0–1.8%). nasopharynx. By giving Babies from four months to 11 months at It is unclear whether carriage in these chemoprophylaxis when it is not needed the commencement of vaccination circumstances is due to saliva contact these bacteria, which are protective, are receive two doses one to two months rather than to droplets shed during also eradicated. People can carry apart. household-like (close and prolonged) meningococci with no ill effects for many contact. months. Carriage produces protection. The blue book: Guidelines for the control of infectious diseases 135

The National Meningococcal C Clearance antibiotics should only be Clearance antibiotics should only be Vaccination Program is a four year given to the following people (see below) given to those people who are at risk of program from 2003–2006 in which all who have had contact with the case either being the source of disease in the persons aged 1–19 years in 2003 are seven days prior to the onset of the case, or of having acquired the invading eligible for a dose of meningococcal C case’s illness. They should be organism from the case. The aim of vaccine. commenced as soon as possible after clearance antibiotics is to prevent further Control of case diagnosis. transmission. Prompt treatment with parenteral Contacts include: There are three antibiotics currently used penicillin in adequate doses should begin • household contacts are defined as for the chemoprophylaxis of when a presumptive clinical diagnosis is those people living in the same house meningococcal disease. Each agent has made prior to laboratory confirmation. In and include recent visitors who stayed advantages and disadvantages and each cases with a very acute onset, such overnight in the seven days preceding is the preferred agent in specific treatment should commence prior to the onset of the case’s illness circumstances. transfer of the patient to hospital even • dormitory contacts in boarding Clearance antibiotic for contacts of though there may be some interference meningococcal disease: with laboratory confirmation by culture. schools, military barracks, school camps, and hostels in the seven days Rifampicin can be dispensed for Suitable alternatives for patients who are meningococcal prophylaxis as syrup for allergic to penicillin include ceftriaxone, preceding the onset of the case’s illness children or in capsules for older children cefotaxime or chloramphenicol. and adults. The product information Since penicillin only temporarily • sexual (intimate) contacts should be consulted for the adverse suppresses but does not eradicate the • medical, nursing, or paramedical events and side effects of rifampicin, organisms in the nasopharynx, all staff that have performed mouth-to- although it should be noted that the patients should be treated with a drug mouth resuscitation or intubation or product information recommends a such as rifampicin prior to discharge from suction or similar intimate treatment once-daily four-day regimen of rifampicin hospital. If ceftriaxone is used in with a case of meningococcal disease for the chemoprophylaxis of treatment rifampicin need not be given. prior to being started on therapeutic meningococcal disease. The two-day Consult the current version of antibiotics. regimen (below) is recommended by the Therapeutic guidelines: antibiotic The risk of meningococcal disease in Communicable Diseases Network (Therapeutic Guidelines Limited). close contacts, whilst higher than the Australia. Control of contacts general population, is still very low. The Age Dose Meningococci are likely to have been risk is highest in the first seven days after 0–2 months 1 mL syrup* Twice daily acquired from an asymptomatic person a case and falls rapidly during the for 2 days (carrier) who either lives in the same following weeks. If antibiotic prophylaxis 3–11 months 2 mL syrup* household or is a sexual partner of the is not given, the absolute risk to an 1–5 years 7.5 mL syrup* sick person. Children tend to acquire individual in the same household one to their disease from adults (in their 30 days after an index case is about one 6–12 years 300 mg capsule household) whereas teenagers and in 300. The increased risk in household > 12 years 600 mg capsule members may be due to a combination adults are more likely to acquire their *Rifampicin syrup contains 100 mg/5 mL disease from close friends. of genetic susceptibility in the family, increased exposure to virulent meningococci and environmental factors. 136 The blue book: Guidelines for the control of infectious diseases

Ciprofloxacin: Adults 500 mg orally, Clusters of invasive meningococcal single dose (minimum age 12 years and disease in people who have had a low weight >40 kg). This is preferred in level of salivary contact like footballers women taking the oral contraceptive pill. who have shared drink bottles or Although ciprofloxacin is not registered churchgoers who have shared a for chemoprophylaxis of meningococcal communion cup appear to be very rare. disease in Australia the Communicable Although clusters have been described, Diseases Network Australia recommends for example, in association with sporting it for that purpose. events and sports clubs, the reported Ceftriaxone: Adults 250 mg IM details indicate that point-source salivary (recommended for pregnant contacts). transmission was not involved. This may be dissolved in lignocaine 1% Secondary cases in situations where solution to reduce pain at the injection dribbling of saliva is common such as site. Dosage for children (<12yrs) is 125 child day-care centres are also rare. mg IM. Not for infants under 1 month of Additional sources of information age. • Australian Government Department of Control of environment Health and Ageing 2003, ‘Annual Respiratory isolation is recommended for report of the Australian Meningococcal 24 hours after commencing treatment. Surveillance Programme’, There should be concurrent disinfection Communicable Diseases Intelligence, of discharges from nose or throat and vol. 27, no. 2. articles soiled with such discharges. • Communicable Diseases Network Articles used by the patient should be Australia 2001, Guidelines for the early terminally cleaned. clinical and public health management Outbreak measures of meningococcal disease in Australia. When there are two or more cases in four • Public Health Laboratory Service 2002, weeks of exactly the same strain in a Meningococcus forum: Guidelines for childcare centre, school or university, all public health management of students and staff in the same class or in meningococcal disease in the UK, the same group as the case will be given http://www.hpa.org.uk/infections clearance antibiotics. If serogroup C • Victorian Department of Human disease is identified a vaccination Services, Advice for medical practitioners, campaign may be instituted. http://www.health.vic.gov.au/ideas The blue book: Guidelines for the control of infectious diseases 137

Molluscum contagiosum

Victorian statutory requirement Public health significance Control of case Notification and school exclusion are not and occurrence Isolation of case is not required. Infected required. Molluscum contagiosum infection occurs children should either avoid contact worldwide. Surveys in other countries sports or ensure lesions are adequately Infectious agent suggest peak incidence occurs during covered during play. No school exclusion Molluscipoxvirus is a member of the pox childhood. is required. virus (Poxviridae) family. Lesions typically resolve without Transmission through warm water is only Identification complication. Molluscum contagiosum very rarely observed. The risk of Clinical features may be more severe and more persistent transmission through public swimming This is a viral disease of the skin that in immunosuppressed patients and pool contact is very low and exclusion is produces firm, smooth, spherical, pearly particularly in patients with HIV/AIDS. rarely if ever necessary. white papules with a central dimple. Many treatments are cited in the Reservoir Most papules are 2–5 mm in diameter, literature with destruction of the lesions Humans. although papules may coalesce to form as their common goal but there is larger lesions. Mode of transmission minimal evidence to support them. Lesions in adults are more common on Molluscum is transmitted by direct Watchful waiting may still be the best the lower abdomen, genitalia or inner contact, fomites or sexual contact. option for many patients. Phenol ablation thighs. In children lesions are more Autoinoculation through scratching is may produce significant scarring. Other common on the face, trunk, and limbs. also suspected. topical preparations are under Lesions may disseminate more widely in investigation. patients with HIV infection. Period of communicability Control of contacts The period of communicability is Molluscum contagiosum may persist for Not required. unknown but probably as long as the six months to two years without lesions persist. Control of environment treatment. Lesions may resolve Not required. spontaneously or possibly as a result of Susceptibility and resistance inflammatory responses secondary to Any age may be affected although Outbreak measures bacterial infection or trauma. infection is more common in children. Consider suspending direct contact and sporting activities. Method of diagnosis Infection is more common and more The virus has not yet been cultivated. severe in the immunosuppressed. Additional sources of information Diagnosis can be confirmed by It is unknown whether prior infection • Australian College of Dermatologists, microscopy (the core of the lesion is confers any protection against http://www.dermcoll.asn.au/ expressed onto a slide then stained), by subsequent exposures. histology or by visualisation of the vesicle fluid by electron microscopy. Control measures Preventive measures Incubation period Avoid close contact with the lesions of The incubation period is unknown. affected persons. Avoid sharing baths Clinical reports suggest a range from and spas with patients with lesions, and seven days to six months. do not share face or bath towels. Molluscum contagiosum information sheet

What is molluscum Can it become a serious Further information contagiosum? disease? • Your local doctor It is a viral disease caused by the Bacterial infections can complicate • Better Health Channel molluscum contagiosum virus (MCV). molluscum contagiosum, causing the http://www.betterhealth.vic.gov.au lumps to become red and sore. However, How is it transmitted? these symptoms may also be signs that • Melbourne Sexual Health Centre It is transmitted by skin-to-skin contact, the lumps are about to disappear http://www.mshc.org.au which is usually sexual in adults and non- naturally. If symptoms don’t resolve • Victorian Department of Human sexual in children. Towels and other quickly, consult your doctor in case you Services, 1300 651 160 objects might transmit occasional cases. need antibiotic treatment. Spots appear one week to six months (usually two to three months) after How is it treated? contact. Although molluscum contagiosum eventually resolves, freezing the lumps Signs and symptoms with liquid nitrogen can shorten the Molluscum contagiosum may cause a duration of symptoms. variable number of skin lumps, A single treatment is all that is usually sometimes even ten or twenty. The required. However, it may take a couple lumps may be located on or around the of weeks for the lumps to disappear. genitals. This includes the pubic area, the inner thighs and the abdomen. They are Imiquimod cream 0.1% applied three painless, but may be slightly itchy and times daily is also effective. often pearly white in appearance with a Do not scratch any irritated areas after tiny central indentation. treatment, as this may spread the Molluscum contagiosum can be infection. If no treatment is provided it is mistaken for genital or . If a mild, self-limiting disease. It can persist you think you have molluscum for six months to two years. However, contagiosum, it is recommended that any one lump will usually clear up in two you see your doctor or other experienced to three months. health professional.

Department of Human Services The blue book: Guidelines for the control of infectious diseases 139

Mumps

Victorian statutory requirement Method of diagnosis Period of communicability Mumps (Group B disease) must be The predictive value of parotitis in the Mumps is communicable from six to notified in writing within five days of diagnosis of mumps is reduced in seven days before to nine days after the diagnosis. countries with high immunisation rates onset of parotitis. Asymptomatic and such as Australia. The diagnosis should School exclusion: exclude for nine days inapparent cases can also be infectious. be confirmed serologically by the or until swelling goes down, whichever is detection of mumps specific IgM Susceptibility and resistance sooner. antibody, or a significant rise in mumps Immunity is generally life long and Infectious agent IgG antibody in acute and convalescent develops after either inapparent or Mumps virus is a member of the family sera. Mumps virus can also be cultured clinical infections. Individuals born prior Paramyxoviridae. from swabs of the buccal mucosa and to 1970 have a high likelihood of natural from urine. immunity even if they have had no Identification history of clinical infection. Clinical features Incubation period Mumps is an acute febrile disease The incubation period ranges from 14 to Control measures characterised by swelling and tenderness 25 days. It is commonly 15–18 days. Preventive measures of one or more of the salivary glands, Live attenuated mumps vaccine is Public health significance usually the parotid and occasionally the available combined with rubella and and occurrence sublingual or submaxillary glands. measles vaccine (MMR). Vaccination Occurrence is worldwide. There is Respiratory symptoms can occur, with this vaccine results in generalised spread of the infection in particularly in children under five years. seroconversion to all three viruses in communities with low immunisation Epididymo-orchitis occurs in up to a third over 95% of recipients. Since the MMR rates; serologic studies show 85% or of postpuberal males and is most vaccine viruses are not transmissible, more of individuals in these communities commonly unilateral: sterility is an there is no risk of infection originating have evidence of previous mumps uncommon complication. Oophoritis from vaccines. infection by adult life. High childhood occurs in up to 31% of females aged over MMR vaccination is recommended for all immunisation rates in Australia have 15 years and may cause lower abdominal children at 12 months of age, unless resulted in a dramatic reduction in rates or back pain. Many infections in children specific contra-indications to the vaccine of mumps infection. Unimmunised less than two years of age are exist. A second dose is recommended at children and adults, especially males, are subclinical. Mumps meningitis is a fairly four years of age, prior to school entry. the groups at highest risk of infection. common complication. It usually occurs Control of case two to ten days after the onset of Reservoir There is no specific treatment. Cases parotitis and is self-limited with Humans. requiring hospitalisation should be symptoms lasting three to five days. nursed in an isolation room using Mumps very rarely causes sensorineural Mode of transmission respiratory precautions until nine days deafness, encephalitis and pancreatitis. Transmission occurs through via after the onset of glandular swelling. respiratory aerosols and respiratory Mumps during the first trimester may Exclude cases from school, child care or droplet spread or by direct contact with increase the risk of spontaneous abortion workplace until nine days after the onset contaminated saliva. but there is no evidence that mumps of glandular swelling. Advise parents to during pregnancy results in congenital keep the child away from other children malformations. and susceptible adults for the period of exclusion. 140 The blue book: Guidelines for the control of infectious diseases

Control of contacts Susceptible contacts should be offered immunisation with MMR vaccine. Immunoglobulin is not effective in preventing mumps. Contact isolation is not required. Control of environment Concurrent disinfection of articles soiled with nose and throat secretions.

Outbreak measures Susceptible persons should be immunised, especially those at risk of exposure. Those who are not certain of their immunity can be vaccinated if no specific contra-indications to live vaccines exist. The blue book: Guidelines for the control of infectious diseases 141

Murray Valley encephalitis virus

Arboviruses are viruses which are spread confusion, fitting, weakness or ataxia viruses. This is only accepted as by the bite of arthropods, particularly indicate the onset of encephalitis. laboratory evidence for encephalitic mosquitoes. They are divided into Method of diagnosis illnesses. alphaviruses and flaviviruses. Infection is confirmed by a significant Confirmation of the laboratory result by a Victorian statutory requirement rise in antibody titre to the virus in two second arbovirus reference laboratory is Murray Valley encephalitis (Group A blood specimens taken seven to ten days required if the case occurs in areas of disease) must be notified immediately by apart. Sera for diagnosis should be sent Australia not known to have established telephone or fax followed by written to the Director of Virology, Victorian enzootic, endemic or regular epidemic notification within five days. Infectious Diseases Reference activity. Laboratory (VIDRL), preceded by School exclusion is not required. Clinical evidence telephone contact via the Royal Clinical evidence may be present as non- Infectious agent Melbourne Hospital on (03) 9342 7000 encephalitic illness, encephalitic illness Murray Valley encephalitis virus is a advising the on-call Virologist that sera or asymptomatic disease. has been sent for urgent testing. flavivirus. It has the capacity to cause Non-encephalitic illness severe human disease, with encephalitis A diagnosis of MVEV encephalitis should Acute febrile illness with headache, being the most notable clinical feature. be considered in any patient who myalgia and/or rash Murray Valley encephalitis virus (MVEV) presents with encephalitis and who has been in the Murray Valley area within the Encephalitic disease was first isolated from patients who died Acute febrile meningoencephalitis from encephalitis in the Murray Valley in incubation period of the disease, especially in the period between characterised by one or more of the Victoria and South Australia in 1951. It following: was previously included as one of the November and March. The disease may • focal neurological disease or clearly causative agents in the disease called also be acquired at any time in northern impaired level of consciousness Australian encephalitis, which also parts of Australia or Papua New Guinea. included disease caused by Kunjin virus, Laboratory evidence requires one of the • an abnormal CT, MRI scan or EEG another flavivirus. These viruses are now following: • presence of pleocytosis in the CSF. accepted as causing two separate • isolation of MVEV from clinical material diseases. Incubation period • detection of MVEV RNA in clinical The incubation period is usually 7–28 Identification material days. Clinical features • IgG seroconversion or a significant The MVE virus commonly infects humans increase in antibody level or a fourfold Public health significance without producing apparent disease rise in titre of MVEV specific IgG and occurrence (subclinical infection). It may also cause proven by neutralisation or another Serological studies show that only one a comparatively mild disease with specific test person in about every 800 of those features such as fever, headache, nausea infected with MVE virus develops clinical • MVEV-specific IgM detected in the and vomiting. In a small percentage of all disease. Of those presenting with CSF in the absence of IgM to Kunjin, people infected, mild disease may be a encephalitis in Victoria in the 1974 Japanese encephalitis or dengue prodrome to disease progression and epidemic, approximately one-third died, viruses involvement of the central nervous one-third were left with residual brain system. This can result in meningitis or • MVEV-specific IgM detected in serum damage and one-third recovered encephalitis of variable severity. Signs of in the absence of IgM to Kunjin, completely. brain dysfunction such as drowsiness, Japanese encephalitis or dengue 142 The blue book: Guidelines for the control of infectious diseases

MVE virus is endemic in northern Reservoir The patient with suspected infection or Australia and Papua New Guinea where The primary hosts in Victoria of MVE friend or relative, should be asked to sporadic cases or small outbreaks of virus during years of high virus activity recall if in the month prior to onset of MVE virus encephalitis occur every few are water birds. Ardeiformes (herons), symptoms he or she had: years. This is usually at the end of the particularly the Rufous night-heron and • been bitten by mosquitoes wet season. Seven outbreaks of MVE the Pelicaniformes (cormorants/ • visited regions where arboviruses are virus encephalitis have occurred at darters) are the most commonly endemic irregular intervals in southeastern infected. Australia since 1917. The last of these • participated in recreational or other was in 1974. During these times there Mode of transmission activities involving exposure to was heavy rainfall leading to widespread The primary mosquito vector during bushland or other mosquito habitat flooding which promoted large increases epidemics is Culex annulirostris. Other such as gardening, bushwalking, in water bird and vector mosquito mosquitoes such as Culex australicus camping and picnicking. and some Aedes and Ochlerotatus populations. The MVE virus numbers Control of contacts species may be involved in other aspects were amplified in the bird-mosquito-bird Not applicable. cycle and humans became infected of MVE virus ecology. Control of environment when bitten by mosquitoes carrying the Period of communicability To reduce or prevent virus transmission, virus. There is no evidence of person to person interruption of human-mosquito contact MVE virus encephalitis seems to occur in transmission. is required by: people who receive large numbers of • suppression of the vector mosquito mosquito bites during a single exposure. Susceptibility and resistance population There are two theories as to how the Infection with MVE virus confers lifelong MVE virus appears and causes outbreaks immunity. • avoidance of vector contact at biting of MVE virus encephalitis in southeastern times at dusk and dawn Control measures Australia; both may be correct. The first • applying mosquito control measures in Preventive measures one postulates that the virus is carried local municipalities from northern parts of Australia by birds Patients can be managed at any hospital, • using personal protection measures migrating south in search of food after but facilities for providing intensive care such as long sleeves, long trousers and heavy rainfall down the southeastern and artificial respiration must be mosquito repellents parts of the continent. This occurs in available. There is no preventative repeated mosquito-bird-mosquito vaccine available. • avoiding mosquito-prone areas. amplification cycles. The other suggests Control of case that the virus persists during inter- Investigate the source of infection. epidemic periods in cryptic foci along the Search for unreported or undiagnosed Murray River and the MVE virus only cases of encephalitis from the Murray- amplifies and becomes evident when Darling drainage basin. weather conditions are conducive to massive local mosquito and bird multiplication. The blue book: Guidelines for the control of infectious diseases 143

Outbreak measures Following notification of a seroconversion to MVE virus or information of human notification: • an emergency meeting of the Victorian Arbovirus Task Force (VATF) will be convened by the Department of Human Services • the presence of MVE virus in the area will be notified to relevant regional offices and local health council personnel • suitable media releases will be made available • appropriate VATF members will visit the area to consult and advise local councils, health and tourism authorities • depending on the actual or potential severity of the epidemic, meetings of relevant personnel will be arranged in the affected area to consider control measures.

Additional sources of information Victorian Department of Human Services, Victorian Arbovirus Task Force contingency plan for outbreaks of MVE. 144 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 145

Mycobacterial infections (non-tuberculosis)

Victorian statutory requirement Clinicians who suspect infection with Reservoir Notification and school exclusion are not atypical mycobacteria should liaise with Mycobacteria are ubiquitous in the required. a pathology laboratory to ensure that environment, including many that are clinical specimens are appropriately non-pathogenic to humans. Infectious agent collected and transported. Mycobacteria have been cultured from Mycobacterial agents include To establish a definite diagnosis of various environmental sources including M. avium-intracellulare complex (MAC), atypical mycobacterial infection, ground waters, dust and soil. The M. kansasii, M. scrofulaceum, organisms must be cultured from a case environmental niches of many others M. fortuitum, M. marinum and with clinically compatible disease. remain unknown. M. chelonae. Identification of acid-fast bacilli by direct Mode of transmission For infections due to M. ulcerans see smear on at least two occasions is highly The mode of transmission can rarely be separate chapter. suggestive of a mycobacterial infection. determined for individual cases. Atypical Histological examination of biopsies of Identification mycobacteria are probably transmitted clinical lesions may also assist in the Clinical features by aerosol from soil, dust or water, by diagnosis. Recent advances in gene MAC and M. kansasii are rare causes of ingestion, or in probes and nucleic acid amplification lung disease in humans, and mainly M. marinum and infections by skin procedures such as polymerase chain affect middle-aged and elderly persons inoculation. reaction (PCR) have allowed more rapid with underlying chronic lung conditions. diagnosis of mycobacterial infections Person to person spread of atypical Disseminated MAC infection frequently such as DNA probes for MAC and M. mycobacteria is rare except in people occurs in people with advanced HIV kansasii. who are immunosuppressed. infection, but is rare in M. avium-intracellulare causes disease in immunocompetent hosts. Incubation period poultry and pigs but animal to human Cervical and submandibular The incubation period of atypical transmission is rare. lymphadenitis due to MAC, mycobacterial infections can rarely be M. scrofulaceum and M. kansasii may determined, but is probably weeks to Period of communicability occur in otherwise healthy young several months. Communicability of human cases is children. usually not a practical concern except in Public health significance cases of co-existing HIV infection. M. fortuitum and M. chelonae cause skin and occurrence Localised foci of disease due to some and wound infections and abscesses. Disease due to atypical mycobacterial atypical mycobacteria suggest that an They are frequently associated with infection is relatively rare. Cases of established environmental focus of trauma or surgery. M. kansasii lung infection have occurred in organisms may remain the source of M. marinum causes ‘swimming pool western Victoria in recent years. Infection infections for years. granuloma’, a nodular lesion that may with M. marinum is associated with ulcerate and is usually located on an contact with swimming pools, aquariums Susceptibility and resistance extremity. and other bodies of water. With the exception of M. marinum infections, atypical mycobacterial Method of diagnosis Atypical mycobacteria may colonise and infections (in particular MAC) are more Persons with immunodeficiencies or infect persons without causing clinical common in patients who are tissue damage such as skin trauma and disease. Skin tests to tuberculin and immunocompromised or in those with pulmonary disease may be at increased other mycobacterial derivatives may be chronic respiratory disease. risk of atypical mycobacterial infection. positive in such people. 146 The blue book: Guidelines for the control of infectious diseases

Control measures Preventive measures As little information is known about their mode of transmission, prevention of atypical mycobacterial infections is difficult. Environmental contamination of skin lesions may be reduced by some measures, including the wearing of gloves and thorough hand washing when cleaning aquarium equipment (for M. marinum). Early medical advice should be sought in the event of skin lesions that do not heal. Control of case Cases of atypical mycobacterial infection usually require specialist management. Skin lesions and childhood lymphadenopathy are usually cured by surgery, sometimes in combination with anti-mycobacterial drugs. Disseminated and pulmonary infections are treated with combinations of anti- mycobacterial drugs. The clinical outcome is strongly influenced by the underlying health of the host. Control of contacts No specific measures are needed for contacts of cases. Control of environment If infections can be linked with a specific environmental source it may be possible to modify the environment or practices to minimise further transmission.

Outbreak measures Not applicable. The blue book: Guidelines for the control of infectious diseases 147

Mycobacterial infections (tuberculosis)

Victorian statutory requirement positive tuberculin reactions, and those Incubation period Tuberculosis (Group B disease) must be with a history of inadequately treated Infection to the primary lesion or notified in writing within five days of active tuberculosis. Positive tuberculin significant tuberculin reaction is about diagnosis including clinical suspicion. reactors with inactive tuberculosis on four to twelve weeks. chest X-ray without a previous diagnosis School exclusion: exclude until receipt of of active tuberculosis remain at some risk. Public health significance a medical certificate from the treating The risk of developing the disease is and occurrence physician stating that the child is not highest in children under three years of Tuberculosis occurs worldwide and had considered to be infectious. age, lowest in later childhood, but rises been decreasing steadily over past Contacts are not excluded. again for adolescents, young adults and decades in developed countries. This the very old. pattern was reversed with the arrival of Infectious agent HIV and increased mobility of the world’s Method of diagnosis Mycobacterium tuberculosis (human population. Tuberculosis in the USA was TB is diagnosed by a consideration of the tuberculosis) and Mycobacterium bovis on the increase in the early 1990s. (cattle tuberculosis) are the infective following: A combination of factors is thought to be agents. • clinical presentation responsible for this increase including Identification • tuberculin skin test using the Mantoux the high rate of HIV infection, Clinical features procedure overcrowding, limited health care Tuberculosis (TB) is an acute or chronic • radiographic examination, sometimes resources and falling living standards. In infection caused by the tubercle bacillus including CT scans the USA, large outbreaks of TB have Mycobacterium tuberculosis, and rarely occurred in institutions, particularly • bacteriology, direct staining and culture by M. bovis or M. africanum. The initial prisons and hospitals. These outbreaks of sputum or other specimens for the pulmonary infection usually goes have predominantly affected HIV-infected presence of M. tuberculosis unnoticed with lesions healing, persons. The increasing trend in the US sometimes leaving traces of calcified • molecular amplification (PCR) and has now been reversed and the scar tissue. The infection may however gene probes assist in rapid diagnosis. incidence rate is once again declining. progress to pulmonary tuberculosis, or Definitive diagnosis of TB rests on The World Health Organization (WHO) through blood or lymphatic spread isolation of M. tuberculosis (or estimated that a third of the world’s produce miliary, meningeal or other M. bovis) from sputum, urine, biopsy population is infected and tuberculosis extrapulmonary involvement. material, CSF or other clinical specimens. accounts for three million deaths Common symptoms include: A negative sputum test does not rule out annually. One-fifth of all deaths in adults a diagnosis of TB. Recovery and • a chronic cough sometimes in developing countries relate to TB. Two- identification of mycobacteria from accompanied by haemoptysis thirds of the world’s tuberculosis-infected specimens has become more rapid with people reside in Asia and this will have a • fevers and night sweats test procedures such as liquid medium significant impact on the control of TB in • loss of weight systems and DNA probes. Further Australia as a result of increased information on these tests can be • feeling generally unwell. immigration. obtained from the Mycobacterium Clinical suspicion of active disease should Reference Laboratory at Victorian be high in those who have a newly Infectious Diseases Reference positive tuberculin reaction, juveniles with Laboratory. 148 The blue book: Guidelines for the control of infectious diseases

Notified cases of TB in Victoria have Period of communicability The disease does not always confer dropped dramatically from 1000 cases in In theory, the patient is infectious as long protective immunity as reinfection can 1954 to 292 in 2000. However, the rate as viable bacilli are being discharged occur. of decline in the incidence of TB has from the sputum. In practice, the reached a plateau with an average greatest risk of transmitting infection is in Control measures incidence rate of 6.2/100 000 over the the period prior to diagnosis of an open Preventive measures last five years (range 5.1/100 000 in case. A sputum smear positive case is BCG vaccination has limited application 1998 to 7.0/100 000 in 1999). more infectious than a case only positive in developed countries where the incidence of TB is low. It is an effective The proportion of notified cases that on culture. The risk of transmitting the vaccine in reducing TB meningitis and were overseas-born has also increased infection is significantly reduced within death in babies and children less than from 37% in 1970 to 86% in 2000. In days to two weeks after commencing five years in countries of high TB Victoria the highest country-specific appropriate chemotherapy. prevalence. It is not recommended for incidence rates are in the Vietnamese, Susceptibility and resistance general use in the Australian community Indian, Filipino and African born Everyone is susceptible to infection, but should be considered for specific populations. This reflects the pattern of however some groups are more high risk groups such as infants and disease in their countries of birth. Of the susceptible to infection and progression young children travelling for extended overseas-born patients, almost 50% to active disease than others. Special periods to countries with a high present with disease within five years groups at risk are: incidence of TB. (Refer to The Australian and 30% present within two years of their immunisation handbook, National Health arrival in Australia. • recent immigrants and refugees from and Medical Research Council). countries with a high incidence of Reservoir tuberculosis including Vietnam, India, Control of case Humans are the primary reservoir. China, Africa and the Philippines With the introduction of potent anti-TB Diseased cattle rarely act as reservoirs. drugs, hospitalisation of tuberculosis • those in close contact with a case of patients is no longer mandatory unless active TB Mode of transmission social conditions or coexisting medical TB is transmitted mainly by inhalation of • Aboriginal people and Torres Strait conditions dictate otherwise. infectious droplets produced by persons Islanders in some parts of Australia Patients with pulmonary TB should be with pulmonary or laryngeal tuberculosis • immunosuppressed patients isolated either at home or in hospital until during coughing, laughing, shouting or • those with HIV infection and AIDS they have been on adequate anti-TB sneezing. • the elderly therapy for 14 days and sputum smears Invasion may occur through mucous are negative. Appropriate education and membranes or damaged skin. • diabetics counseling about minimising the risk of Extrapulmonary tuberculosis, other than • drug and alcohol-dependent people transmission of infection should be laryngeal infection, is generally not • people living in substandard, provided to all patients, particularly those communicable. Urine is infectious in overcrowded conditions with pulmonary TB. There is no restriction cases of renal tuberculosis. Bovine on the movement of patients with non- • institutionalised people including tuberculosis results mainly from pulmonary disease. prisoners ingestion of unpasteurised milk and dairy products. Aerosol transmission has been • health professionals. reported among abattoir workers. The blue book: Guidelines for the control of infectious diseases 149

Written notification of tuberculosis is Control of contacts – Chest X-rays may be considered on required within five days of diagnosis. Exclusion of contacts is not necessary, an individual basis. On receipt of a notification, a public unless they have signs and symptoms • Positive reactors health nurse is allocated to the patient consistent with pulmonary TB. – Initial positive reactors should be to provide support, assist with treatment Contact tracing and surveillance are the compliance and to assess the evaluated to exclude active disease. responsibility of the Department of The positive tuberculin test may requirements and extent of contact Human Services and are managed by the tracing. signify recent tuberculin conversion TB Program. Anyone identified by health or an incidental finding. Adequate anti-TB chemotherapy for an care workers as a contact of a case of TB appropriate period of time will result in should be referred to the TB Program. – Contacts identified by the TB Program as requiring further almost 100% cure rate. Short treatment Contact investigation consists of: regimens have been in use for some assessment are referred to specialist years. These involve the use initially of • history taking physicians for exclusion of active three or four drugs (isoniazid [INH], • tuberculin testing disease or consideration for treatment of latent infection. rifampicin, pyrazinamide and may include • radiographic examination. ethambutol) for two months, and – When X-ray and physical The extent of investigation is governed by continuing with isoniazid and rifampicin examination are normal, contacts the characteristics of the source case. for a further four months. Where there is with positive reaction may be offered The scope of investigation is extended evidence of drug resistance to isoniazid isoniazid treatment of latent when the following factors in the source or rifampicin or to both, short course infection, given once daily at a case are present: anti-TB chemotherapy is inappropriate. dosage of 5 mg/kg body weight to a • acid fast bacilli (AFB) in sputum smear The success of treatment relies heavily maximum of 300 mg daily. Treatment on patient compliance and direct • cavitation on chest X-ray should be for a minimum period of nine months with appropriate supervision should be the aim of any • laryngeal TB treatment program. Compliance is monitoring for liver toxicity. • cough, particularly if productive of important to prevent the development of – Contacts with positive reactions, sputum, or drug resistance. who do not undertake treatment of • evidence of tuberculin conversion in Multi-drug resistant TB (MDRTB) latent infection, should be kept under any of the contacts. Resistance to at least isoniazid and surveillance and followed up with rifampicin (whether or not it is also Note: Tuberculosis testing should never chest X-rays taken at six months and resistant to other drugs) is classified as be omitted for child contacts. 12 months. multi-drug resistant. MDRTB is rare in Following tuberculin testing contacts can Control of environment Australia. It has remained at less than be grouped as: There are no specific environmental two percent per year in the past 15 controls as the greatest risk of • Negative reactors years. There is however a potential risk of transmission of infection is prior to MDRTB in Victoria as most of the – Tuberculin conversion takes a few diagnosis. However, a patient with patients notified each year are overseas weeks and may not have occurred pulmonary tuberculosis should be born, many from countries with high yet in these contacts. isolated from any new contacts and rates of drug resistant TB. – Testing should be repeated in eight young children (either in hospital or at to 12 weeks after a break of contact home) until at least 14 days after or in some cases initial testing may commencing appropriate anti- be delayed for eight weeks. tuberculosis treatment. 150 The blue book: Guidelines for the control of infectious diseases

Fresh air, sunlight and covering the Health care facilities are required to have mouth and nose when coughing are all protocols and guidelines for tuberculosis appropriate patient education and prevention and management in place, environmental control measures. including a tuberculin skin test screening policy (refer to Management, control and Outbreak measures prevention of tuberculosis guidelines for It is unusual for an outbreak of TB to health care providers, Department of occur due to the chronic nature of the Human Services 2002). disease and the extended incubation International measures period. In the event of two or more cases All countries are required to report TB occurring concurrently in a single setting, surveillance data to the World Health contact tracing and investigation would Organization. This data informs policies be extended to identify a possible and strategies aimed at the global unknown source case. control of TB. Migrants and long term Special settings visitors to Australia are screened for Nosocomial transmission of tuberculosis evidence of TB prior to being granted a does occur, particularly in cases where visa. diagnosis is delayed. It is important that a high index of suspicion for tuberculosis Additional sources of information is maintained, particularly in patients • Victorian Department of Human with respiratory symptoms and belonging Services 2002, Management, control and to a high risk group for TB such as prevention of tuberculosis. Guidelines for overseas born from high prevalence health care providers (2002–2005), countries, immunosuppressed patients http://www.health.vic.gov.au/ideas and the elderly (both Australian and • World Health Organization, overseas born). http://www.who.int All suspected and active cases of tuberculosis must be placed in respiratory isolation and appropriate infection control measures implemented, including use of submicron or particulate filter masks for health care workers and surgical masks for patients during transport within the hospital. In the event of a health care worker being exposed to an undiagnosed case of tuberculosis, appropriate contact tracing and screening measures must be implemented. Investigation and management will be as for contacts (above). The blue book: Guidelines for the control of infectious diseases 151

Mycobacterium ulcerans

Victorian statutory requirement Method of diagnosis Incubation period Mycobacterium ulcerans infection (Group Swabs from beneath the undermined This has not been clearly defined but is B disease) must be notified in writing edges of the lesion or a biopsy should be thought to be quite long, i.e. weeks to a within five days of diagnosis. sent for staining for acid-fast bacilli couple of months. (AFBs). Two other swabs should be School exclusion is not required. taken; a dry swab for a polymerase chain Public health significance Infectious agent reaction (PCR test) and another for and occurrence Mycobacterium ulcerans is a member of culture should be placed in transport Although this is not a common cause of the mycobacterium family. Tuberculosis, medium. Bacterial culture or a specific ulcers in Australia, it is important that it leprosy and many other environmental PCR should be performed to confirm the be considered in the focal areas in which mycobacteria belong to this family. diagnosis. It should be stated on the it occurs as early diagnosis and Mycobacterium ulcerans causes skin request form that treatment is advisable to minimise tissue ulcers, variously known as the Bairnsdale M. ulcerans is suspected. damage. ,Bairnsdale, Buruli, or Daintree ulcer. A positive smear for AFBs makes the After tuberculosis and leprosy this is the diagnosis likely. Culture or PCR is most common mycobacterial disease. The Identification required for confirmation. A negative disease exists or is suspected in 31 Clinical features smear does not exclude the diagnosis. countries. The majority of the cases occur The first sign of M. ulcerans is usually a in foci in west and central Africa, where The PCR test is performed at the painless, non-tender nodule or . It large, severe disabling ulcers may result in Victorian Infectious Diseases Reference is often thought to be an insect bite. The severe contractures or death from Laboratory (VIDRL). This test can give lesion may occur anywhere on the body extensive skin loss. but it is most common on exposed areas rapid confirmation of the diagnosis within In Australia the disease exists in Far of the limbs. Some patients complain a few days. Culture of the organism North Queensland around the Mossman that the lesion is itchy. In one or two usually takes 8–12 weeks. area and in parts of coastal Victoria months the nodule may become A biopsy of suspicious lesions which including East Gippsland (where it was fluctuant and ulcerate, forming a have not ulcerated can be sent for first described in Bairnsdale and so characteristic ulcer with undermined histology. The suspected diagnosis named), Cowes on Phillip Island, edges. Ordinarily there is no regional should be mentioned and a request Mornington Peninsula and most recently lymphadenopathy, fever or systemic made for AFB staining, specific PCR and Bellarine Peninsula. manifestations associated with the bacterial culture. Biopsy specimens disease. If left untreated extensive usually show extensive necrosis, Reservoir ulceration can occur. especially of fat. Granulomatous The organism appears to be associated Occasionally the disease may present as inflammation is usually present in more with usually swampy or stagnant water. a firm, painless elevated plaque with chronic lesions. AFBs are frequently seen The exact reservoir remains unclear. irregular edges. Or an entire limb or area in large numbers. may be indurated by oedema without an ulcer being present. The oedematous form may be associated with fever. 152 The blue book: Guidelines for the control of infectious diseases

Mode of transmission Control of case Control of environment The exact method of transmission of M. Isolation is not required. The ulcers do Not applicable. ulcerans infection is unclear. Exposure to however contain large numbers of contaminated water, soil, or vegetation in organisms and it is possible that person Outbreak measures areas where the disease is known to to person infection could occur through Clusters of cases are investigated looking occur is thought to be required. The breaks in the skin. Thus, it is for a common source where an bacteria may enter through a breakage in recommended that ulcers be kept intervention may be feasible and the skin. Exposure to aerosols of covered and thorough hand washing be advisable, including health or public contaminated water has been performed following dressing changes. alerts. Safe disposal of infected material should hypothesised to be a method of Additional sources of information acquisition. Recently, some insects that also occur. • World Health Organization, live in water have been shown to contain The current mainstay of treatment is www.who.int/topics the bacteria and they may play a role in surgery with adequate (but not transmission. excessive) clearance of the undermined edges of the ulcer. Primary closure may Period of communicability be possible with small lesions but skin M. ulcerans infection is not (or is rarely) grafting of the area may be required for transmitted from one person to another. larger areas. Other forms of treatment Susceptibility and resistance that may be used, often as an adjunct to Everyone is susceptible to infection. surgery, include: • Heat treatment. Continuous local Control measures heating promotes healing but care Preventive measures must be taken to prevent burning. The Early recognition and diagnosis is organism grows at 32˚C and heat up important to minimise the disabling and to 40˚C has been used with some disfiguring effects of this disease. effect. Referral for treatment by doctors experienced in the management of this • Antibiotic treatment. A number of condition is recommended. Simple antibiotics have been found to be precautionary measures such as wearing active against the organism in vitro. appropriate protective clothing when These include clarithromycin, gardening and undertaking recreational rifampicin, azithromycin and amikacin. activities in identified risk areas may Combinations of these have been assist in preventing infection. Cuts and used, often to mop up residual abrasions should be cleaned promptly organisms after surgery in an attempt and exposed skin contaminated by to prevent recurrence. suspect soil or water should be washed Occasionally small lesions have been following outdoor activities. reported to heal spontaneously. BCG vaccination is not used for Control of contacts prophylaxis. Not applicable. The blue book: Guidelines for the control of infectious diseases 153

Pediculosis or head lice

Victorian statutory requirement Incubation period Mode of transmission Notification is not required. The life cycle consists of three stages: Pediculosis is transmitted through direct School exclusion: readmit the day after egg, nymph and adult. The eggs are head to head contact with a person with appropriate treatment has been known as nits and hatch in six to seven head lice. Nymphal and adult lice survive, commenced. days. There are three nymphal forms that dependent on the humidity of the each last one to eight days. environment, and according to Infectious agent The female lays the first egg one or two Queensland research usually die within Pediculus humanus var. capitus is the days after mating and can lay 24 hours of being stranded away from infective agent. approximately three to eight eggs per day the head. There is no significant risk of for the next 16 days. After a life span of transmission from the environment. Identification 32–35 days the louse dies. Clinical features Period of communicability Pediculosis is commonly said to be Public health significance Communicability continues as long as associated with an itchy scalp however and occurrence lice or their nymphs remain alive. this is an unreliable sign. Itching is only Head lice have been associated with Susceptibility and resistance experienced in 14–50% of people with humans for 10 000 years. Head lice Everyone is susceptible to infection. head lice. Head lice can be present for occur worldwide. Anyone can get lice weeks or even months without causing and given the opportunity head lice will Control measures an itch. Secondary scalp infections move from head to head without Preventive measures resulting from scratching can occur but discrimination. They are frequently Regular checking using the method are rare. associated with children. known as ‘conditioner and combing’ Method of diagnosis Information on the prevalence of head allows early detection of head lice and Early detection makes treatment and lice varies around the world. In 2002 the will limit the establishment of large control of head lice easier. Traditional prevalence of head lice among primary outbreaks. scalp inspection is a poor method of school children in Victoria was found to Control of case detecting lice. It can result in 30% false be 13%. Females were more than twice Treatment should concentrate on the positive and 10% false negative findings. as likely to have head lice as males. head. There is no evidence that the The technique known as ‘conditioner and The prevalence of head lice in primary environment is a significant cause of combing’ is the most effective method school aged children in other parts of reinfection. for detection. This involves combing Australia is reported to be up to 60%. The conditioner and combing method white hair conditioner through dry, Head lice are not vectors of infectious can be repeated every second day until brushed hair. The next step is to divide disease. Louse-borne relapsing fever, no lice are found for ten days. the hair into smaller sections and to and , none of which comb each section using a head lice If using an insecticidal product it is occur in Australia, are all associated with comb. After each combing the comb is important to use a ’registered’ or ’listed’ the body louse Pediculus humanus var. wiped on to a tissue. This allows lice and product which should have two corporis. eggs to be easily seen. The aim is to applications seven days apart. Applying with the least amount of water possible cylindrically coat each hair in conditioner Reservoir and the removal of as many eggs as and continue to comb hair until the Humans are the only reservoir. The lice possible will optimise the treatment. majority of conditioner is removed. of other animals are not transmissible to humans. 154 The blue book: Guidelines for the control of infectious diseases

Increasing resistance to the products has Outbreak measures Additional sources of information been reported and each head lice Schools • De Maeseneer, J, Blokland, I, Willems, S product should be tested after 20 While head lice are often associated with et al. 2000, ‘Wet combing versus minutes to ensure it has killed the lice. schools they are not necessarily spread traditional scalp inspection to detect Control of contacts in schools. Schools experiencing head lice in school children: Contact tracing is recommended. difficulty should encourage families to observational study’, BMJ, vol. 321, no. check for lice using the combing and 7270, pp. 1187–8. All household members or people who conditioner method on a weekly basis, or have had head to head contact with the • Spear, R, Thomas, G, Cahill, C 2002, more often during an outbreak. Even on case should be examined for head lice. ‘Head lice are not found on floors in receipt of a single case report of head Preferably this should be done using the primary school classrooms’, Aust N Z J lice, parents or guardians of all children conditioner and combing detection Public Health, vol. 26, no. 3, pp. from the class should be asked to screen method and repeated every two days for 208–11. their child at home utilising the ten days. conditioner and comb method. Parents • Victorian Department of Human Special settings or guardians should then report any Services, http://www.health.vic.gov.au/ Hairdressing salons active head lice following the headlice/ Head lice rarely fall from the head. Data synchronised home screening. from James Cook University show head If there is a cluster of cases in a class, for lice on combs and brushes are easily example 10% of pupils, a further school killed by immersion in hot water at 60ºC wide management program could be for one minute. There is then no considered (see resources for schools, subsequent risk of transmission from the www.health.vic.gov.au/headlice) comb or brush to the next client. The blue book: Guidelines for the control of infectious diseases 155

Pertussis (whooping cough)

Victorian statutory requirement from repeated vomiting, occasionally for younger children. Australia Pertussis infection (Group B disease) occur. experiences an epidemic of whooping requires written notification within five Method of diagnosis cough about every three or four years. days of diagnosis. Pertussis can be diagnosed on a clinical As it is not possible to completely control School exclusion for cases and contacts basis if the patient has an acute illness pertussis with the current vaccine, the is: lasting more than 14 days without highest priority should be given to another apparent cause, a classical protecting infants under 12 months of • cases should be excluded for five days paroxysmal cough with whooping and age. after commencing antibiotic treatment post-tussive vomiting. However bouts of The World Health Organization (WHO) • unimmunised sibling contacts under coughing may occur without whoops or estimates there were 40 million cases of seven years of age and unimmunised vomiting and the disease may only be pertussis in 1994 and 360 000 deaths. close child care contacts must be suspected if the patient is a contact of a WHO believes only one to two per cent excluded from school and children’s known case. Apnoea may be the only of cases are reported. In industrialised services centres for 14 days from the manifestation in infants. Laboratory countries four children out of every 10 last exposure to infection, or until they confirmation can be problematic but 000 infected die from pertussis and its have taken five days of a ten day should be sought where possible. A complications. In Australia the first course of antibiotics. nasopharyngeal aspirate or swab is the pertussis vaccine was manufactured in Infectious agent best specimen to obtain to culture the the 1920s. There is a clear seasonal bacterium. The likelihood of such cultures . pattern with 65% of notifications being positive is reduced 21 days after occurring over the spring and summer Identification the cough onset or if effective months. Clinical features antimicrobial therapy has commenced The catarrhal state may be against Reservoir indistinguishable from a viral upper B. pertussis. Serology using B. pertussis Humans are the only known natural respiratory tract infection. The infection specific IgA may be falsely negative but a reservoir of B. pertussis. damages respiratory epithelium, positive result is highly reliable in the Mode of transmission producing respiratory obstruction and presence of appropriate symptoms. B. pertussis is highly infectious. It may be paroxysmal coughing. There is often a Incubation period spread from person to person by close characteristic whoop. This is a crowing The incubation period is usually between contact, usually by respiratory aerosols, sound during inspiration preceding a six and 20 days. It is most commonly infecting 70–100% of household bout of coughing. about 14 days. contacts. There is little fever. Apnoea, and encephalopathy may occur in very Public health significance Period of communicability severe cases. Infants aged less than six and occurrence It is highly communicable in the early months and adults often do not have the It is a distressing and often serious catarrhal stage before the onset of characteristic whoop. Paroxysms illness particularly in children under one paroxysmal cough. Thereafter frequently end with the expulsion of year of age. The mortality rate is 0.5% in communicability decreases and clear, tenacious mucus. This is often infants under six months. High becomes negligible in about three followed by vomiting. immunisation levels reduce the number weeks. When treated with a macrolide Pneumonia is the most common cause of cases and good nutrition and medical antibiotic the period of infectivity usually of death. Fatal encephalopathy, which is care reduce case fatality. Many lasts five days or less after probably hypoxic, and severe weakness vaccinated adults may have mild commencement of therapy. infection and act as a source of infection 156 The blue book: Guidelines for the control of infectious diseases

Susceptibility and resistance days is no longer infectious and antibiotic Outbreak measures Maternal antibodies do not protect treatment and school exclusion are not See Control of contacts, above. needed. Antibiotic treatment is required newborns against infection. Severity is Clusters of infection are managed on a if there is complicating pneumonia. greatest in young infants while milder and case-by-case basis. Contact the Consult the current version of atypical cases occur in all age groups. Department of Human Services for Therapeutic guidelines: antibiotic Incomplete immunisation, waning further advice. immunity and the fact that vaccine (Therapeutic Guidelines Limited). efficacy is 70–80%, results in cases Control of contacts Additional sources of information occurring in older children and adults. Erythromycin should not be given if more • Communicable Diseases Network Lifelong immunity is not guaranteed, than 14 days have elapsed since the first Australia 1997, Guidelines for the even after clinical disease. contact with the infectious case (doses control of pertussis in Australia, and duration as for cases). In special Communicable Diseases Intelligence Control measures circumstances, such as a high risk Technical Report Series, Preventive measures exposure for an infant contact, antibiotics http://www.health.gov.au Educate the public to the dangers of may be given within 21 days of first whooping cough and the advantages of • PHLS Communicable Disease contact with an infectious case. initiating immunisation at two months of Surveillance Centre 2002, ‘UK Antibiotics rarely prevent secondary age and adhering to the immunisation guidelines for use of erythromycin transmission and should be limited to schedule (DTPa at two, four and six chemoprophylaxis in persons exposed household or child care contacts at high months and four and fifteen years of to pertussis’, Journal of Public Health risk of severe complications that have age). Delay immunisation only for Medicine, vol. 24, pp. 200–206. had direct contact with an infectious significant intercurrent infection or an case: evolving neurological disorder. Minor respiratory infections are not a contra- • infants <12 months of age regardless indication for immunisation. of vaccination status Control of case • any child aged between 12 and 24 Antibiotics will have little effect on the months who has received less than clinical course of disease but can reduce three doses of pertussis vaccine the risk of transmission if commenced • any women in the last month of within 21 days of cough onset. Treatment pregnancy generally consists of erythromycin or • any child or adult who attends or works clarithromycin. If it is not tolerated at a child care facility. alternative macrolides with fewer side effects may be considered. A patient Control of environment who has been coughing for more than 21 Not applicable. The blue book: Guidelines for the control of infectious diseases 157

Pinworm infection (threadworm)

Victorian statutory requirement Incubation period Period of communicability Notification and school exclusion are not The lifecycle requires two to six weeks to Communicability continues as long as required. complete. The eggs are fully embryonated the eggs are being discharged on the and are infective within a few hours of perianal area. The eggs can survive for Infectious agent being deposited. Male and female several days in the right conditions. Enterobius vermicularis is an intestinal pinworms vary in size ranging between Reinfection from contaminated hands is nematode. 2–13mm in length, up to 0.5mm wide common. and are yellowish white in colour. A long, Identification thin and sharply pointed tail distinguishes Susceptibility and resistance Clinical features the female worm. Infection does not confer immunity. In the majority of children and adults infection is asymptomatic. Migration of Public health significance Control measures the female worm from the rectum then and occurrence Preventive measures anus to lay eggs on the perianal skin The pinworm is the most common • Effective hand washing, particularly during the night can lead to perianal helminth parasite of temperate regions. before eating or preparing food. pruritus or disturbed sleep or irritability. These infections are found worldwide • Keep nails short, discourage scratching Sometimes secondary infection of the and affect all socio-economic groups. bare anal area and biting. scratched skin occurs. In children the Less attention is paid to the pinworm in pinworm can cause vulvovaginitis during • Daily bathing or showering. tropical regions of the world presumably its migration from the anus. • Change to clean underwear, because of the prevalence of more Pinworms or their eggs have occasionally nightclothes and bed sheets frequently important parasites. Pinworm infections preferably after bathing. been detected at other sites such as the predominantly affect paediatric liver and lung. Rarer clinical populations where the prevalence is Control of case manifestations include salpingitis, pelvic reported to between 10–50% in some There are a number of drugs available for pain and the formation of granulomas in groups. treatment including pyrantel pamoate, the peritoneal cavity. mebendazole or albendazole. Consult the Method of diagnosis Reservoir current version of Therapeutic guidelines: The diagnosis should be suspected in Humans are the only reservoir. Pinworms antibiotic (Therapeutic Guidelines children with a perianal itch and this is of other animals are not transmissible to Limited). confirmed by detection of their humans. Care should be taken to change linen and underwear of infected person daily characteristic eggs. Applying clear sticky Mode of transmission tape ({with sticky side outward) to the for several days after treatment with care Pinworms are transmitted by direct perianal skin and examining it for eggs is to avoid dispersing the eggs into the air. transfer of infected eggs by hand from the best way to make the diagnosis. This anus to mouth of the same or another Control of contacts is best done in the morning prior to person. It can also be transmitted Not applicable. bathing, as the worms migrate during indirectly through bedding, clothing, food Special settings resting periods. Microscopy on faeces or other articles. Spread is facilitated by Public health education on the can be conducted although finding eggs conditions of overcrowding. importance of hand washing may assist. is exceptional. Outbreak measures Not applicable. 158 The blue book: Guidelines for the control of infectious diseases

Additional sources of information • Markell, E, John, D, Krotoski, W 1999, Markell and Voge’s medical parasitology, 8th edn, ed Saunders. The blue book: Guidelines for the control of infectious diseases 159

Plague

Victorian statutory requirement All forms of plague infection may Untreated has a case Plague (Group A disease) must be progress to septicaemic plague with fatality rate of about 50–60%. Case notified immediately by telephone or fax bloodstream spread around the body, fatality rates are significantly higher for followed by written notification within five including to the meninges. This includes pneumonic and septicaemic plague. days. some with no preceding localising signs Given that techniques for mass or buboes. Sepsis may lead to Plague is subject to Australian production and aerosol dissemination disseminated intravascular coagulation quarantine. are well described the threat of a bio- (DIC). terrorist attack using plague is a potential Infectious agent Method of diagnosis public health concern. is the plague bacillus. Visualisation of characteristic ‘safety-pin’ ovoid gram-negative organisms in Reservoir Identification material aspirated from buboes, sputum No enzootic (animal) reservoir exists in Clinical features or CSF is highly suggestive of plague Australia. In affected countries wild rats Plague is an acute, severe bacterial infection. and other rodents are the natural infection usually transmitted through a reservoir. Other animal reservoirs include Fluorescent antibody (FA) testing or bite and most commonly presents as ground squirrels (especially in North antigen capture ELISA is more specific and bubonic, pneumonic or septicaemic America), rabbits, hares and domestic particularly useful in sporadic cases. forms. cats. Seroconversion using the passive Initial symptoms are often non-specific Plague bacteria are killed within a few haemagglutination (PHA) test is also and may include fever, chills, muscle hours of exposure to sunlight although highly suggestive of recent infection. aches, nausea and lethargy. they may persist for several weeks in Bubonic plague is the most common The diagnosis is confirmed by culture water and on moist grains and . form. It is characterised by swelling and and identification of the organism from Mode of transmission inflammation of the local lymph nodes bubo aspirates, the blood, CSF or Plague is most commonly transmitted (buboes) draining the site of the flea bite sputum. from rodent to human by the bite of an or elsewhere. The nodes are tender, firm Incubation period infected flea, especially the oriental rat and fixed, and may suppurate in the The incubation period is from one to flea Xenopsylla cheopis. second week. seven days. For primary plague Respiratory droplets from people or Pneumonic plague may be primary due pneumonia it is one to four days. domestic pets with plague pharyngitis or to respiratory transmission from an pneumonia may also transmit plague. external source, or secondary as a Public health significance Unprotected handling of plague infected complication of bubonic plague. Onset of and occurrence animal tissues or laboratory specimens primary plague pneumonia is usually Y. pestis is not endemic in Australia but it are also possible aerosol routes for abrupt with high fever, and is widely distributed around the world. plague transmission. headache. Cough develops within 24 The World Health Organization (WHO) hours. Sputum is mucoid at first and reports 1000 to 3000 cases of plague If plague bacteria were to be used as a then becomes bright red and foamy. every year. Plague is endemic in some bioterrorist agent, it would most likely be Chest X-rays show a rapidly progressing parts of South East Asia including parts spread in the form of an aerosol or an pneumonia. of Indonesia, Burma and Vietnam. Wild aerosolised powder. This would result rodent plague exists in areas of the USA, primarily in pneumonic plague. A South America, Africa, Central and South deliberate release of infected is also East Asia. possible. 160 The blue book: Guidelines for the control of infectious diseases

Period of communicability For cases with bubonic plague, if there Special settings Infected fleas may remain infectious for are no respiratory symptoms contact The control measures described above months. precautions are indicated until the apply to all settings. completion of at least three days of Bubonic plague is not usually transmitted appropriate antibiotic therapy with Outbreak measures from person to person unless there is clinical improvement. A single case of plague constitutes an direct contact with pus from suppurating outbreak and should be considered as a For patients with pneumonic plague, buboes. public health emergency. isolate the case to prevent droplet Pneumonic plague may be highly spread and use respiratory precautions If one or more cases are found with no communicable under appropriate until the completion of at least three history of travel to an endemic plague climatic conditions. days of appropriate antibiotic therapy area, a deliberate release of plague Patients are usually no longer infectious with clinical improvement. bacteria must be considered. after receiving 48–72 hours of Disinfect all sputum and purulent If a focus of infection is identified, appropriate antibiotic treatment. discharges and soiled articles outbreak control measures should Susceptibility and resistance concurrently. include: Everyone is susceptible to infection. The Use respiratory and contact precautions • active case finding disease does not always confer during the handling, and autopsy, of • alerting medical practitioners protective immunity. bodies of patients suspected, or • alerting specialist treatment centres confirmed of dying from plague. Control measures • release of appropriate public Preventive measures Control of contacts information A vaccine is available against plague that Contacts of the case should be • instigation of intensive flea control provides some short term protection. It identified, examined for and, if around the focus in expanding circles may be recommended for laboratory appropriate, disinfested of fleas. of control workers handling plague specimens and Contacts are placed under surveillance visitors to epidemic areas but should not to detect symptoms of early infection for • destruction of rodents within affected be relied upon as the sole prevention six days from the last exposure. areas measure. Close contacts of confirmed or • control of contacts (as described The vaccine is not protective against suspected pneumonic plague cases above) including field workers involved primary pneumonic plague. should also be given chemoprophylaxis in environmental control measures. (doxycycline or ciprofloxacin) supervised Control of case by an experienced physician. International measures Hospitalise the case in a single room. Governments are required to notify WHO Control of environment Treatment usually consists of gentamicin and adjacent countries of the first cases As currently there is no enzootic plague in or doxycycline. Consult the current of plague in any area previously free of Australia, the greatest risk of infection is version of Therapeutic guidelines: the disease within 24 hours of diagnosis, associated with overseas travel. antibiotic (Therapeutic Guidelines in accordance with International Health Limited). Any suspected local sources of infection Regulations. should be investigated and managed as a Use an appropriate insecticide to rid the public health emergency (see Outbreak patient (including clothing and baggage) measures, below). of fleas. The blue book: Guidelines for the control of infectious diseases 161

Measures applicable to ships, aircraft, land transport and international travellers arriving from plague areas are specified in the International Health Regulations 1969, third annotated edition 1983, WHO, Geneva. Prior to departure from an area where there is an epidemic of pulmonary plague, those suspected of significant exposure should be placed under surveillance to detect symptoms of early infection for six days from the last exposure. On arrival of a suspected infected ship or aircraft, travellers should be disinfested of fleas and kept under symptom surveillance for six days from the date of arrival.

Additional sources of information • Australian Government Department of Health and Ageing fact sheet, http://www.health.gov.au • Centers for Disease Control and Prevention, Atlanta USA, Public health emergency preparedness and response, http://www.bt.cdc.gov 162 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 163

Poliomyelitis

Victorian statutory requirement After 60 days the degree of existing by the Victorian Infectious Diseases Poliomyelitis (Group A disease) must be paralysis is likely to be permanent. Reference Laboratory. The NPRL can also notified immediately by telephone or fax Sensory loss is very rare and its differentiate between ‘wild-type’ and followed by written notification within five occurrence should strongly suggest vaccine-associated strains. days. some other diagnosis such as Guillain- The Department coordinates with Barré syndrome. School exclusion: applicable for at least 14 clinicians and the NPRL to ensure that days from onset. Re-admit after receiving Post-polio syndrome is an infrequent appropriate infection control procedures medical certificate of recovery. recurrence of muscle weakness that may are followed in the collection, transfer occur many years after initial infection. It and analysis of all clinical specimens Infectious agent is thought to be due to progressive from patients with suspected polio. Poliovirus is an enterovirus; types 1, 2 dysfunction and loss of motor neurons and 3 cause disease. that compensated for the neurons lost Incubation period during the original infection, not to The range is between three to 35 days Identification persistent or reactivated poliovirus with seven to 14 days for paralytic cases. Clinical features infection. The majority of polio infections are either Public health significance inapparent or present as a non-specific Vaccine-associated paralytic and occurrence febrile illness. Flaccid paralysis occurs in poliomyelitis (VAPP) is a very rare Prior to vaccination programs polio less than 1% of poliovirus infections. complication in recipients of oral polio occurred worldwide. Since the Global vaccine or their contacts, with Polio Eradication Initiative was launched Symptoms of minor illness include fever, approximately one case per 2.4 million in 1988, three WHO regions have been malaise, headache, nausea and vomiting. doses of vaccine. The risk is greater for certified polio-free: the Americas in If the disease progresses to major illness, the first dose than subsequent doses 1994, the Western Pacific (of which severe muscle pain and stiffness of the and is slightly greater for adults than Australia is a member) in 2000, and neck and back with flaccid paralysis may children. Europe in 2002. Polio cases have occur. Method of diagnosis dropped from an estimated 350 000 in The most characteristic feature of polio A clinical history including vaccination 125 countries in 1988 to just 480 paralysis is its asymmetric distribution, status of case and household contacts reported cases in only ten polio-endemic which affects some muscle groups while and any recent travel is important. countries in 2001. sparing others. Fever and muscle pain By 2003, six countries were still are generally present at onset with the Diagnosis is made by isolation of virus reporting new polio cases: India, Niger, maximum extent of paralysis usually from cerebrospinal fluid (CSF), faecal Pakistan, Afghanistan, Egypt, and Nigeria. reached within three to four days. specimens or oropharyngeal secretions. Progression of paralysis almost invariably Two separate faecal specimens taken at In endemic areas, cases of polio occur halts when the patient becomes afebrile. least 24 hours apart and within 14 days both sporadically and in epidemics. In The site of paralysis depends upon the of onset of symptoms give the best temperate climates an increase in cases location of nerve cell destruction in the chance of diagnosis. CSF usually reveals occurs during the late summer and spinal cord or brain stem. Proximal a mild elevation in protein and a autumn, in tropical countries an increase muscles of the extremities tend to be lymphocytosis. is less pronounced but can occur as a more involved than distal. The legs are The Department requires that all seasonal peak in the rainy season. more often affected than the arms. suspected cases of polio have In countries where polio has been Paralysis of the respiratory and appropriate faecal specimens sent for eradicated, importation from non- swallowing muscles is life threatening. analysis by the National Poliovirus vaccinated individuals remains a threat. Reference Laboratory (NPRL), managed 164 The blue book: Guidelines for the control of infectious diseases

Polio remains a predominantly childhood Susceptibility and resistance Under the National Immunisation illness with 80% to 90% of cases All non-immune people are susceptible Program, polio immunisation consists of occurring in children less than five years to infection. a primary course of OPV given as two old. drops by mouth at 2, 4 and 6 months of After infection from both clinically age with a booster at four years of age. recognisable and inapparent infections, Reservoir IPV is given for individuals with type specific lifelong immunity occurs. Humans. immunosuppression from disease or Reinfection is rare but can occur if chemotherapy and for their siblings and Mode of transmission infected with poliovirus of a different household contacts. Wild poliovirus is spread through faeces type. Both IPV and OPV give mucosal and and saliva. It is primarily transmitted Vaccine efficacy of OPV and Inactivated humoral protection, however IPV through faecal-oral spread and is an Polio Vaccine (IPV) after a primary course produces considerably lower levels of important consideration where sanitation is 95% and thought to be life long. Both intestinal immunity than OPV. is poor. vaccines give protection against all three ‘Live’ oral polio vaccine (OPV) virus can types of poliovirus. Due to the successful elimination of polio in some regions and the concern with be shed in the faeces for six weeks and Infants born of immune mothers have OPV of Vaccine Associated Paralytic may lead to infection in unvaccinated transient passive immunity. contacts. Unvaccinated household Poliomyelitis (VAPP), many industrialised contacts of a case should be vaccinated Control measures countries have now changed to IPV alone at the same time. Stressing the Preventive measures for routine immunisations. IPV is the importance of hand washing for parents Universal vaccination in early childhood vaccine recommended on the ASVS following nappy changing and disposal is is the most effective means of preventing subject to the availability of further important. and eradicating poliomyelitis. Catch-up combination vaccines. The Australian immunisation is also recommended for Government is currently reviewing this Period of communicability unimmunised or partially immunised funding decision. The risk of transmission of infection is adults at risk of exposure such as those OPV is still recommended in developing greatest for the seven to ten days prior to travelling overseas and health care countries because of the higher risk of and following the onset of symptoms. workers in possible contact with polio exposure to wild poliovirus, the low cost The virus persists in the pharynx for cases. of the vaccine, the ease of its approximately one week and in the Immunisation can be given as an administration and its excellent capacity faeces for up to six weeks, or longer in intramuscular IPV, or as a live OPV. to provide population-level immunity. the immunosuppressed. Transmission of the virus is possible for as long as the virus is excreted. The blue book: Guidelines for the control of infectious diseases 165

Control of case Control of environment There is no specific treatment against In communities with modern sewerage poliovirus. Cases require expert systems, faeces and urine can be supervision and may need ventilation disposed of directly into the system support. Early physiotherapy may without preliminary disinfection. increase the level of function and reduce Cases and carers should be advised the risk of physical deformities as a result about the importance of strict hand of paralytic polio. washing, covering the mouth when Enteric precautions should be initiated in coughing, sneezing into disposable hospital settings. These are often of little tissues, and the appropriate cleaning or benefit in household settings as disposal of contaminated objects. susceptible contacts are likely to have been exposed prior to diagnosis. Outbreak measures In countries such as Australia where In communities with appropriate modern polio has been eradicated a single case sewerage systems, faeces and urine from of polio is considered a public health infected patients can be disposed of emergency and the Department of directly into sewers without preliminary Human Services must be notified disinfection. Terminal disinfection is immediately. The Department required for all other potentially investigates to: contaminated items. • determine whether the patient’s Control of contacts disease represents an indigenous, Vaccination of families and other close imported or VAPP case contacts is recommended but may not contribute to immediate control due to • if believed to be a VAPP case, obtain susceptible contacts often being infected details of vaccine history, batch by the time the first case is recognised. number, virus type, severity and persistence of residual paralysis 60 Active case finding, especially among days after onset children, ensures early detection of related cases and facilitates control. supervise all appropriate case and contact control measures, as outlined above. 166 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 167

Psittacosis (ornithosis)

Victorian statutory requirement positives may occur in C. pneumoniae, C Mode of transmission Psittacosis (Group B disease) must be trachomatis and occasionally in Infection is generally acquired by inhaling notified in writing within five days of Legionella infections. dust from dried faeces or fresh or dried diagnosis. Antibiotic treatment may delay or ocular and nasal secretions from infected School exclusion is not applicable. attenuate antibody formation so birds. Direct contact with birds is not convalescent sera should be taken at required for infection. Rare person to Infectious agent least two weeks after the acute person transmission has occurred. Chlamydia psittaci is an obligate specimen. intracellular bacterium. Period of communicability Culture of the organism is generally not Infected birds may shed the agent Identification performed because of danger to intermittently for a prolonged period. Clinical features laboratory workers. Shedding may be precipitated by stress The onset of psittacosis is usually abrupt Birds on the birds such as cold, crowding or with fever, prominent headache, Birds suspected of being infected should shipping. Dried secretions may remain photophobia, myalgia, and upper or lower be referred to a veterinarian for diagnosis infectious for many months. respiratory tract symptoms. Dry cough is and treatment as required. The Avian a common feature. -temperature Medicine Section at Primary Industries Susceptibility and resistance Chlamydia psittaci is highly infectious. At dissociation, splenomegaly and rash may Research Victoria, Attwood (03) 9217 risk groups include bird owners, pet shop occur. In association with pneumonia 4200 has further details of specimen employees, veterinarians, poultry- these are said to be suggestive of the collection and transport requirements. diagnosis. Chest X-rays may show patchy processing workers, zoo workers and or focal consolidation. Incubation period taxidermists. The incubation period is four days to four The illness usually lasts for seven to ten Older adults and pregnant women may weeks, commonly ten days. days and is mild or moderate. It may be have a more severe illness. Immunity following infection may be incomplete severe in pregnant or older, untreated Public health significance and reinfection occurs occasionally. patients. Asymptomatic infection or mild and occurrence flu-like illness may also occur. Most cases are sporadic but outbreaks Control measures Complications include encephalitis, of infection may occur rarely within Preventive measures endocarditis, myocarditis and individual households or through contact Educate the public about the danger of thrombophlebitis. Relapses may occur, with affected pet shops or poultry household or occupational exposure to especially when there has been processing plants. infected pet birds. inadequate treatment. Reservoir Wearing gloves and dust masks is Method of diagnosis Birds of all types act as a reservoir. This recommended when cleaning areas with Humans is especially common for psittacine birds which birds have frequent contact such Infection is generally diagnosed by (parrots, lorikeets, cockatiels, as cages and bird feeders. seroconversion on paired acute and budgerigars) but also pigeons, turkeys, Prevent or eliminate infections of birds by convalescent phase sera, although a ducks and occasionally chickens. quarantine and antibiotic treatment. single high acute phase titre in the Healthy birds may be carriers. Cats, Appropriate surveillance of commercial setting of clinically-compatible illness is dogs, goats or sheep may be infected but flocks, pet shops and aviaries should be significant. Low positive titres are this is rare. common in high risk groups. False instituted. 168 The blue book: Guidelines for the control of infectious diseases

Destroy or treat infected birds and Outbreak measures disinfect premises. All cases should be thoroughly Control of case investigated in order to identify more Isolation is not necessary, but instruct extensive outbreaks. the patient to cough into disposable Outbreaks should be reported to the tissues. Treatment with tetracyclines Department of Human Services, Victoria. should be continued for 10–14 days after fever settles. If tetracyclines are Additional sources of information contraindicated erythromycin can be • Centers for Disease Control and used. Consult the current version of Prevention 2000, ‘Compendium of Therapeutic guidelines: antibiotic measures to control Chlamydia psittaci (Therapeutic Guidelines Limited). infection among humans and pet birds’, Morbidity and Mortality Weekly Control of contacts Report, vol. 49, RR08, pp. 3–17, A diagnosis of psittacosis should be http://www.cdc.gov/mmwr considered in symptomatic contacts. Control of environment If birds were recently purchased the origin of suspected birds should be traced. This is the responsibility of the Department of Human Services in liaison with the Department of Primary Industries. Prophylactic use of tetracyclines can suppress, but not eliminate, infection in flocks and may complicate investigations. For disinfection of floors and cages use a 1:100 dilution of household bleach in water or 70% isopropyl alcohol. Psittacosis information sheet

What is psittacosis? What about my pet bird? Further information Psittacosis is bacterial disease of both Sick birds may have eye or nasal • Your local doctor wild and domestic birds that can affect discharge or ruffled feathers, and may • Better Health Channel, people. In birds it is also known as avian feed poorly. If your bird is ill seek advice www.betterhealth.vic.gov.au chlamydiosis (AC). from your vet. Stop wild birds getting close to your pet bird’s cage as they can • Victorian Department of Human What are the symptoms in spread disease. Services, 1300 651 160 humans? Psittacosis in humans may cause a flu- I think I may be infected - what like illness or pneumonia. Symptoms may should I do? include fever, headache, aching muscles See your local doctor and tell them about and chills, while cough is your contact with birds. This disease can characteristically dry or may be absent. If be readily treated with antibiotics. pneumonia occurs, symptoms such as shortness of breath or chest pain may How can I avoid getting occur. psittacosis? Avoid contact with wild birds and do not Where is psittacosis found? feed wild birds. Birds, especially parrots, can carry the Try to avoid stressing birds by crowding disease. Birds do not have to be sick to or cold conditions and do not buy birds spread the disease. Rarely ill cats, dogs, which appear ill. goats or sheep can spread infection. Wear gloves and a dust mask when How is psittacosis spread? cleaning cages and wet down the area The disease is spread by breathing in the prior to cleaning to prevent dust bacteria which is present in the infected formation. Don’t use an ordinary vacuum bird’s droppings, nose or eye secretions. cleaner as it can throw infectious dust Dried secretions can remain infectious into the air. for many months. The risk of getting the Clean cages, food and water bowls daily disease is greater when the birds are and use litter which creates dust such as under stress, for example just after being newspaper. bought. You may unknowingly come into Use a 1:100 diluted solution of household contact with infected birds while feeding bleach to disinfect any ill bird’s cage, wild birds, cleaning feeding stations or bowl etc. Throw away material which cleaning contaminated aviaries. The cannot be disinfected and rinse all spread of psittacosis from person to disinfected items before replacing them. person is rare. Do not allow birds to get close to your face and wash hands thoroughly after contact with birds.

Department of Human Services 170 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 171

Q fever

Victorian statutory requirement The diagnosis is supported by the Reservoir Q fever infection (Group B disease) must detection of phase II IgM by ELISA testing There is no known endemic reservoir in be notified in writing within five days of but this may not appear until 10 days Victoria. The organism is commonly diagnosis. after the onset of symptoms. Q fever IgM introduced in stock from interstate from may persist for many months after School exclusion is not applicable. animals including goats, cattle, sheep, infection; hence its presence does not other farm and domestic animals and Infectious agent necessarily confirm the diagnosis. some wild animals (including kangaroos The -like bacterium Coxiella If Q fever antibodies are present within and bandicoots). burnetii is the causative agent. three to four days of the onset of Mode of transmission symptoms it is more likely to indicate Identification Q fever is contracted through the past exposure rather than recent Clinical features respiratory route after inhalation of infection. The onset of Q fever infection is usually Coxiellae-contaminated dust or aerosols. acute and characterised by fever, chills, Chronic Q fever is suggested by a high This most commonly occurs as a result sweats, severe headache (especially CF antibody titre ( 320) to phase I and II of: antigens and low or absent IgM antibody. behind the eyes), weakness, anorexia, • inhaling water droplets and dust myalgia and cough. Transient mild rashes IgA class antibody to phase I antigen is contaminated by placental tissues, are an occasional feature. Orchitis occurs highly suggestive of Q fever endocarditis. birth fluids or excreta of infected rarely. Abnormal liver function tests are animals. Contaminated dust particles Incubation period common. may occasionally be carried downwind The incubation period is typically 19–21 Chronic complications include for a considerable distance from the days although the range is from two granulomatous hepatitis and source weeks to two months. endocarditis. The latter is the most • direct contact with contaminated serious concern as it usually involves the Public health significance materials in establishments processing aortic valve and occurs months to years and occurrence infected animals or their by-products, after the acute illness. A relapsing fatigue It is an acute febrile rickettsial disease of contact with contaminated straw, wool syndrome may occur in 20–40% of low mortality but significant morbidity. It or hides, or the contaminated clothing cases. is most commonly found in abattoir of workers. Method of diagnosis workers who have recently handled Although Q fever is occasionally Acute and some chronic manifestations contaminated stock such as feral goats transmitted sexually, there is no evidence of Q fever can be diagnosed by serology. or sheep from interstate endemic areas. of person to person transmission through It is an occupational hazard for tannery Acute Q fever can be diagnosed by a other routes. Direct transmission through and knackery workers, shearers, meat fourfold rise in specific complement blood and bone marrow transfusion has inspectors, dairy workers, animal-farm fixation (CF}) antibodies or by direct also been reported. workers, animal transporters, wool immunofluorescence (IF) antibody sorters and veterinary personnel. It also Drinking non-pasteurised milk from an testing between acute and convalescent occurs in others handling fomites such infected animal has been suggested as a sera collected at least 14 days apart. as those laundering contaminated possible route but this has not been clothing. proven. Outbreaks are usually of short duration. 172 The blue book: Guidelines for the control of infectious diseases

Period of communicability Access to high risk environments such as Outbreak measures Person to person spread occurs very rarely abattoirs and meat-processing plants All notified cases are investigated to by the sexual route. Contaminated clothing should be restricted to immunised ascertain the most likely source of may also be a source. persons. This includes visitors, exposure and to identify any other linked contractors and delivery drivers. Workers cases. If two or more cases are linked in Susceptibility and resistance in these environments should also be time and place to a workplace, other All non immune people are susceptible educated about the nature of the staff should be assessed for immune to infection. Most cases are in male disease. status (if not already known) with adults but this is probably due to their Control of case antibody levels and skin testing. higher frequency of exposure to high risk Acute cases of Q fever generally require Non-immune staff should be excluded environments, rather than differential treatment with doxycycline or from the worksite until vaccinated. susceptibility. chloramphenicol. Consult the current Infection usually confers lifelong version of Therapeutic guidelines: immunity. antibiotic (Therapeutic Guidelines Limited). Control measures Preventive measures In chronic disease or endocarditis, Immunisation of those in high risk prolonged combination therapy together occupational groups is the primary with cardiac surgery may be required. preventive measure against Q fever. Consultation with an infectious diseases There is a risk of severe local reactions to physician should be sought. the vaccine in those people previously Isolation is not necessary. Articles exposed to Q fever or the vaccine. To contaminated with blood, sputum and assess prior exposure to Q fever or the excreta should be disinfected using vaccine, pre-vaccination screening is standard precautions. necessary and involves: Control of contacts • checking for a clinical history of Q No specific measures are required for fever or Q fever vaccination household contacts. • antibody testing Vaccination during the incubation period • an intradermal skin test, read after does not prevent the disease. Post- seven days. exposure prophylaxis is not recommended. Any positive result on screening precludes vaccination. Vaccination Control of environment induces lifelong immunity in most If a clear source is identified, disinfection vaccinees. Training is recommended for can be performed using 0.05% medical practitioners intending to hypochlorite (500 ppm available conduct Q fever screening and chlorine) or 5% peroxide. vaccination. The blue book: Guidelines for the control of infectious diseases 173

Rabies and Australian bat lyssavirus

Victorian statutory requirement The criteria for a confirmed case are a Incubation period Rabies (Group A disease) must be clinically compatible neurological illness The incubation period for rabies is usually notified immediately by telephone or fax and one or more positive results from the three to eight weeks. It is rarely as short followed by written notification within five three laboratory tests described below. as nine days or as long as seven years. It days. Symptoms of encephalitis due to ABL tends to be shorter for wounds in areas Australian bat lyssavirus (Group B include numbness, muscle weakness, of the body with rich nerve supply and disease) must be notified in writing collapse and coma. A confirmed case close to the head. within five days of diagnosis. requires laboratory definitive evidence The incubation period for ABL is not well only. Rabies is subject to Australian characterised but it is assumed to be quarantine. Method of diagnosis similar to rabies. The first case, reported The Australian Animal Health Laboratory in 1996, is believed to have had an Infectious agents at Geelong is the reference laboratory for incubation period of at least several Rabies virus and Australian bat lyssavirus the diagnosis of rabies and ABL. The weeks. In the second patient the (ABL) are closely related members of the State Chief Quarantine Medical Officer at incubation period was greater than two genus Lyssavirus. the Department of Human Services years. should also be advised at the time of Identification Public health significance submitting any specimen. Transfer of Clinical features and occurrence human and animal specimens is Rabies is an acute viral disease of the Rabies is endemic in Asia, India, Africa, coordinated by the State Chief central nervous system (CNS). CNS North and South America and parts of Quarantine Medical Officer in symptoms are preceded by a non- Europe. High rates of rabies are reported consultation with the chief veterinary specific prodrome of fever, headache, from the Philippines, Thailand and officer. malaise, anorexia, nausea and vomiting Indonesia with the exception of Bali, lasting one to four days. This is followed Rabies and ABL can be diagnosed by: which is rabies-free. by signs of encephalitis manifested by • detection of virus antigen by direct Australia is currently rabies-free. Rabies periods of excitation and agitation fluorescent antibody of a clinical is a very rare infection of travellers to leading to delirium, confusion, specimen such as neural tissue endemic areas outside of Australia. Only hallucinations and convulsions. Signs of (preferred), skin snips from the nape of two imported human cases were brain stem dysfunction begin shortly the neck, saliva or CSF reported between 1900 and 1995 (1987 after with excessive salivation and • isolation in cell culture or laboratory and 1990). difficulty in swallowing. This produces the animal of the virus from saliva, CSF or Two human cases of ABL infection have classical picture of ‘foaming at the CNS tissue been reported. One of these was from mouth’. • identification of rabies-neutralising Northern New South Wales (1996) and Even with medical intervention the antibody in the serum or CSF of the other from Rockhampton in disease is almost invariably fatal. Death unvaccinated persons. Queensland (1998). Both patients had a from respiratory paralysis generally history of bites and scratches from a bat Confirmation by all the above methods is occurs within two to six days of the and both died from their infections. onset of symptoms. recommended. The criterion for a suspect rabies case is progressive encephalitis with a past history of exposure in a rabies endemic area. 174 The blue book: Guidelines for the control of infectious diseases

Rabies is subject to human quarantine ABL is known to infect all four faeces does not constitute a likely controls under the Commonwealth Megachiroptera (fruit bats and flying exposure to ABL, although bat urine and Quarantine Act 1908. Rabies is a foxes) species in Australia and at least faeces may carry other human quarantinable disease because of three species of Microchiroptera pathogens. Australia’s freedom from this disease. It (insectivorous bats). Ongoing serological Transmission from person to person is is also reportable to the World Health testing and virus studies suggest that this theoretically possible but it has only ever Organization. lyssavirus is widely distributed in been documented through corneal The primary quarantine concern is the Australia. It is therefore assumed that all transplantation. prevention of the introduction of rabies Australian bats have the potential to virus to local dog and wildlife carry and transmit ABL. Period of communicability populations. There is no evidence that lyssaviruses in In dogs and cats rabies is usually communicable three to seven days ABL is an emerging infectious disease bats can establish and spread amongst before onset of clinical signs and which has much in common with rabies. terrestrial animals, although isolated throughout the course of the illness. Viral The risk of human exposure increases cases in humans may occur on rare excretion up to 14 days prior to clinical with increasing human contact with occasions. signs has been observed in some animal Australian bat environments. This risk Mode of transmission species. Similar communicability can be would increase significantly if ABL Rabies virus and other lyssaviruses are assumed for human cases. became established in terrestrial animal usually transmitted to humans via bites Communicability for ABL is not known populations, particularly dogs. or scratches which provide direct access but assumed to be similar to rabies. Reservoir of the virus in saliva to exposed tissue and nerve endings. It can also occur Rabies is a disease primarily of animals. Susceptibility and resistance where mucous membrane exposure to Most wild and domesticated dog-species All mammals are susceptible to varying bat saliva has occurred such as eyes, (including foxes, coyotes, wolves and degrees. In one case series, only 40% of nose or mouth. jackals) are susceptible to infection. children bitten by known rabid dogs Infected dogs remain the highest risk The most frequent way that humans developed the disease. source for human transmission. Other become infected with rabies is through Control measures species include skunks, racoons and the bite of infected dogs, cats, wild Preventive measures bats. carnivorous species like foxes, raccoons, Pre-exposure vaccination is skunks, jackals and wolves, and In developed countries rabies is mainly recommended for people whose insectivorous and vampire bats. Cattle, found in wild animal hosts. Disease is occupation or recreational activities horses, deer and other herbivores can spread from wild hosts to domestic place them at increased risk of being become infected with rabies but rarely animals and humans. In contrast dogs bitten or scratched by a bat. It is also transmit the virus to other animals, continue to be the main hosts in most recommended for travellers who will be although they may transmit the disease African, Asian and Latin American spending prolonged periods (i.e. more to humans. countries, and are responsible for most than one month) in rural parts of rabies of the rabies deaths that occur People are not exposed to ABL through endemic areas (see rabies/ABL worldwide. tactile contact with bats where vaccination information sheet below). parenteral or mucous membrane Australia is one of a growing number of The World Health Organization maintains exposure does not occur. Contact such countries in the world where the animal data on rabies infected countries – see as patting bats or exposure to urine and population is free of rabies. www.who.int/csr The blue book: Guidelines for the control of infectious diseases 175

Control of case The decision to offer post-exposure Additional sources of information There is no specific treatment available. prophylaxis (rabies vaccine and rabies • Animal Health Australia 1996, Intensive supportive treatment is immunoglobulin) to a potentially exposed AUSVETPLAN, required. person should be made in consultation http://www.aahc.com.au/ The patient should be placed in a private with the Communicable Diseases ausvetplan/ Section of the Department of Human room with standard isolation precautions • Communicable Diseases Network of Services (see rabies/ABL vaccination implemented for respiratory secretions Australia 2001, Australian bat lyssavirus information sheet below). for the duration of the illness. There – Information for medical practitioners. should be concurrent disinfection of all Control of environment saliva-contaminated articles. Although See Outbreak measures, below. transmission from a patient to attending carers has not been documented, health Outbreak measures care workers should be advised to wear If the source of the ABL infection is likely gowns, gloves and masks while attending to be in Australia, a search should be patients. Blood and urine are not made for the infected animal in considered infectious. collaboration with animal health authorities. Where possible, without Control of contacts placing other persons at risk of exposure, Other individuals exposed to the source the bat should be kept and the animal are identified and offered post- Department of Human Services exposure prophylaxis. Contacts that have consulted about arranging testing of the open wound or mucous membrane bat for virus carriage. exposure to a patient’s saliva should be offered full post-exposure prophylaxis. If a rabies case, human or animal, is believed to have been locally acquired, Post-exposure treatment the AUSVETPLAN rabies control Proper cleansing of the wound is the procedures should be implemented. In single most effective measure for designated areas animal owners may be reducing the transmission of rabies virus required to have susceptible animals and this is likely to be also true for ABL. vaccinated with rabies vaccine. Animal When a person has been injured by a movements are restricted and stray potentially infected animal overseas, or animals destroyed. any Australian bat, the wound should be ABL is unique to Australia and currently it washed thoroughly for approximately five is only found in Australian bat species. If minutes as soon as possible with soap a human case of ABL is diagnosed in and water. If available, a virucidal Victoria or ABL is found in another animal antiseptic such as povidone-iodine, species such as a dog or cat, iodine tincture, aqueous iodine solution investigation and control measures or alcohol (ethanol) should be applied similar to those for a rabies case, should after washing. Exposed mucous be instigated. membranes such as eyes, nose or mouth should be flushed well with water. Rabies and Australian bat lyssavirus exposure information sheet

Pre-exposure prophylaxis Post-exposure treatment for If the exposure is connected to an Pre-exposure vaccination should be persons bitten or scratched Australian bat, where possible without recommended to those people whose The decision to offer post-exposure placing other persons at risk of exposure, occupation or recreational activities prophylaxis to a potentially exposed the bat should be kept so that the place them at increased risk of being person should be made in consultation Department of Human Services can bitten or scratched by a bat. For with the Department of Human Services. arrange for testing of the bat. example: If post-exposure prophylaxis is indicated, First aid • bat carers, bat handlers, researchers the Department of Human Services will Proper cleansing of the wound is the and students arrange for rapid delivery of vaccine and single most effective measure for immunoglobulin as required. reducing the transmission of classic • veterinarians and veterinary assistants Post-exposure treatment should be rabies virus. • veterinary laboratory staff considered in the following scenarios: Where a person has been injured by a • fruit pickers • person bitten or scratched by bats in potentially infected animal, the wound • wildlife officers (including local Australia should be washed thoroughly for approximately five minutes as soon as government officers) • person bitten or scratched by any possible with soap and water. If available, • managers of display or research animal in a country with endemic a virucidal antiseptic such as povidone- colonies of bats rabies. iodine, iodine tincture, aqueous iodine • power line workers who frequently Assessment solution or alcohol (ethanol) should be remove bats from power lines. Rabies virus and other lyssaviruses are applied after washing. Exposed mucous Pre-exposure vaccination should also usually transmitted to humans via bites membranes such as eyes, nose or mouth be recommended for travellers who or scratches which provide direct access should be flushed well with water. will be spending prolonged periods of the virus in saliva to exposed tissue (i.e. more than one month) in rural parts and nerve endings, or where mucous Post-exposure treatment – not of rabies endemic areas. The World membrane such as eyes, nose or mouth previously vaccinated against Health Organization maintains data on exposure to bat saliva has occurred. This rabies rabies infected countries – see means that people would not be exposed Rabies vaccine www.who.int/csr to lyssavirus through tactile contact with Post-exposure prophylaxis for persons bats alone or other animals where not previously immunised against rabies Pre-exposure prophylaxis consists of three parenteral or mucous membrane consists of five doses of 1.0 mL of rabies deep subcutaneous or intramuscular exposure does not occur. Contact such vaccine given as deep subcutaneous or doses of 1.0 mL rabies vaccine given on as patting bats (Australia) or other intramuscular injection, on days 0, 3, 7, days 0, 7 and 28. Doses should be given animals or exposure to their urine and 14 and 28. Doses should be given in the in the deltoid area, as rabies neutralising faeces does not constitute a possible deltoid area, as rabies neutralising antibody titres may be reduced after exposure to ABL, although bat urine and antibody titres may be reduced after administration in other sites. In children, faeces may carry other human administration in other sites. In children, administration into the anterolateral pathogens. Pre-exposure vaccination administration into the anterolateral aspect of the thigh is also acceptable. should however be offered if the person aspect of the thigh is also acceptable. The vaccine should not be administered has ongoing contact with bats. The vaccine should not be administered by the intradermal route. by the intradermal route.

Department of Human Services Rabies immunoglobulin Post-exposure treatment - Further information Rabies immunoglobulin (RIG) should be previously vaccinated against • Your local doctor given as a single dose at the same time rabies • Better Health Channel, as the first dose of the post-exposure Post-exposure prophylaxis for persons www.betterhealth.vic.gov.au vaccination course. The dose for RIG is who have previously completed the 20 International Units (IU) per kilogram recommended course of either pre- • Victorian Department of Human of body mass. RIG should be infiltrated in exposure vaccination or post-exposure Services, 1300 651 160 and around all wounds using as much of prophylaxis or who have documented • Australian Immunisation Handbook, the calculated dose as possible, and the rabies neutralising antibodies, comprises www.immunise.health.gov.au remainder administered intramuscularly. a total of two doses of rabies vaccine It should not be given at the same site as (1.0 mL each) given by either deep the vaccine, and if administered in the subcutaneous or intramuscular injection buttock, care should be taken to ensure on day 0 and day 3. In cases where prior that the dose is given intramuscularly vaccination status is uncertain, or the and not into adipose tissue. person has been vaccinated by Although the RIG and first dose of rabies inappropriate intradermal injection, a full vaccine should preferably be given on course of post-exposure prophylaxis (RIG the same day, if necessary the RIG can plus five doses of vaccine) should be be given up to seven days after the first offered. It is therefore advisable to dose of vaccine, but not thereafter. ensure that people are given adequate written documentation as to any RIG and RIG should be infiltrated into finger vaccines administered. wounds using a 25 or 26 gauge needle, and to avoid a compartment (Note that product information compression syndrome the RIG should recommends a routine 6th dose at 90 be infiltrated very slowly, and should not days. This dose is not considered cause the adjacent finger tissue to go necessary, except for immunosuppressed pale or white. If necessary a ring-block persons. See the current edition of the using local anaesthesia may be required. Australian immunisation handbook, If the wounds are severe and the National Health and Medical Research calculated volume of RIG is inadequate Council, for more information). for complete infiltration, the RIG may be diluted in saline to make up an adequate volume for the infiltration of all wounds, but as most bat bites are small and fine, this should not be necessary. 178 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 179

Rickettsial infections Includes and Queensland typhus ()

Victorian statutory requirement Fever may persist for 14 days without distribution in the rest of Australia is less Notification and school exclusion are not antibiotic treatment. The fatality rate in clear (Odorico, Graves et al 1998). The required. untreated cases is 1–40%. This increases public health impact on lives or with age and depends on the infection productivity lost is largely unmeasured Infectious agents site, the type of Rickettsiae involved and but it is suspected to be high. Numerous species of Rickettsiae are of previous exposure. concern to humans. Rickettsiae (and Reservoir Method of diagnosis their associated diseases) of particular Humans are incidental hosts and are not In endemic areas the clinical picture is importance in Australia are R. australis useful in propagating the organism in sufficiently distinctive for a clinical (, Spotted fever), nature. Scrub typhus is transmitted by diagnosis. A biopsy of the eschar can be R. tsutsugamushi (Scrub typhus), R. honei rodent mites. It occurs in a large area used to demonstrate rickettsiae by (Flinders Island spotted fever) and R. from the Indian subcontinent to Australia immunofluorescence. Specific diagnosis typhi (). and in much of Asia including Japan, is seldom possible early enough to help China, Korea and parts of Russia. The in the management. Identification reservoir also includes rats, mice and Clinical features Definitive diagnosis can be made by other small mammals. An exception is There is great variation in the severity of isolation of the rickettsia after inoculation louse-borne typhus illness produced by each organism. of the patient’s blood into mice. (R. prowazekii), which does not occur in Infection most commonly begins with a Serological methods are also available Australia. Humans are the principal papule forming at the site of the bite although these need to be interpreted reservoir for louse-borne typhus and the where the infection was introduced. This with caution because of cross-reactivity human body louse (pediculosis humanus usually becomes necrotic and forms a between strains. var humanus) is the vector. typical black eschar (scab). Four days to two weeks after the bite symptoms begin Incubation period Mode of transmission with fever and malaise followed by The incubation is from two to 14 days. The disease is not directly transmitted adenitis in the lymph glands draining the The variation in incubation may be in from person to person. Humans are bite site. As the organisms spread part related to the inoculum size. infected by the bite of an infected larval throughout the body, fever, malaise and mite or in the case of scrub typhus, a rat. Public health significance headache increase and general and occurrence lymphadenopathy occurs in most cases. Period of communicability The epidemiology varies in different parts About a week after onset the main The person is infective for lice during the of the world. Disease occurrence is often features are continuous fever, cough and febrile illness and probably two or three associated with the modification of signs of bronchitis or pneumonia, days after the temperature returns to natural habitats by humans such as photophobia, conjunctivitis, generalised normal. People are at risk of infection for when a forest is felled and replaced by a adenopathy, delirium, deafness and a as long as they remain in infected areas. secondary growth of scrub. R. australis maculopapular rash most commonly over occurs along the eastern side of Susceptibility and resistance the trunk and proximal limb parts. Australia, R. honei has been recognised All non immune people are susceptible Splenomegaly occurs in some cases. on Flinders Island near Tasmania and R. to infection and according to typhi occurs throughout many states of environmental exposure. Long-lasting Australia. Scrub typhus occurs in immunity probably follows infection. Queensland but its geographic 180 The blue book: Guidelines for the control of infectious diseases

Control measures Outbreak measures Preventive measures Except in the case of an epidemic of There is no vaccine available. People who louse borne typhus, no outbreak enter infected areas can be protected by measures are necessary. impregnating their clothing with dimethyl phthalate and renewing the repellent International measures frequently. Chemoprophylaxis can be In the event of an epidemic of louse successfully used short term and for this borne typhus occurring in Australia, the a consultation with an infectious Department of Human Services will diseases specialist is recommended. notify the World Health Organization People camping can also help prevent (WHO) and neighbouring countries of this tick bites by using camp beds for occurrence in an area previously free of elevation from the floor. the disease. Control of case Additional sources of information Treatment is generally doxycycline or • Bell, D 1995, Tropical Medicine, 4th chloramphenicol. Consult the current edn, Blackwell Science. version of Therapeutic guidelines: • Odorico, D, Graves, S, Currie, B, antibiotic (Therapeutic Guidelines Catmull, J, Zoltan, N, Ellis, S, Wang, L Limited). and Miller, D 1998, ‘New Oriental In severe disease, consultation with an tsutsugamushi Strain from Scrub infectious diseases specialist is Typhus in Australia’. Emerging recommended. Infectious Diseases, vol. 4, no. 4. Control of contacts Consider active case finding if other people were exposed to the same setting as the case such as a camping holiday or military exercise. Control of environment Not applicable. The mites themselves act as reservoirs so no immediate effect is achieved by rodent control. Special settings Not applicable. The blue book: Guidelines for the control of infectious diseases 181

Ringworm or tinea (head), (body), tinea pedis (feet), tinea unguium (nails)

Victorian statutory requirement Method of diagnosis Tinea unguium occurs commonly but Notification is not required. Diagnosis can be made by microscopic there are low rates of transmission, even examination of material from the affected to close family associates. It is spread by School exclusion: readmit the day after area or by fungal culture. direct contact with skin or nail lesions of appropriate treatment has commenced. infected persons or indirectly through Infectious agent Incubation period contact with contaminated floors or The incubation period differs: Microsporum spp. includes Microsporum showers. canis as the primary causative agent in • tinea corporis has an incubation period Reservoir Australia of tinea capitis and corporis. of four to ten days Reservoirs for tinea are: Trichophyton spp. also cause disease for • tinea capitis has an incubation period example T. rubrum, T.mentagrophytes and of 10–14 days • tinea capitis: humans and animals Epidermophyton floccosum. including dogs, cats and cattle • the incubation period of tinea pedis • tinea corporis: humans, soil and Identification and tinea unguium is probably weeks animals including cattle, kittens, Clinical features but exact limits are unknown. puppies, guinea pigs, mice and horses The clinical features of tinea infections Public health significance are those of superficial fungal infection of • tinea pedis: humans and occurrence the skin, nails or hair: • tinea unguium: humans and rarely Tinea capitis mainly affects children. • tinea capitis results in a small papule animals or soil. M. canis is usually contracted from that spreads peripherally leaving fine, infected kittens or puppies. Mode of transmission scaly patches of temporary baldness. Direct transmission occurs through Infected hairs become brittle and The highly contagious M. audouinii human to human contact, for example break off easily. spreads from person to person and does not occur in Australia. T. rubrum and T.mentagrophytes. Animal- • tinea corporis appears as a flat, red, to-human contact also occurs, for ring-shaped lesion of the skin. It is Tinea capitis may extend to tinea example M. canis and T. verrucosum. usually dry and scaly or moist and corporis. It occurs worldwide. Tinea can be transmitted indirectly crusted but sometimes contains fluid Tinea corporis occurs worldwide and through contaminated soil, for example M. or pus. The lesion tends to heal relatively frequent. Males are infected gypseum. centrally. more than females. Infection can occur • tinea pedis is commonly known as from direct or indirect contact with skin Period of communicability ‘athlete’s foot’. It occurs as itchy, and scalp lesions of infected persons or The fungus persists on contaminated scaling, cracking of the skin or blisters animals. materials as long as lesions or animal hair harbour viable spores. containing a thin watery fluid. This Tinea pedis occurs in children and adults occurs commonly between the toes. and is spread by using communal Susceptibility and resistance • tinea unguium is a chronic fungal facilities such as showers at swimming Young children are particularly disease involving one or more nails of pools. Adults are affected more often susceptible to tinea capitis (Microsporum the hands or feet. The nail gradually than children and males more than canis). All ages are susceptible to thickens and becomes discoloured and females. Infection is more frequent and infections particularly those caused by brittle. Caseous-looking material forms severe in hot weather. Trichophyton spp. beneath the nail or the nail becomes chalky and disintegrates. 182 The blue book: Guidelines for the control of infectious diseases

Susceptibility to tinea corporis is • for tinea capitis oral griseofulvin is the widespread. It is aggravated by friction treatment of choice for resistant and excessive perspiration in axillary and infection, for example T. tonsurans. inguinal regions, and when environmental Topical anti-fungal medication may be temperatures and humidity are high. used concurrently Susceptibility is variable for tinea pedis • for tinea pedis topical fungicides are and infection may be inapparent. recommended but oral griseofulvin Repeated attacks are frequent. may be indicated in severe protracted An injury to the nail predisposes to tinea disease. Feet should be kept dry as unguium infection. Reinfection is possible and exposed to air by wearing frequent. sandals. Socks of heavily infected individuals should be boiled or Control measures discarded to prevent reinfection Preventive measures • for tinea unguium oral terbinafine Measures differ according to cause: should be given daily for six weeks for • for tinea capitis parents should be finger nails and twelve weeks for toe educated about modes of spread from nails. infected children and animals Consult the current version of • for tinea corporis shower bases, mats Therapeutic guidelines: antibiotic and floors adjacent to showers should (Therapeutic Guidelines Limited). be disinfected. Infected animals should Note: M. canis infection is self-limiting in be avoided children before puberty and griseofulvin • for tinea pedis gymnasiums, showers may not be necessary. Consult a and similar sources of infection should specialist about treatment. be thoroughly cleaned and washed. Control of contacts Shower areas should be frequently Investigate household contacts, pets and hosed and rapidly drained. Users of farm animals for evidence of infection. such areas should be encouraged to Treat infected contacts, human or animal. carefully dry (and perhaps powder) Control of environment between their toes. See Preventative measures, above. Control of case Control depends on the cause: Outbreak measures • for tinea corporis infected children Children and parents should be educated should be excluded from schools and about modes of spread, prevention and swimming pools until at least 24 hours the necessity of maintaining a high following the commencement of standard of personal hygiene. In case of appropriate treatment. It can be epidemics, consider examination of all treated effectively with topical children to identify cases. Disinfect medications contaminated articles. Ringworm (tinea) information sheet

What is ringworm? Ringworm of the foot (commonly known Further information Ringworm is a fungal infection that can as tinea or athlete’s foot) - The • Your local doctor characteristics of this common condition affect any part of the body. • Better Health Channel, are itchy scaling or cracking of the skin, www.betterhealth.vic.gov.au How do you get ringworm? especially between the toes, or blisters Ringworm is spread by direct and containing a thin watery fluid. • Victorian Department of Human indirect contact with humans, animals, Services, 1300 651 160 Ringworm of the nail - This condition and soil. tends to be a long term fungal disease Humans get infections through skin and and is difficult to treat. It usually affects scalp lesions of infected persons, one or more nails of the hands or feet. contaminated clothing, bath mats, The nail gradually thickens and becomes towels, floors and showers. discoloured and brittle. Cheesy-looking Animals get infections through cats, material forms beneath the nail, or the dogs, mice, and guinea pigs. Cattle and nail becomes chalky and disintegrates. horses may be infected. How do you control ringworm? How long is the incubation Seek medical advice to confirm diagnosis period? and receive appropriate treatment. The incubation period lasts from one to Exclude infected persons from three weeks. It varies with the site of communal swimming and bathing infection. facilities until appropriate treatment has commenced. How do you recognise Maintain hygiene by regular, thorough ringworm? bathing with soap and water and special Ringworm of the skin - This appears as a attention to drying moist areas. flat, spreading, circular lesion with a reddish outer edge. It is usually dry and • Do not share clothing or personal scaly or moist and crusted, but it may linen. contain fluid or pus. Single or multiple • Frequently launder clothing and linen in rings may appear. The centre of the hot water. patch may appear to be healing. • Wash pets with anti-fungal solution. Ringworm of the scalp and beard - This • Dry carefully between toes. condition begins as a small . It spreads outward leaving fine, scaly patches of temporary baldness. Infected hairs become brittle and break off easily.

Department of Human Services 184 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 185

Ross River virus disease

Arboviruses are viruses which are spread Identification Incubation period by the bite of arthropods, particularly Clinical features The incubation period is usually three to mosquitoes. They are divided into Pyrexia and other constitutional eleven days. alphaviruses and flaviviruses. symptoms are usually slight. A rash can Public health significance Three infective alphaviruses include Ross occur up to two weeks before or after and occurrence River, Barmah Forest and Sindbis viruses. other symptoms. It can be absent in about one–third of cases. The rash is Infection is subclinical in up to 60% of These all have the capacity to cause a variable in distribution, character and cases. Clinical features of infection are similar disease in humans characterised duration and may be associated with rare before puberty after which the by fever, joint involvement and a rash. buccal and palatal enanthems. disease has a similar pattern at all ages. Molecular studies of epidemiologically Rheumatic symptoms are present in The disease can cause incapacity and distinct isolates of Ross River and Sindbis most patients except for the few who inability to work for two to three months. viruses have shown changes in isolates present with rash alone: these consist of About one quarter of patients have from different areas (distinct topotypes). arthritis or arthralgia primarily affecting rheumatic symptoms which persist for a This may explain varying disease the wrist, knee, ankle and small joints of year or more. patterns which sometimes occur in the extremities. Prolonged symptoms are RRV disease is the commonest and most certain geographic locations and the common. In some cases there may be widespread arboviral disease in Australia, differing transmissibility of some strains remissions and exacerbations of sometimes thousands of clinical cases by different vector mosquitoes. decreasing intensity for years. Cervical occur in epidemics. Disease notifications Victorian statutory requirement lymphadenopathy occurs frequently and in Australia average about 4800 per year. Ross River virus infection (Group B paraesthesiae and tenderness of the Major outbreaks have occurred in all disease) requires notification within five palms and soles are present in a small parts of Australia. These occur chiefly in days of diagnosis. percentage of cases. the period from January to May. RRV has been detected and probably transmitted School exclusion is not required. Method of diagnosis Serology shows a significant rise in to humans in most major metropolitan Infectious agent antibody titre to RRV. The virus may be areas of Australia including Perth, First isolated in 1959 from Aedes vigilax isolated from the blood of acutely ill Brisbane, Sydney and Melbourne. In mosquitoes collected near the Ross River patients. Virological tests are necessary 1993, 1216 cases of RRV disease were in Townsville, the causative role of Ross to distinguish RRV disease from other notified in Victoria. Epidemics usually River virus (RRV) was confirmed in 1971 causes of arthritis. In the event of a local follow heavy rains or after high tides by its isolation from the blood of an outbreak clinical diagnosis may be which inundate salt marshes or coastal indigenous child with the disease. Some sufficient, but outbreaks of RRV disease wetlands. Sporadic cases occur in Aedes species have recently been sometimes occur concurrently with BFV mainland and coastal regions of Australia renamed Ochlerotatus spp. mosquitoes. disease making diagnosis difficult. and Papua New Guinea at other times of the year. In 1979, a major outbreak of Laboratory evidence requires one of the RRV disease which was probably following: exported from Australia occurred in Fiji • isolation of RRV from clinical material and spread to other Pacific islands, • detection of RRV by nucleic acid including Tonga and the Cook Islands. testing • a significant rise in IgG to RRV • detection of RRV-specific IgM. 186 The blue book: Guidelines for the control of infectious diseases

Reservoir Susceptibility and resistance Outbreak measures The virus is maintained in a primary Infection with the RRV confers lifelong Conduct a community survey to mosquito–mammal cycle involving immunity. determine the species of the vector macropods (particularly the Western mosquito involved. Identify their breeding Grey kangaroo) and possibly other Control measures places and promote their elimination. Preventive measures marsupials and wild rodents. A Use mosquito repellents for persons RRV infection can be prevented by: man–mosquito cycle may occur in exposed to bites because of their explosive outbreaks. Horses can act as • mosquito control measures occupation, or other reasons. amplifier hosts and appear to develop • personal protection measures such as joint and nervous system disease after Identify the infection among animal wearing long sleeves and mosquito reservoirs, for example kangaroos, small infection with RRV. Fruit bats might act repellents as vertebrate hosts in some areas. marsupials, farm and domestic animals. • avoidance of mosquito-prone areas Vertical transmission in desiccation- International measures resistant eggs of Ochlerotatus spp. and exposure during biting times at dusk and dawn. Airport vector control in Australia and mosquitoes may be a mechanism to Papua New Guinea may be necessary to enable the virus to persist in the Control of case prevent spread from endemic areas to environment for long periods. This could Second attacks are unknown. Treatment other countries where local vectors such explain the rapid appearance of cases of is symptomatic with rest advisable in the as Aedes polynesiensis may transmit the RRV disease after heavy rains. RRV is acute stages of the disease. There is no disease. endemic throughout Australia, Papua vaccine currently available commercially New Guinea, adjacent Indonesia and the to protect against RRV disease. Solomon islands Control of contacts Mode of transmission Unreported or undiagnosed cases should be sought in the region where the patient RRV is transmitted by mosquitoes. Culex had been staying during the incubation annulirostris is the major vector in inland period of their illness. All family members areas whilst Ochlerotatus vigilax in New should be questioned about symptoms South Wales and Ochlerotatus and evaluated serologically if necessary. camptorhynchus in southern parts of Victoria and Tasmania are the vectors in Control of environment coastal regions. To reduce or prevent virus transmission, interruption of human-mosquito contact Period of communicability is required by: There is no evidence of transmission • suppression of the vector mosquito from person to person. population • avoidance of vector contact through personal protection and education. The blue book: Guidelines for the control of infectious diseases 187

Rotaviral gastroenteritis

Victorian statutory requirement Reservoir Control of environment Isolated cases are not notifiable. Humans. Rigorous attention to clean-up procedures and personal and home School exclusion: exclude from school or Mode of transmission hygiene is essential to prevent further child care centre until at least 48 hours Rotavirus is transmitted predominantly transmission. after symptoms have ceased. via the faecal-oral route. Rotavirus has Infectious agent been detected in respiratory secretions. Outbreak measures An outbreak is defined as two or more Rotavirus, predominantly Group A, is the Because the virus is stable in the related cases of gastroenteritis. The causative agent. environment transmission can occur through ingestion of contaminated water primary aim is to prevent further disease Identification or food and contact with contaminated by identifying the source, cleaning Clinical features surfaces. contaminated environments and isolating The disease is characterised by vomiting cases. Period of communicability and watery diarrhoea lasting for three to Special settings Rotavirus is communicable during the eight days. Fever and abdominal pain Specific protocols for the management of acute stage of disease and while viral occur frequently. Treatment is outbreaks in special settings are shedding continues. Excretion of virus for symptomatic. Maintenance of hydration available from the Communicable greater than 30 days has been is the most important measure. Diseases Section of the Department of documented. Method of diagnosis Human Services, phone 9637 4126. Diagnosis may be made by rapid antigen Susceptibility and resistance Additional sources of information detection of rotavirus in stool specimens. Everyone is susceptible to infection. • Centers for Disease Control and Strains may be further characterised by Immunity after infection is incomplete, Prevention, Atlanta USA, Viral enzyme immunoassay or reverse but repeat infections tend to be less gastroenteritis, http://www.cdc.gov/ transcriptase polymerase chain reaction. severe than the original infection. ncidod Stools for these tests should be collected in the acute phase of illness. Control measures Preventive measures Incubation period Prevention is primarily through good The incubation period is approximately personal, food and home hygiene. 24–72 hours. Control of case Public health significance Provide advice regarding personal and occurrence hygiene, exclusion from work or school or Disease usually occurs in infants and child care and attempt to identify source young children, particularly under two of infection. Health care workers and years of age. Adults can also be infected food handlers should be excluded from although their resultant disease tends to work until at least 48 hours after be mild. In temperate climates it is more diarrhoea has ceased. common in the winter months. Rotavirus Control of contacts gastroenteritis is the leading cause of Identify whether any contacts are ill. infant viral gastroenteritis worldwide. The Provide advice about strict personal, food cost of managing rotavirus disease in and home hygiene. Australia is estimated at $26 million annually. 188 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 189

Rubella (German measles)

Victorian statutory requirement Differential diagnosis includes measles, Routine serological testing of reported Rubella and congenital rubella syndrome human parvovirus (‘slapped cheek’) clinical cases of rubella in Victoria has (Group B disease) must be notified in infection, human herpesvirus 6 (roseola) revealed that only a small proportion of writing within five days of diagnosis. infection and a large number of other these cases can be confirmed in the rashes of varied aetiology. laboratory. The remainder are likely to be School exclusion: excluded until fully due to other causes. recovered or at least four days after the Method of diagnosis onset of the rash. Clinical diagnosis should be confirmed Unimmunised travellers and their by one or more of the following: unimmunised contacts remain at risk of Infectious agent • demonstration of rubella-specific IgM infection. Rubella virus of the Togaviridae family is antibody, except following rubella Congenital rubella syndrome (CRS) was a the infective agent. immunisation major cause of congenital abnormalities Identification • fourfold or greater rise in rubella including deafness prior to the infant Clinical features antibody titre between acute and immunisation program. Although CRS is Rubella is a mild febrile viral illness convalescent-phase sera obtained at • now rare, the risk of infection remains for characterised by a diffuse punctate and least two weeks apart unimmunised pregnant women. Such maculopapular rash. Children usually women have been infected primarily by • isolation of rubella virus from a clinical experience few or no constitutional persons who have not been included in specimen. symptoms but adults may experience a rubella vaccine programs. one to five day prodrome of low-grade Consider also testing for other similar Reservoir fever, headache, malaise, mild coryza such as measles and human Humans. and conjunctivitis. Postauricular, occipital parvovirus. and posterior cervical lymphadenopathy Incubation period Mode of transmission is common and precedes the rash by five The incubation period is usually 14 to 17 Rubella is transmitted by droplet spread to ten days. days. It ranges from 14 to 21 days. or direct contact with infectious patients. Complications include arthralgia and less Infants with CRS shed the rubella virus in commonly arthritis, particularly among Public health significance their nose, pharyngeal secretions and adult females. Encephalitis is a rare and occurrence urine for months or even years. complication. Rubella occurs worldwide and is universally endemic except in remote Congenital rubella syndrome (CRS) Period of communicability and isolated communities. It is most occurs in less than 25% of infants born to Rubella is communicable approximately prevalent in winter and spring. women who acquire rubella during the one week before and for at least four first trimester of pregnancy. The risk of a A combined measles-mumps vaccine days after the onset of the rash. single congenital defect falls to was first added to the routine childhood CRS infants may shed the virus for approximately 10–20% by the 16th week immunisation schedule in 1983. months or longer after birth. of pregnancy. Defects are rare when the Although this has clearly led to a maternal infection occurs after the 20th dramatic reduction in the number of week of gestation. reported cases the epidemiology of rubella infection in Australia is not clear because of the acceptance of clinical diagnoses without laboratory confirmation. 190 The blue book: Guidelines for the control of infectious diseases

Susceptibility and resistance Control of case Immunoglobulin should be considered Immunity after natural disease is usually There is no specific treatment. after exposure to rubella in early life long. Immunity after vaccination is The case should be excluded from pregnancy. It may not prevent infection long term and usually lifelong, although school and childcare for at least four days or viraemia, but may modify reinfection of vaccinees has been after onset of the rash. Adults should not abnormalities in the baby. observed. go to work for the same period of time. Control of environment Passive maternal immunity is acquired Patients with rubella should avoid Not applicable. transplacentally. Infants born to immune contact with other people while Outbreak measures mothers are ordinarily protected for six to infectious, particularly pregnant women. nine months depending on the amount All suspected outbreaks should be If a person with suspected rubella is of maternal antibodies transferred. reported promptly to the Department of pregnant, the diagnosis should be Human Services. confirmed serologically and the patient Control measures Mass immunisation may be referred to a specialist obstetrician for Preventive measures recommended during an outbreak of advice, taking care not to expose other MMR vaccine is recommended in the rubella in a school regardless of immune pregnant women to possible infection in ASVS for all infants at the age of 12 status. months and at again at four years of age. the process. Women of childbearing age should be Control of contacts tested for immunity to rubella prior to School contacts should not be excluded pregnancy if possible. All non-pregnant from school regardless of immunisation seronegative women should be offered status. rubella vaccine. Although immunisation is generally Women receiving rubella vaccine should recommended for non-immune contacts be instructed to avoid pregnancy for 28 (except pregnant women) it is unlikely to days after vaccination. Inadvertent reduce the risk of infection or illness. rubella vaccination during pregnancy has Immunoglobulin is not generally not been associated with any CRS-like recommended, except for pregnant defects; it is not necessary to consider contacts. termination. Pregnant women in whom immunity to Women attending for antenatal care who rubella has not been confirmed for the are unaware of their immune status current pregnancy and who may have should be tested for rubella antibodies been exposed to rubella must be and if negative, be vaccinated investigated serologically. This should immediately post partum. occur irrespective of a history of vaccination, clinical rubella or previous All health care workers should receive positive rubella antibody. MMR vaccine if not immune. The blue book: Guidelines for the control of infectious diseases 191

Salmonellosis

Victorian statutory requirement Public health significance foods also occurs. This occurs Salmonellosis (Group B disease) must be and occurrence particularly with: notified in writing within five days of Salmonella infection occurs worldwide • raw and undercooked eggs and egg diagnosis. and only a small proportion of cases are products detected and reported. The incidence of Laboratories are required to notify • raw milk and raw milk products Salmonellae isolated from food or water. infection is highest in infants and young children. Mortality is low however it may • poultry and poultry products School exclusion: exclude cases from be increased in the elderly and • raw red meats child care and school until after the immunocompromised people. • unwashed salads, fruits and diarrhoea has ceased. Salmonellosis may incur significant social vegetables, grains, seeds and nuts Infectious agent and economic costs due to lost • some shellfish and filter feeders such Approximately 2000 known serotypes productivity and the impact on industry as oysters exist of Salmonella spp, a small number and agriculture. of which usually account for the majority There are approximately 1000 cases of Period of communicability of infections. salmonellosis reported in Victoria each Salmonellosis is communicable through year. The most common serovar is the course of infection, usually several Identification S. typhimurium. The majority of cases are days to several weeks. One per cent of Clinical features sporadic, but outbreaks in institutions infected adults and five per cent of Salmonellosis commonly presents as an and child care centres and those children under the age of five years acute gastroenteritis with fever, vomiting, associated with retail food premises are excrete the organism for more than one nausea, abdominal pain, headache and not uncommon. The emergence of year. Antibiotics given in the acute illness diarrhoea. Dehydration may occur, strains resistant to single or multiple can prolong the carrier state. especially among infants and the elderly. antibiotics is of increasing concern Infection may also present as septicaemia worldwide. Susceptibility and resistance and occasionally may be localised in other Susceptibility may be increased by some body tissues resulting in endocarditis, Reservoir medical conditions and treatments pneumonia, septic arthritis, cholecystitis Domestic and wild animals including including immunosuppressant therapy, and abscesses. Symptoms usually last poultry and reptiles act as reservoirs. prior or concurrent broad-spectrum three to five days. Patients and convalescent carriers antibiotic therapy, gastrointestinal surgery, Method of diagnosis including mild and unrecognised cases antacid use, achlorhydria and Infection is diagnosed by isolation of can also act as reservoirs. malnutrition. Salmonella spp. from faeces, blood or Mode of transmission Severity of the disease varies with: other clinical specimen. Transmission is via person to person or • the serotype animal to person spread via the faecal- Incubation period • the numbers of organisms ingested The incubation period is usually 6–72 oral route. • the vehicle of transmission hours with an average of 12–36 hours. Ingestion of the organisms via contaminated or improperly cooked • host factors. 192 The blue book: Guidelines for the control of infectious diseases

Control measures Use standard enteric precautions when the Microbiological Diagnostic Preventive measures handling faeces, contaminated clothing Laboratory. Staff of the Communicable Thoroughly cook all food derived from and bed linen from hospitalised patients. Diseases Section, the Department’s animals sources, particularly poultry, Exclude symptomatic cases from food Food Safety Unit, and Local Government pork, egg products and meat dishes. handling and direct care of children, the Environmental Health Units usually Inadequate temperature control and elderly and immunosuppressed patients conduct environmental investigations. incorrect storage of food during and after until after the diarrhoea has ceased. Refer to the Department’s Guidelines for the cooking process facilitates bacterial Children are excluded from school and the investigation of gastrointestinal illness multiplication and are important risk child care until diarrhoea has ceased. for specific details. factors. Instruct asymptomatic individuals in International measures • Avoid recontamination from raw food strict personal hygiene. Stress proper International outbreaks are increasingly within the kitchen or refrigerator, after hand washing. cooking is completed. being recognised, primarily due to the Control of contacts increased dissemination of food and • Emphasise the importance of Consider the diagnosis in symptomatic agricultural products worldwide. refrigerating food and maintaining a contacts. Active case finding is not Investigation of imported products sanitary kitchen. routinely undertaken in sporadic cases. should be coordinated through Food • Avoid consuming raw or incompletely Control of environment Standards Australia New Zealand. cooked eggs, or using dirty or cracked Sources of contamination such as use of eggs. uncooked products and inadequate • Pasteurise all milk and egg products. cooking should be investigated. Attention should be paid to environmental • Educate food handlers on the cleaning, particularly in institutions, child importance of hand washing and care centres and food premises. separating raw and cooked foods. • Inspect and supervise abattoirs, Outbreak measures butcher shops, food-processing plants Two or more related cases of and egg-grading stations. gastroenteritis are suggestive of an Control of case outbreak and should be reported to the Treatment is supportive and antibiotics are Department of Human Services not indicated in uncomplicated immediately. The aims of an outbreak gastroenteritis as they may prolong the investigation are to rapidly identify the carrier state and promote antibiotic source and prevent further cases. resistance. The exceptions are patients at Epidemiological, environmental and high risk of more severe disease including laboratory investigations will be infants under two months of age, the elderly implemented immediately. and immunocompromised (particularly Stools should be collected from cases those with HIV), and food handlers who are and attempts made to identify a chronic carriers. For systemic disease, the common source by obtaining food choice of antibiotic should be based on the histories and potentially relevant antibiograms of the relevant serovar and environmental exposures. Any implicated local antibiotic guidelines. foods should be retained for analysis at The blue book: Guidelines for the control of infectious diseases 193

Scabies

Victorian statutory requirement Immunosuppressed people, those living Symptoms develop much more quickly if Notification is not required. in institutions and the elderly may also a person is re-exposed, often within one show a clinical pattern of infestation to four days. School exclusion: exclude until the day similar to that in infants. after appropriate treatment has The incubation period may be shorter if commenced. Itching varies from person to person but infestation is acquired from a person may be severe. It tends to be more with crusted (Norwegian) scabies. In this Infectious agent marked at night or after a hot bath. case it is between 10 to 14 days. The Sarcoptes scabiei mite is a tiny eight Scratching may lead to secondary legged creature barely visible to the bacterial infections. Public health significance and naked eye. Females are 0.3 to 0.4mm occurrence Crusted (Norwegian) scabies long and 0.25 to 0.35 mm wide. Males Scabies occurs worldwide regardless of This is a particularly virulent infestation are less than half the size of the female. age, sex, race, socio-economic status or that can occur in the elderly, debilitated standards of personal hygiene. Scabies life cycle or immunosuppressed patients including The mite undergoes four stages in its life those with HIV infection. These patients Cyclical epidemics occur at intervals of cycle: egg, larva, nymph and adult. The are highly infective and difficult to treat. 10 to 15 years. female mite burrows into the skin, lays Large areas of the body may appear Outbreaks may occur in childcare eggs, larvae travel to the skin surface scaly and crusted with thousands of centres and kindergartens, and are where they moult into nymphs and mites and eggs. Treatment applied frequently reported in nursing homes and become adult mites. The period from directly to the skin such as creams and institutions. Scabies is more likely to fertilization to adult mite ranges from 10 lotions may not penetrate the crusted spread in situations of overcrowding. to 14 days. Female mites live about two thickened skin and result in treatment months, laying three eggs a day and failure. Reservoir travel up to three centimetres a minute. Humans are the primary reservoir. Other Crusted scabies may be misdiagnosed species of mite from animals or birds can as or eczema. Identification also live on humans but do not Clinical features Method of diagnosis reproduce in the skin. Scabies is a highly contagious parasitic Diagnosis is commonly made clinically skin infestation characterised by thin, by examining the burrows or rash. The Mode of transmission slightly elevated, wavy grey-white diagnosis may be confirmed by scraping Scabies is transmitted by: burrows that contain the mites and eggs. the burrows with a needle or scalpel • skin contact with an infected person Multiple papules and vesicles soon blade and identifying the mites or eggs • contact with towels, bedclothes and appear. under a microscope. A negative result on under-garments if these have been skin scraping is not always conclusive as The most common sites for burrows are contaminated by infested persons the infested person may have few mites between the fingers and toes, anterior within the last four to five days. surfaces of the wrists and elbows, axillae, (on average 10 to 15) and these can The mites cannot jump or fly. Adult lower abdomen, beneath female breasts easily be missed on skin scraping. scabies mites may survive off the skin for and genitalia. The face, head, palms and Incubation period up to 48 hours in room conditions. soles are seldom involved in adults but in It may take two to six weeks before infants any area of skin may be infected. itching occurs in a person not previously exposed to scabies. 194 The blue book: Guidelines for the control of infectious diseases

Period of communicability For moderate and severe infections, treatment. Treat all those who have had Scabies is communicable until mites and repeat scabicide treatment in 14 days. close skin to skin contact with the case, eggs are destroyed by treatment, usually Infested persons should be excluded this includes family members, playmates two courses one week apart. Itching may from school or workplace until the day and staff. Treatment should occur persist for two or more weeks after following the first application of simultaneously to reduce the risk of successful eradication of the mite. appropriate treatment. reinfestation. Generally, prolonged close contact is required for transmission. Susceptibility and resistance For hospitalised patients or patients in Nursing homes, aged care and other Fewer mites succeed in establishing nursing homes contact isolation should residential facilities themselves in persons previously be used until appropriate treatment has See below, Guide to scabies infested than in those with no prior commenced. In order to prevent management in residential care facilities. exposure. Diminished resistance to nosocomial infection, affected staff infestation is also suggested by the should be excluded until appropriate Additional sources of information treatment has commenced. observation that immunologically • Centres for Disease Control and compromised persons are most Control of contacts Prevention, Scabies fact sheet, susceptible to severe infestations. Investigate contacts and source of http://www.cdc.gov/ncidod infestation. Control measures • Centres for Disease Control and Preventive measures Treat all household contacts, sexual Prevention 1988, ‘Epidemiologic notes Educate the public about the mode of contacts, and those considered ‘at risk’ and reports scabies in health-care spread, early diagnosis and treatment, by virtue of close contact in nursing facilities – Iowa’, MMR Weekly, vol. 37, and promote good personal hygiene. homes and institutions simultaneously. no. 11, pp. 178–9. Control of case Control of environment • Degelau J 1992, ‘Scabies in long-term For simple scabies the usual treatment is Clothing, towels and bedclothes used by care facilities’, Infection Control and permethrin applied topically to the whole the infested person in the 48 hours prior to Hospital Epidemiology, vol. 13, no. 7. body including face and hair (avoid eyes treatment should be laundered using the pp 421–425. hot cycle or dry cleaned. Alternatively, and mucous membranes) and left • Lemmon, J 1998, ‘Scabies outbreak items may be placed in a plastic bag and overnight, or benzyl benzoate 25% among nursing staff’, 1998 Nursing sealed for one week before laundering as emulsion applied topically, including face monograph, St Vincents Hospital & mite cannot survive lengthy periods off the and hair (avoid eyes and mucous Sacred Heart Hospice NSW, human body. membranes) and left for 24 hours. http://www.clininfo.health.nsw.gov.au For children less than two months of age Outbreak measures sulfur 5% cream or crotamiton 10% cream Special settings are alternatives (see the current edition School and childcare facilities of Therapeutic guidelines: antibiotic). Exclude the case until the day after For crusted (Norwegian) scabies, the appropriate treatment has been given. addition of oral ivermectin may also be Advise staff and parents of other children considered. Seek specialist infectious who may have had direct contact with disease or dermatological advice. the infested person and may require Scabies information sheet

What is scabies? How do you get scabies? How long does it take until Scabies is an infestation caused by the By direct, prolonged, skin-to-skin contact symptoms start? microscopic mite Sarcoptes scabiei. It is with a person already infested with It may take 4 to 6 weeks for symptoms to found worldwide and affects people of all scabies. Contact must be prolonged (a develop in people who haven’t had races and social classes. Scabies quick handshake or hug will usually not scabies before. People who have had spreads rapidly in conditions where there spread infestation). Infestation is easily scabies before usually develop is frequent skin-to-skin contact between spread to sexual partners and household symptoms much more quickly if they are people, such as aged care facilities, members. Infestation may also occur by exposed again, usually within one to four childcare centres and residential sharing clothing, towels, and bedding. days. facilities. Anyone can get scabies regardless of age, sex, race or standards of personal How long are people with The female mite, which is only a few scabies infectious to others? millimetres long, burrows into the top hygiene. People with scabies can pass on the layer of the skin where she lays her eggs. Did my pet spread scabies to scabies mite until the day after they have The eggs hatch into larvae after 10 to 14 me? commenced their treatment for scabies. days and travel back up to the surface of No. Pets become infested with a different The scabies mite can live for two to three the skin. Female mites live for about two kind of scabies mite. If your pet is days on the clothes, bed linen and other months, laying three eggs a day and infested with scabies, (also called personal items of people who have travel up to three centimetres a minute. mange) and they have close contact with scabies. you, the mite can get under your skin and What are the symptoms of How is scabies diagnosed? scabies? cause itching and skin irritation. Diagnosis is commonly made by The main symptoms are: However, the mite dies in a couple of days and does not reproduce. The mites examining the characteristic burrows or • pimple-like irritations, burrows or rash may cause you to itch for several days rash. The diagnosis may be confirmed by of the skin, especially the webbing but you do not need to be treated with scraping the burrows with a needle or between the fingers; the skin folds on special medication to kill the mites. Until scalpel blade and identifying the mites or the wrist, elbow, or knee; the penis, the your pet is successfully treated, mites eggs under a microscope. A negative breast, or shoulder blades. can continue to burrow into your skin result on skin scraping is not always • intense itching, especially at night and and cause you to have symptoms. conclusive as the infested person may over most of the body. have few mites (on average 10 to 15) and Who is at risk for severe these can easily be missed on skin • sores on the body caused by infestation? scraping. scratching. These sores can People with weakened immune systems sometimes become infected by and the elderly are at risk for a more bacteria. severe form of scabies, called crusted or Norwegian scabies.

Department of Human Services Can scabies be treated? The lotions or creams are applied to the As the scabies mite can live on the bed Yes. A number of effective anti-scabies whole body from the neck to the toes. linen, clothes, towels and other personal lotions or creams are available from your The treatment may also need to be used by the person with scabies prior to local pharmacist. A prescription from applied to the face and scalp if these starting their treatment, these items your doctor is not required. areas are clearly involved. Avoid contact should be machine washed in hot water. with the eyes, nose and mouth. Blankets can be dry cleaned or placed in Recommended treatments include a tumble dryer on a hot setting for half an permethrin preparations (e.g. Lyclear People will no longer be infectious within hour. Alternatively, scabies mites can be cream or Quellada lotion) or benzyl 24 hours of treatment, but it can take up killed by sealing these items in a plastic benzoate 25% preparations (e.g. Ascabiol, to two months until the skin lesions and bag for one week before laundering, as Benzemul 25%). itch to disappear completely. the mite cannot survive lengthy periods Note that: A repeat treatment may be advised 14 off the human body. days after the first treatment, particularly • Lyclear cream or Quellada lotion should for moderate to severe infestations. not be used during pregnancy, Further information lactation, for children less than two or Antihistamines, calamine lotion and • Your local doctor in those with extensive dermatitis Eurax are sometimes useful to • Better Health Channel, counteract itchiness. Antibiotics may be • for children under 2 months of age www.betterhealth.vic.gov.au needed if there is secondary bacterial sulfur 5% cream or crotamiton 10% • Victorian Department of Human infection from scratching. cream (e.g. Eurax) are alternatives Services, 1300 651 160 • Ascabiol and Benzemul 25% What else should I do to stop preparations should be diluted for the spread of scabies? children less than 2 years of age (dilute Preventing the spread of scabies with 3 parts water) and for children 2 requires: to 12 years of age and adults with • maintaining good personal hygiene sensitive skin (dilute with equal parts water) • not sharing clothes, towels or bed linen with others • the anti-scabies preparations should be used according to the • excluding affected children from manufacturer’s directions school and child care centres until treatment has commenced • ensure that all household members are treated simultaneously. • limiting close physical contact with others until appropriate treatment has commenced. The blue book: Guidelines for the control of infectious diseases 197

Guide to scabies management in residential care facilities

Contact precautions should be employed When crusted (Norwegian) scabies is Scabies infection control for suspected cases until the diagnosis is suspected, a single oral dose of measures excluded by skin scraping, and, if ivermectin is often prescribed in addition Linen and bed linen should be hot confirmed, until the day after appropriate to the scabicide. Specialist infectious washed while the treatment application therapy has been commenced. As skin disease or dermatological advice should is on and linen used during the scraping is not always positive in true be sought. application period hot washed after the cases, therapy may need to be treatment is washed off. commenced if the clinical suspicion Treating contacts Clothes and towels used by the affected remains high. Close contacts without symptoms who have had recent close contact with persons in the 48 hours prior to Treating cases cases should be advised of their possible treatment should be machine washed in Residents and/or staff should be treated exposure to scabies and be treated hot water. Linen, blankets and clothing with Permethrin 5% cream (e.g. Lyclear, simultaneously as above, but with no can also be dry cleaned or placed in a Quellada) topically, to the whole body repeat treatment required. Close tumble dryer on a hot setting for half an including face, hair, behind ears and contacts include: hour, or sealed in a plastic bag for one week before laundering. fingernails (avoid eyes and mucous • residents with recent close contact, membranes), leave 8 to 12 hours (e.g. including those who share the same overnight) or Benzyl benzoate 25% room emulsion (e.g. Ascabiol, Benzemul 25%) topically, to the whole body including • family members and regular visitors face, hair, behind ears and fingernails with recent close contact with the (avoid eyes and mucous membranes), case leave for 24 hours. For adults with • staff members with recent close sensitive skin, dilute with equal parts contact, including staff handling water. Consult the current version of laundry items. Therapeutic guidelines: antibiotic Close contacts with symptoms (Therapeutic Guidelines Limited). consistent with scabies, such as itch or A repeat treatment is advised 14 days rash, should be treated as if they were a after the first treatment, particularly for case (see Treating cases, above). moderate to severe infestations. Any agency staff should be notified as Occasionally large nodular lesions they will also need treatment, especially (scabies nodules) can develop in the as many attend different health care elderly. These can remain itchy for facilities. If necessary notify the Agency in several months after successful order to trace staff. treatment. In these circumstances the Everyone identified as needing treatment use of topical steroids (e.g. Betnovate should ideally be treated within the same cream, Elecon cream) may be necessary. 24 to 48 hour period. Itch may persist for over 2 weeks after successful treatment and this does not signify treatment failure. 198 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 199

Severe acute respiratory syndrome (SARS)

Victorian statutory requirement Any specific testing for SARS should only • stool samples if diarrhoea is present SARS – CoV infection (Group A disease) be performed after consultation with the • serum for antibody titres and, where must be notified immediately by Communicable Diseases Section of the appropriate, convalescent serum for telephone or fax followed by written Department of Human Services (DHS), parallel testing. notification within five days. (see Guidance for recognition, investigation and infection control of Testing is only performed at the Victorian Infectious agent SARS and avian influenza, Infectious Diseases Reference SARS-associated coronavirus (SARS- http://www.health.gov.au/ Laboratory (VIDRL) and all tests should CoV). At that time the status of any outbreak be clearly labelled ‘For urgent SARS can be ascertained, the exposure and testing at VIDRL’. Identification epidemiological links clarified, the case Suspect case Clinical features may be notified, appropriate infection A person presenting after 1 November Severe Acute Respiratory Syndrome control processes confirmed, and 2002 with history of: (SARS) is a recently recognised lower suitable patient transfer arranged. respiratory tract infection. In the first • high fever (>38°C) AND week of illness the patient develops The testing algorithm for SARS is heavily • cough or breathing difficulty AND dependent upon the prevalence of the influenza-like symptoms, which include • one or more of the following exposures disease worldwide and locally, and this fever, malaise, myalgia, headache, and during the 10 days prior to onset of can be found on Department of Health rigors. No individual symptom or cluster symptoms: of symptoms has proven specific, and Ageing web site however a history of fever is the one http://www.health.gov.au – close contact with a person who is a suspect or probable case of SARS most frequently reported. The microbiological investigation of a The patient progresses to develop a possible SARS infected patient will – history of travel, to an area with cough (initially dry), dyspnoea and often include the concurrent testing for other recent local transmission of SARS diarrhoea (large volume and watery) more common and likely respiratory (http://www.health.gov.au) usually in the second week of illness, pathogens through normal means – residing in an area with recent local although these features may occur (sputum, blood, nasal swabs, urine) as transmission of SARS well as specific tests aimed to detect earlier. OR SARS-CoV. Severe cases progress to a rapidly A person with an unexplained acute The samples to be collected for SARS increasing respiratory distress and respiratory illness resulting in death after CoV specifically include: oxygen desaturation of which 1 November 2002, but on whom no approximately 20% require intensive care. • a left and right nasal swab and a autopsy has been performed AND one or Upper respiratory symptoms such as posterior pharyngeal wall swab all more of the following exposures during to and sore throat may occur but placed into the same viral transport 10 days prior to onset of symptoms: medium. These can have PCR testing are uncommon. • close contact with a person who is a for many different respiratory viruses Method of diagnosis and case suspect or probable case of SARS (respiratory multiplex) as well as for definition SARS-CoV if that is considered • history of travel to an area with recent appropriate. An alternative to this is a local transmission of SARS nasopharyngeal aspirate • residing in an area with recent local transmission of SARS 200 The blue book: Guidelines for the control of infectious diseases

Close contact: having cared for, lived A suspect case should be excluded if c)Virus isolation with, or had direct contact with they have had a mild self limiting illness • Isolation in cell culture of SARS-CoV respiratory secretions or body fluids of a however, persons are not to be from any specimen AND suspect or probable case of SARS. downgraded should signs of clinical • PCR confirmation using a validated illness remain. Probable case method. A suspect case with Laboratory confirmed SARS Reclassification of cases A person with symptoms and signs that • radiographic evidence of infiltrates A suspect case who, after investigation, are clinically suggestive of SARS consistent with pneumonia or fulfils the probable case definition should respiratory distress syndrome (RDS) on AND be reclassified as ‘probable’. A suspect chest X-ray (CXR) With positive laboratory findings for case with a normal CXR should be OR SARS-CoV, based on one or more of the treated, as deemed appropriate, and A suspect case with following diagnostic criteria: monitored for 7 days. Those cases in a)PCR positive for SARS-CoV whom recovery is inadequate should be • autopsy findings consistent with the re-evaluated by CXR. pathology of RDS without an PCR positive using a validated method identifiable cause. from: A suspect case who dies, on whom no autopsy is conducted, should remain Exclusion criteria • at least two different clinical classified as ‘suspect’. However, if this A probable or suspect case should be specimens (e.g. nasopharyngeal and case is identified as being part of a chain excluded if: stool) OR of transmission of SARS, the case should 1. No convincing possibility of exposure • the same clinical specimen collected be reclassified as ‘probable’. If an Visited a SARS affected area, but was in on two or more occasions during the autopsy is conducted and no transit for less than 8 hours (in total, if course of the illness (e.g. sequential pathological evidence of RDS is found, multiple stopovers) and remained within nasopharyngeal aspirates) OR the case should be ‘discarded’. the airport. • two different assays or repeat PCR Maintaining vigilance and SARS alert 2.An alternative diagnosis is made using a new RNA extract from the clusters original clinical sample on each If SARS does reemerge, it is unlikely but e.g. a clinical diagnosis of probable occasion of testing. not impossible, that the first place it is bacterial pneumonia, which could be recognised will be Australia. The most defined by X-ray findings of lobar b)Seroconversion by ELISA or IFA likely scenario is that this will occur in consolidation and clinical response to • Negative antibody test on acute serum another country or countries (particularly antibiotics. A case initially classified as followed by positive antibody test on Southern China, the source of the suspect or probable, for whom an convalescent phase serum tested in original outbreak), providing time for alternative diagnosis can fully explain the parallel OR Australia to institute targeted surveillance illness, should be discarded after • Fourfold or greater rise in antibody titre and investigation of illness in travelers carefully considering the possibility of co- between acute and convalescent from defined outbreak areas, as was infection. phase sera tested in parallel. undertaken in the initial outbreak period. The blue book: Guidelines for the control of infectious diseases 201

Although both WHO and Australian health b) One or more symptoms of lower The pathogen emerged out of Southern authorities regard Australia as a low respiratory tract illness (cough, difficulty China creating a local outbreak of likelihood country to first recognise a new breathing, atypical pneumonia and subsequent SARS outbreak, a cautious approach is shortness of breath) infection of international travellers being taken. Maintaining vigilance for SARS resulted in the importation of possible (www.health.gov.au/sars) is a surveillance AND SARS cases to 29 other countries around protocol that seeks to ensure that c) Radiographic evidence of lung the world. Hong Kong, Hanoi, Singapore Australian health authorities will detect any infiltrates consistent with pneumonia or and Toronto received such infected new SARS outbreak by the detection of acute respiratory distress syndrome travellers early in the outbreak and ‘alert’ clusters of cases. These are clusters (ARDS) OR autopsy findings consistent further transmission within these cities of apparent hospital-acquired cases in staff, with the pathology of pneumonia or RDS resulted in local outbreaks, affecting patients, and visitors to the same health- without an identifiable cause. many hundreds of people. care facility, and that meet the new WHO AND The overall case fatality rate was post outbreak clinical case definition for d) No alternative diagnosis can fully approximately 10% and was highest SARS. explain the illness. (>50%) in those over 60 years of age. A Definition of a SARS alert characteristic feature of the SARS If ‘alert’ clusters are detected from one a) Two or more health care workers in the outbreak was its unprecedented degree institution then those cases should be same health care facility fulfilling the of nosocomial spread, which resulted in urgently isolated and the situation clinical case definition of SARS (see 21% of all cases involving health care immediately discussed with an infectious below) and with onset of illness in the workers. This has resulted in a disease physician AND with the same ten day period. requirement for heath care staff to adopt Communicable Disease Section, DHS. a new standard of infection control and OR This is likely to lead to testing for SARS- personal protection. b) Apparent hospital-acquired illness in coronavirus and the adoption of three or more persons (health care enhanced infection control measures. WHO declared the outbreak interrupted workers and/or other hospital staff on 5 July 2003 at which time there were and/or patients and/or visitors) in the Incubation period more than 8400 cases and same health-care facility fulfilling the The mean incubation period is five days approximately 900 deaths. Mainland clinical case definition of SARS (see with the range of 2–10 days although China reported over 5300 cases and 349 below) and with onset of illness in the there are infrequent isolated reports of deaths. Australia had a single confirmed same 10-day period. longer incubation periods. case of SARS who had visited NSW prior to the global alert and was detected in Clinical case definition of SARS alert Public health significance retrospect by authorities in her home cases (post-outbreak period) and occurrence country. She did not transmit the illness The following clinical case definition has SARS came to the world’s attention in to any of her close contacts. been developed for public health early 2003 when WHO declared a global Five international flights were associated purposes. public health alert in response to a with the transmission of SARS however severe respiratory illness due to an A person with a history of: there has been no evidence of confirmed unidentified communicable pathogen. a) Fever (≥ 38°C) transmission on any flights after WHO AND recommended control measures, which included border exit screening. 202 The blue book: Guidelines for the control of infectious diseases

Reservoir Maximum excretion of the virus from the During the 2003 outbreaks, infants and There has been much interest in respiratory tract seems to occur near day children accounted for only a small determining the source of this new virus, 10 of illness and then declines. The percentage of patients and had much with particular focus on the animal efficiency of transmission appears to be milder disease with better outcomes. species involved and animal husbandry greatest following exposure to severely ill There have been two reported cases of methods seen in Southern China. Early patients or those experiencing rapid transmission from children to adults and investigations have pointed in the clinical deterioration, both of which no reports of transmission from children direction of certain animal species (palm usually occur during the second week of to other children. Three separate civet, racoon dog) however these are not illness. epidemiological investigations have conclusive and more work in this area On reviewing cases of SARS it was found found no evidence of SARS transmission needs to be completed. that when symptomatic cases were in schools. Furthermore, no evidence of isolated within 5 days following onset of SARS has been found in infants of Mode of transmission illness, few cases of secondary mothers who were infected during During the SARS outbreak, the transmission occurred. pregnancy. Further investigation is predominant mode of transmission of the required to determine whether children SARS CoV appeared to be by direct Period of communicability may have asymptomatic or mild mucus membrane contact with SARS-CoV is not thought to be infections. respiratory droplets from either infected transmissible during the asymptomatic persons or fomites. incubation period and there has been no Control measures Preventive measures The evidence to date suggests that evidence that the virus has been spread There are no vaccines available for SARS- spread is predominantly through direct ten days after fever has resolved. CoV. contact or exposure to larger virus-laden droplets that are thought to travel only Susceptibility and resistance As a result of the global outbreak of one to two metres, than by lighter The elderly are more prone to severe SARS there has been resurgence in airborne particles. It has been postulated disease and pose a particular challenge interest and prominence of respiratory that these lighter and smaller aerosols in the recognition of SARS as they may hygiene and cough etiquette as an may have been generated by procedures present with an afebrile illness or with a attempt to reduce transmission of all such as nebulisers or intubations, concurrent bacterial sepsis or forms of respiratory pathogens, including resulting in episodes where significant pneumonia. SARS-CoV. amplification of transmission was In the setting of a SARS outbreak the This includes encouraging all persons observed. diagnosis should be considered for with signs and symptoms of a respiratory Infective stool may also pose a almost any change in health status, even infection to: in the absence of typical clinical features transmission risk but the risks associated • cover the nose and mouth when of SARS-CoV disease, when such with this are not yet clear. coughing or sneezing patients have epidemiologic risk factors New cases occurred primarily in persons for SARS-CoV disease (e.g. close contact • use tissues to contain respiratory with close contact to those very ill with with someone suspected to have SARS- secretions SARS, which was seen in health care and CoV disease or exposure to a location • dispose of tissues in the nearest waste household settings. Less frequently, [domestic or international] with receptacle after use transmission occurred to casual and documented or suspected recent • wash hands after contact with social contacts after intense exposure to transmission of SARS-CoV). a case of SARS (in workplaces, airplanes respiratory secretions and or taxis). contaminated objects and materials. The blue book: Guidelines for the control of infectious diseases 203

Health care facilities should ensure the • use of airborne precautions that • if seen in the practice the clinician availability of materials for adhering to include the use of a P2 (N95 should close the door, open a window, respiratory hygiene/cough etiquette in equivalent) mask (respirator) for all turn off the air-conditioning, put on a waiting areas for patients and visitors: persons entering the room and where mask (N2 if possible), gown, gloves and • provide tissues and no-touch available, a negative pressure eye protection receptacles for used tissue disposal respiratory isolation room (with en- • wash hands after consultation suite) • provide conveniently located • do not self contaminate by touching dispensers for alcohol-based hand rub • restriction of patient movement (and ones own mucus membranes with fitting of a surgical mask if they must contaminated hands • provide soap and disposable leave their room) towels/hand driers for hand washing • make an assessment and call the where sinks are available. • avoiding the use of nebulisers, chest Communicable Diseases Section, physiotherapy, bronchoscopy, During periods of increased respiratory DHS, for an update of the SARS gastroscopy or any intervention that situation and to develop a suitable infection in the community, it may be may disrupt the respiratory tract possible for healthcare facilities to offer management strategy surgical masks to persons who are • placing surgical masks over nasal • where possible any cases of concern coughing and encourage coughing oxygen prongs. should be seen at home with the persons to sit at least three feet away It will become increasingly important for appropriate PPE. from others in waiting areas. clinicians to elicit epidemiological For further details see the Australian Healthcare workers should practice information from their patients as part of interim control guidelines, droplet precautions, in addition to normal history taking. Travel history, http://www.health.gov.au standard precautions, when examining a recent attendance to hospitals or exposure to others who are ill, may assist Control of case patient with symptoms of a respiratory Suspected cases will be managed on infection. in the refinement of a patient’s differential diagnosis and associated risk. their clinical merits with home care =Once there exists an index of suspicion regarded as a suitable option if the of SARS then the appropriate infection The following points may become domestic situation, including its control measures need to be activated appropriate to consider in the primary suitability in terms of infection control, is and suitable PPE worn, (see care setting as a means of managing the judged to be adequate. In such http://www.icg.health.gov.au). These issues of SARS: circumstances, cases will be advised to will dependent on the specific facility • signage at the reception desk may voluntarily restrict their movements. involved and the resources available at advise potential cases to report their Probable and confirmed cases will the time. They include: concerns to the practice as early as require hospitalisation and isolation in a • use of standard precautions (ie hand possible suitable health facility, which will be hygiene) and contact and droplet • any case that could be reasonably determined by the Communicable precautions (ie use of long-sleeved regarded as possibly SARS should be Diseases Section DHS in consultation gowns, gloves and protective eyewear discretely offered a mask and diverted with the treating clinician. The receiving for contact with patient or out of the waiting room and into a hospital will activate its SARS protocol to environment) single room (e.g. returned travellers suitably manage such a patient. from affected region with SARS like symptoms) 204 The blue book: Guidelines for the control of infectious diseases

All suspected, probable and confirmed Contact tracing will be undertaken for Close contacts of cases or returned cases will be excluded from school and those close contacts of probable cases of travellers from regions of SARS outbreak work until clearance is obtained from SARS who were exposed after the patient as defined by DoHA will be allowed to DHS. became symptomatic (see details in the attend school on the provision that they There are no specific treatment Recommendations for tracing & managing remain completely asymptomatic. Such recommendations for SARS. The contacts of SARS cases persons should measure their application of intensive supportive http://www.health.gov.au temperatures daily to ensure that fever is therapy and empirical antimicrobial Contact tracing will not be undertaken not present during the ten days therapy, to cover other infective agents, is for suspected cases of SARS while SARS incubation period. has not been locally transmitted in the usual approach. Antiviral and pulse Cleaning and disinfection steroid therapy have been used in the Australia. Early studies of SARS-CoV show that if past, in different countries with varying The aims of contact tracing is to find, uninterrupted by cleaning or disinfectants it degree of success. provide information to and manage can survive on surfaces in the persons those who may have been Discontinuation of SARS isolation environment, such as on stainless steel exposed to the SARS CoV and who may precautions benches, plastic, wood or cotton, for be incubating or have early signs of the SARS isolation precautions should be between 12 and 72 hours. However, the disease. Management of these contacts discontinued only after consultation with virus is not difficult to kill. It is important to depends on who they were exposed to the local public health authorities and clean surfaces with detergent and water and the circumstances surrounding the the evaluating clinician. and then to disinfect them. Remember that exposure. Control of contacts disinfectants need the appropriate time at Only people who have been close to an Well close contacts will be placed under the appropriate concentration to be unwell person with SARS are at any either passive or active surveillance, effective. whilst all unwell close contacts of significant risk of acquiring infection. For The different methods available for probable cases will be placed under this reason only close contacts are disinfecting include: sought to implement public health active surveillance and isolated in an Heat (56 degrees Celsius) is very contact tracing measures and control appropriate setting. effective, so dishes, linen and other disease spread. A close contact is a It should be remembered that one of the washable items can be disinfected by person who has lived, worked or had most important available measures to washing in hot water and detergent. other dealings with a SARS case that prevent the spread of SARS CoV is the have caused them to be within a meter application of respiratory precautions Alcohol is effective. Tests show that 75% of the case or who has had direct and scrupulous hand washing. Contacts ethanol kills the virus at room contact with respiratory secretions from should be advised of such and also for temperature in less than 5 minutes. a case while not wearing personal the need to seek immediate medical Slightly lower concentrations of alcohol protective equipment. attention if they develop the initial would take a slightly longer time. Alcohol symptoms of SARS. Daily temperature can be found in alcohol rubs (for hands), monitoring for ten days after a break in alcohol impregnated wipes and swabs exposure from the SARS case is such as used to disinfect skin, and advisable. methylated spirits. The blue book: Guidelines for the control of infectious diseases 205

Acetone is effective. 10% acetone will kill • Centres for Disease Control and the virus in less than 5 minutes. Prevention 2004, In the absence of Phenol (2%) is effective and may be SARS-CoV transmission worldwide: found in some hospital grade guidance for surveillance, clinical and disinfectants. laboratory evaluation, and reporting, Version 2, http://www.cdc.gov/ Bleach has not yet been tested against ncidod the SARS coronavirus. However bleach is an effective disinfectant for many other • Communicable Diseases Network viruses and is likely to be effective. Australia 2003, Recommendations for Surfaces to be disinfected with bleach tracing and managing contacts of SARS must first be cleaned with detergent and cases, Australian Government water. An appropriate dilution of 1 in 100 Department of Health and Ageing, of most household bleach provides http://www.health.gov.au sodium hypochlorite at 500 ppm. • World Health Organization http://www.who.int/csr Additional sources of information • World Health Organization 2003, Alert, • Australian Government Department of verification and public health Health and Ageing, management of SARS in the post- http://www.health.gov.au outbreak period, http://www.who.int/ • Australian Government Department of csr Health and Ageing 2004, Severe acute • World Health Organization 2003, respiratory syndrome (SARS) case Consensus document on the definitions, epidemiology of severe acute http://www.health.gov.au respiratory syndrome (SARS), • Centres for Disease Control and http://www.who.int/csr Prevention, Atlanta USA see http://www.cdc.gov/ncidod/sars/ • Centres for Disease Control and Prevention 2004, Clinical guidance on the identification and evaluation of possible SARS-CoV disease among persons presenting with community- acquired illness Version 2, http://www.cdc.gov/ncidod 206 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 207

Shigellosis

Victorian statutory requirement associated with serious disease and a Period of communicability Shigellosis (Group B disease) must be high case fatality rate. Shigella is communicable during the notified in writing within five days of Asymptomatic infections occur and acute phase and while the infectious diagnosis. carriage may persist for months. agent is present in faeces which is usually no longer than four weeks. School exclusion: exclude until after Method of diagnosis Asymptomatic carriage and excretion diarrhoea has ceased. Diagnosis is made by isolation of Shigella may persist for months. spp. from a clinical specimen. Infectious agent Susceptibility and resistance The genus Shigella consists of four Incubation period Everyone is susceptible to infection, with species: The incubation period depends on the infection following ingestion of a small serotype. It varies from twelve hours to • Group A: Sh. dysenteriae number of organisms. In endemic areas seven days but is usually one to three • Group B: Sh. flexneri the disease is usually more severe in days. • Group C: Sh. boydii young children. The risk of infection is increased in men who have sex with • Group D: Sh. sonnei Public health significance and occurrence men, those with immune deficiency Groups A, B and C are further divided Shigella infection occurs worldwide disorders, by attendance at child care or into approximately 40 serotypes, however the incidence of specific contact with a child in child care, and in designated by numbers. serotypes varies by country. Sh. sonnei is international travellers who do not take the most common type reported in adequate food and water safety Identification precautions. Clinical features Victoria and Australia. Sh. dysenteriae and Sh. flexneri are usually acquired Shigellosis is characterised by an acute Control measures overseas and are often resistant to onset of diarrhoea, fever, nausea, Preventive measures multiple antibiotics. In Victoria outbreaks vomiting and abdominal cramps. Good personal hygiene is the single most have occurred in child care centres and Typically the stools contain blood, mucus important preventive measure. Frequent amongst men who have sex with men. and pus, although some persons will and thorough hand washing is important present with watery diarrhoea. Two-thirds of the cases and most of the before eating and food handling and after Complications include toxic megacolon deaths worldwide are in children less toilet use, especially in young children and reactive arthritis. Rarely haemolytic than ten years. The disease is rare in who may not be completely toilet trained. uraemic syndrome can occur. The infants under six months of age, Educate travellers on the need for safe infectious dose required to produce particularly those who are breastfed. food and water consumption. disease is low and may be as few as ten Secondary attack rates in households Control of case organisms. may be as high as 40%. Treatment is usually supportive for mild Illness is usually self-limited and lasts illnesses. Antibiotics may shorten the from several days to weeks with an Reservoir duration and severity of illness however average of four to seven days. The Humans. their use should be based on the severity of infection depends on host Mode of transmission serotype, severity of illness and host factors such as age and nutritional status Faecal-oral transmission is the most characteristics, for example if they are a and the serotype. Infections with Sh. important mode of transmission of child in child care, food handler or suffer sonnei usually result in a short clinical Shigella however infection may be spread chronic illness. Multi-drug resistance is course and low case fatality rate. In via contaminated food, water, milk or by common, particularly for overseas- contrast, Sh. dysenteriae is often flies. acquired strains. The choice of antibiotic 208 The blue book: Guidelines for the control of infectious diseases

should be based on the antibiogram of Control of environment the serotype. Anti-motility drugs are Remove contaminated food and/or thought to increase the risk of prolonged water sources. Strict attention should be carriage. paid to environmental hygiene in child Cases should be educated on the care centres, institutions and food importance of personal hygiene, premises. particularly after using the toilet and Outbreak measures before and after food handling. Two or more related cases should be Food handlers should be excluded from considered indicative of an outbreak and work until two negative stools have been require investigation. These cases should obtained, or until at least 48 hours after be reported immediately to the the diarrhoea has ceased and rigid Department of Human Services. Attempt personal hygiene measures can be to determine a common source of assured. infection and identify those at risk of Cases in institutions should be separated infection. from non-infected residents if possible. Refer to the Guidelines for the Control of contacts investigation of gastrointestinal illness for The diagnosis should be considered in further advice and management of symptomatic contacts however stool outbreaks. cultures may be confined to food handlers and those in situations where the spread of infection is particularly likely (child care centres, hospitals, institutions). Symptomatic contacts of shigellosis patients should be excluded from food handling and the care of children or patients until investigated. The blue book: Guidelines for the control of infectious diseases 209

Smallpox (variola)

Victorian statutory requirement prodromal phase. This occurs rarely as a A patient is no longer infectious once all Smallpox (Group A disease) must be petechial rash. This may be the scabs have separated from the skin notified immediately by telephone or fax misdiagnosed as meningococcal disease, which is usually three to four weeks after followed by written notification within five erythema multiforme or measles. the onset of the rash. Recovery results in days. By the second or third day fever begins the complete clearing of the virus from the body and prolonged immunity. Smallpox is included on the to descend from its peak (40.5 to Commonwealth Quarantine List and all 38.5 C) and the eruptive phase begins The major differential diagnosis is cases will need to be notified immediately with the development of rash lesions. chickenpox and disseminated herpes to the State Chief Quarantine Officer. These lesions first appear on the buccal simplex infections. and pharyngeal mucosa and then Smallpox is subject to Australian Smallpox may be complicated by emerge on the face, forearms and hands. quarantine. secondary bacterial skin infection, The rash spreads down, and within a day corneal scaring, , arthritis, Infectious agent the trunk and lower limbs are involved. osteomyelitis, bronchitis, pneumonitis, Variola virus is a DNA virus of the genus Smallpox produces a single crop of pulmonary oedema and encephalitis. Orthopoxvirus. lesions which are distributed in a Method of diagnosis The virus used in the live smallpox centrifugal pattern: most profuse on the The diagnosis of smallpox will be made vaccine is known as the vaccinia virus face, more abundant on the forearms on the basis of a consistent clinical and is also a member of the genus and lower legs than the upper arms and presentation combined with the results Orthopoxvirus. thighs, and often involve palms and of electron microscopy and PCR testing soles. which will be performed at the National Identification Prominent surfaces and areas most High Security Quarantine Laboratory at Clinical features exposed to irritation are more heavily Victorian Infectious Diseases Reference Smallpox is a severe prostrating illness involved by the rash. Protected surfaces Laboratory in Melbourne. characterised by fever and a macular, such as flexures and depressions (axilla) papular, vesicular and pustular rash with are usually spared. Incubation period an observed mortality rate of 30%. There The incubation period is regarded to be The eruptive lesions appear as flat are three major forms. The most seven to 17 days, with a median of 12 discoloured macules that progress to common form described below occurs in days. 90% of cases. The remaining two are firm papules on the second day of the known as haemorrhagic and malignant rash. These are typically described as Public health significance (flat) variants. These both have ‘shotty’. They become clearly identifiable and occurrence significantly higher mortality (greater than as vesicles on the fourth or fifth day of In 1980 the World Health Organization 95%) and seem to be related to the rash and progress to pustules on day (WHO) declared smallpox the first alterations in immune status. seven. communicable disease ever to be globally eradicated. This was a direct Common smallpox begins with Day ten commonly sees the pustules at consequence of the Global Smallpox symptoms of fever (100%), headache maximal size and the lesions then Eradication Program which was achieved (90%), backache (90%), chills (60%), commence to flatten. Approximately 14 by a population based smallpox vomiting (50%), malaise, prostration and days after rash onset the pustules begin vaccination strategy. cough. Less commonly pharyngitis and to dry up and crust. Most pustules begin severe abdominal pain are observed. In to scab and separate at day 19. Lesions The virus has been retained legally under pale-skinned patients an erythematous on the palms and soles separate last and strict security in two World Health rash sometimes accompanies the typically leave pitted scars. Organization collaborating centres in the USA and the Russian Federation. 210 The blue book: Guidelines for the control of infectious diseases

The virus is believed to have been part of and air-conditioning systems. Such Susceptibility and resistance the bio-weapons research of certain spread is most likely in instances where Resolved infection confers lifetime countries and there have been recent the case has a significant cough. immunity. concerns that non-state actors may Cases may contaminate objects in their Pregnant women and those who are obtain access to the virus for deliberate environment including their clothing and immunocompromised are more release. linen with the large droplets or aerosols susceptible to variant forms of smallpox. A single confirmed case of smallpox during sneezing or coughing and these It is unclear how long the smallpox would prompt a global public health alert fomites may serve as a further route of vaccine will provide effective immunity from the World Health Organization and transmission. but it is unlikely to be more than 10 would raise the spectre of an intentional Physical contact with a smallpox pustule years. As a result essentially all persons release. or crusted scab may also transmit the in Victoria and Australia will be regarded Historically variola major has a significant virus. The virus has been found to survive as susceptible to smallpox. mortality and it would be reasonable to in scabs for many years, however expect a greater impact upon today’s encased in this form it is not considered Control measures unimmunised and older populations. It is to represent a significant infectious risk. Preventive measures The Australian Government Department clear that an outbreak would be of Body fluids are also infectious and care is of Health and Ageing has stockpiled a extreme public concern requiring action needed for the disposal of clinical waste. at the highest level of government and certain amount of smallpox vaccine involving the mobilisation of significant The variola virus is thought to be unlikely which will be accessed under appropriate resources. to survive on its own for more than 48 situations. hours when exposed to normal In the event of an outbreak, there will be Reservoir environmental conditions (ambient a stepwise process to vaccinate persons Smallpox is a disease only of humans temperature, usual humidity and sunlight who will be required to assist in its and there are no non-human hosts. exposure). containment such as doctors, nurses and During the smallpox era the disease had Mode of transmission ambulance personnel. secondary household or close contact The variola virus is most frequently All others will be offered vaccination only attack rates of up to 80%. transmitted from an infectious person via if they have had contact with a case or direct deposition of large, infective, Period of communicability form part of a ‘ring vaccination’ control airborne droplets of saliva onto the nasal, Patients are not infectious during the strategy. oral or pharyngeal mucosal membranes asymptomatic incubation period. They Control of case during close, face to face contact with a become increasingly infectious after Any patient that raises a concern of . onset of fever and this usually results smallpox must be notified to the The generation of infectious fine-particle from the release of virus from Communicable Diseases Section of the aerosols provides a possible albeit less oropharyngeal lesions. Department of Human Services as soon common means of smallpox For the purpose of contact tracing, cases as possible such that a mobile smallpox transmission. This may result in the are regarded as infectious 24 hours prior care team can be dispatched to provide infection of persons involved in non-face to the recognition of fever, and any a swift and expert provisional diagnosis, to face contact with the case, with the contacts identified from this time on and to implement suitable patient care virus carried in aerosols spread by drafts need suitable management. and public health management. The blue book: Guidelines for the control of infectious diseases 211

All such patients (and their possessions) Those who meet the possible or • Active surveillance for 17 days after the should be placed in the best available suspected criteria will be placed in the last exposure form of isolation as soon as possible. observation ward of the smallpox care – Daily reporting of the contact by They should have limited contact with centre. phone to the Department of Human any persons other than those directly Control of contacts Services will be required involved in their care, who must wear The strategy of ring vaccination will be personal protective equipment. Any air – Details of oral temperature and used in the control of any smallpox presence of constitutional symptoms conditioning should be turned off outbreak. This means that all contacts of immediately. a case will be immunised (category A – If there is failure to contact, the All persons in contact with the case or and B, see below) and as an extra Department will actively follow up those sharing the same airspace precaution, those persons with ongoing cases by phone or in person. (hospital or practice staff, other patients household contact with category A • Restriction of movement from seven etc) should be requested to remain in a contacts, during the formal monitoring days after first exposure until 17 days safe area until the smallpox care team period, will also be offered access to the after last exposure. arrives and makes an assessment. They vaccine. – Avoid contact with unvaccinated may need to be given access to smallpox Category A, primary contacts persons immunisation in the short term and their These are persons who are likely to be – During this time contact must stay details, including contact numbers, will exposed to the virus through large away from school and work be essential to collect. This should be droplets or contaminated fomites. They – Remain within local area as defined commenced as soon as practicable. The include: smallpox care team will advise about by the Department • Household contacts. All usual infection control matters including • If symptomatic, category A cases need residents and any visitors who had disinfection and provide information to to stay at home and immediately spent more that one hour at the those present. contact the Department. address during the infectious period. Cases will be categorised as possible, – A category A contact who develops • Face to face contacts (within two suspected, probable or confirmed, fever will be regarded as a possible metres) during the infectious period. depending upon the epidemiology, case and transferred immediately to This will include work and social clinical presentation and the results of the observation ward of the smallpox settings as well as unvaccinated health electron microscopy and PCR testing of care centre vesicular fluid. care and emergency services personnel. – A category A contact who develops All confirmed and probable cases will be fever and rash will be regarded as a • contact. All persons with direct managed in the treatment ward of the probable case and transferred contact with clothing or articles that smallpox care centre where they will immediately to the treatment ward of have been used by infectious cases of receive optimal health care by staff who the smallpox care centre. have been successfully immunised, smallpox. • Outside the restricted period category whilst maintaining appropriate isolation Actions required A contacts will need to stay within the precautions for the community. • Urgent vaccination, preferably before local area until their vaccination site is day three but up to day seven. completely healed and their formal monitoring period is over. 212 The blue book: Guidelines for the control of infectious diseases

Category B, primary contacts • Restricted movement: • Passive surveillance and no restriction These contacts are less likely to have – Category B contacts will not be of movement: been exposed to the virus than Category allowed to travel abroad until their – There are no monitoring or A contacts. They include: vaccination site is completely healed restriction requirements necessary • All persons who have shared a room or and their formal surveillance period unless the primary contact becomes other enclosed spaces with the case is over. symptomatic. If they become whilst infective and not meeting the – No other restrictions of activity are confirmed with smallpox, then the criteria of category A contacts required unless the case is unwell. secondary contacts will be – These may include those who have reclassified as a category A contact • If symptomatic they will be admitted to and will need to be managed visited the same premises or the smallpox care centre: travelled on the same public accordingly. transport (trains, planes or buses) or – Category B contacts who develop Unimmunised primary contacts who have shared the same floors of fever will be classified as possible Definition buildings or the same air cases and transferred to observation These are primary contacts (both conditioning space with an infectious ward of the smallpox care centre. category A and B) who fail to respond to case. – Category B contacts who develop the vaccine after three days, who are Action required for category B contacts fever and vesicular rash will be vaccinated later than three days after classified as probable cases and first exposure to the virus, or who refuse • Vaccinate unless contraindicated transferred to the treatment ward. to be vaccinated. • Commence passive surveillance: Secondary contacts Action – Details will be taken by the These are persons who will have ongoing • Limited options are available for the Department of Human Services and household contact with category A pharmacological management of information provided as to nature of contacts during the formal monitoring persons vaccinated late. The smallpox smallpox and actions to be taken if period. As such they are at risk of response team’s infectious disease symptoms develop (fever, rash or exposure to the virus if the primary specialist may suggest the use of constitutional symptoms). contact becomes symptomatic. vaccinia immune globulin or cidofovir in – If symptoms develop they must Secondary contacts would be expected very limited circumstances. to include usual household residence of immediately contact the Department • Category A primary contacts who are and remain at home, avoiding category A contacts, together with any visitors to the household who expect to categorised as unimmunised, will be contact with all unvaccinated required to remain in isolation persons. spend extended periods of time there, during the formal monitoring period. accommodation until the incubation – Surveillance will continue until 17 period has elapsed. Actions required for secondary days after the last exposure to the • Category B primary contacts will be virus. contacts • Vaccinate unless contraindicated: managed as if they were a category A contact (active surveillance, restricted – If immunisation is contraindicated movement from day seven after first then the secondary contact will need exposure to day 17 after last exposure, to avoid contact with the primary see above). contact until the vaccination site is completely healed. The blue book: Guidelines for the control of infectious diseases 213

Control of environment remain there until disinfected or disposed All persons in contact with a case of of appropriately. This includes all linen, smallpox must wear the appropriate dressings and disposable eating utensils personal protective equipment (PPE) and and medical notes. in order to limit any further spread, this will be removed and the person required Outbreak measures to shower on leaving the infected area. Smallpox management will be framed in This PPE includes gloves, theatre cottons one of the five Australia response codes with head cover, disposable apron, eye detailed below. protection, foot wear such as overshoes, Australian response codes for smallpox and a P2 respiratory mask. • Response code 0: Smallpox remains eradicated – no credible threat of a Until the smallpox care team arrives, the release possibly infected area should be cordoned off and access limited to those • Response code 1: Imminent threat or a case overseas already present and those required for • Response code 2: One case or a cluster of related cases in Australia urgent medial care. The case of concern • Response code 3: Unrelated cases or unrelated clusters occurring in Australia should be isolated as best as possible and all others should remain within a • Response code 4: Outbreak controlled – no further cases occurring safe distance of the cordoned off area. Information and all care should be Emergency plans would be activated in However if a case does present to an ED, afforded all persons involved, with sequence with these codes as outlined then activation of the ED infection particular attention being made to advise in the Australian Government’s control procedures should be instituted, that the earliest possible access to the Guidelines for the smallpox outbreak, such that appropriate action is taken to vaccine will provide the best possible preparedness, response and limit any spread into the broader outcome if the case in fact proves to be management. This would include alerts to hospital. smallpox. the community and health providers, roll out of the smallpox vaccination strategy, International measures The smallpox care team will advise on mobilisation and augmentation of the If there are smallpox cases overseas suitable decontamination processes and smallpox care teams, and commissioning then the Australian Government may the disposal of possibly infectious of the smallpox care centre. divert all aircraft from that country, to a materials. This will be in accordance with limited number of airports where the Guidelines for the smallpox outbreak, Special settings screening, immunisation and the preparedness, response and General hospital wards and their appropriate isolation and quarantine management. emergency department (ED) may be at measures will be applied as required. increased risk of attending to smallpox As the virus is transmitted through cases. In order to limit this, all Additional sources of information infectious respiratory droplets and bodily community concerns regarding smallpox • Australian Government Department of fluids or contaminated clothing, need to be notified to the Department of Health and Ageing 2004, Guidelines for dressings, linen, towels or clinical waste, Human Services immediately. The smallpox outbreak, preparedness, every effort must be made by relevant Department will dispatch a smallpox care response and management. staff to limit spread through these routes. team to make an urgent assessment. In Air conditioning must be isolated or • Fenner, F 1988, Smallpox and its this way, cases will be diverted to turned off and the time documented. Any eradication, World Health Organization. smallpox care centres without disrupting object that enters the infected area must the working of any hospitals. 214 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 215

Staphylococcal infections

Victorian statutory requirement • food poisoning by releasing toxins into Reservoir Notification is not required. food Human carriers are a major source of School exclusion: for impetigo due to • by releasing infection. Staphylococci have prolonged exclude until toxins into the blood stream. survival in the hospital environment due to resistance to antiseptics and appropriate treatment has commenced. Method of diagnosis disinfectants. Diagnosis is confirmed by isolation of the Infectious agent organism from relevant specimens. Their There are nineteen species of Mode of transmission antibiotic resistance profile is important staphylococci. The most significant Staphylococci are most often transmitted in management. human pathogens are Staphylococcus by direct or indirect contact with a person who has a discharging would, a aureus and Staphylococcus epidermidis. Incubation period clinical infection of the respiratory or Methicillin resistant The incubation period is variable and urinary tract, or one who is colonised S. aureus (MRSA) and vancomycin- indefinite. It is most commonly four to with the organism. MRSA can be carried resistant S. aureus (h-VISA, VISA and ten days. VRSA) are significant pathogens in on the hands of healthcare personnel hospital-acquired disease. Virulence Public health significance and is a likely mode of transmission varies greatly amongst the bacterial and occurrence between patients and staff. strains. Staphylococcal infections are frequent Contaminated surfaces and medical but are usually contained by immune equipment are also possible sources of Identification mechanisms to the site of entry. MRSA. Clinical features Approximately 20–30% of the population Period of communicability Staphylococcal infection presents with a are colonised with S. aureus in the Communicability exists as long as variety of different clinical and anterior nasal passages. The highest purulent lesions continue to drain, or the epidemiological patterns amongst the incidence of disease usually occurs in carrier state persists. general community, newborns, people with poor personal hygiene, hospitalised patients and menstruating overcrowding and in children. However Susceptibility and resistance women. It may cause: anyone can develop a serious People who are most susceptible to • purulent skin infections such as a staphylococcal infection including fit infection are the chronically ill and , abscesses, styes, impetigo and young people. newborns. scalded skin syndrome Since the late 1970s MRSA strains have Mechanisms of immunity are not well • systemic infections such as been identified in Victoria as a major understood. An experimental vaccine pneumonia, osteomyelitis or cause of nosocomial infections and with a short duration of immunity has endocarditis outbreaks. MRSA accounts for been developed to assist patients with approximately 30–50% of hospital- • urinary tract infections due to end-stage renal disease. acquired S. aureus isolated from S. saprophyticus in young women or Resistance to penicillin-related normally sterile sites. Vancomycin S. epidermidis with indwelling catheters antibiotics in the hospital setting is resistant strains have been reported. common and includes MRSA. Two • hospital-acquired (nosocomial) Health care employees and other carers specific types of vancomycin infection of surgical wounds or may develop intermittent colonisation antimicrobial resistant S. aureus called treatment lines with MRSA. These workers rarely develop VISA and VRSA have recently emerged. infection. 216 The blue book: Guidelines for the control of infectious diseases

Control measures Outbreak measures Preventive measures The Department of Human Services may General measures: investigate unusual clusters of • maintain good hygiene through public staphylococcal infection in the education in relation to hand washing, community, particularly those associated food preparation and avoiding sharing with antibiotic resistant strains. toilet articles This may include: • cover purulent lesions with a • investigation of the source of infection waterproof dressing. including microbiological screening of In the health care setting: contacts • educate hospital staff regarding the • advising on added infection control importance of hand washing precautions for cases and carriers • use common narrow spectrum • treatment recommendations for cases antibiotics where possible. and carriers. Control of case Special settings Advise isolation until treatment of the Hospital nursery workers with minor infection has commenced. Search for lesions such as boils or abscesses and cover draining lesions. Infected should not have direct contact with persons should avoid contact with infants until the lesion has healed. infants and chronically ill patients. Added All known or suspected cases in a infection control precautions may be nursery should be isolated. recommended for cases with infections In school settings, the child should be due to multi-resistant organisms. excluded from school until specific Control of contacts treatment begins. Lesions must be Routine contact tracing is not usually covered with a watertight dressing. required. Contacts do not need to be excluded. Determining the carrier status amongst family members of a pathogenic strain may be occasionally useful, in which carriers might be recommended antibiotics to eliminate the bacteria such as mupirocin. Control of environment Encourage hand washing, especially in the hospital setting. The blue book: Guidelines for the control of infectious diseases 217

Streptococcal disease (Group A beta-haemolytic streptococcus)

Victorian statutory requirement Antigen detection tests are available for Mode of transmission Notification is not required. rapid identification. A rise in serum GAS is usually transmitted via large antibody titres (anti-streptolysin O, anti- School exclusion: exclude until the child respiratory droplets or direct contact with hyaluronidase, anti-DNAase B) may also has received antibiotic treatment for at infected persons or carriers. It is rarely be demonstrated in sera taken in the least 24 hours and the child feels well. transmitted by indirect contact through acute and convalescent phases of the objects. Outbreaks of streptococcal Infectious agent disease. infection may occur as a result of Streptococcus pyogenes or Group A ingestion of contaminated foods such as Incubation period streptococci (GAS) has approximately 80 milk, milk products and eggs. The incubation period is usually one to serologically distinct types. Those three days. producing skin infections are usually of Period of communicability With appropriate antibiotic therapy GAS different serological types to those that Public health significance cause throat infections. is communicable for 24–48 hours. In and occurrence untreated uncomplicated cases Identification The incidence of GAS infections and their communicability can last for 10–21 days. sequelae are not well documented in Clinical features Communicability can be prolonged in Australia except in Aboriginal The spectrum of disease caused by GAS untreated complicated cases. communities in northern Australia. In the includes: USA, acute pharyngitis is one of the Susceptibility and resistance • superficial infections such as most common reasons for seeking Pharyngitis and tonsillitis are common in pharyngitis, impetigo and medical advice and GAS is thought to be children aged 5–15 years, whereas • scarlet and puerperal fever responsible for 15–30% of pharyngitis in pyoderma occurs more frequently in • severe invasive disease such as children and 5–10% in adults. The children aged less than five years. Most necrotising fasciitis, toxic shock community burden of pyoderma in people in their lifetime will develop a GAS syndrome and septicaemia industrialised countries in not well throat or skin infection and many of the documented. throat infections may be subclinical. • post-streptococcal immunological People with chronic illnesses like cancer sequelae include acute rheumatic fever Preliminary data from a voluntary and diabetes, those on kidney dialysis, or and acute glomerulonephritis. surveillance system implemented in Victoria in 2002 suggests the incidence those who use medications such as Method of diagnosis of invasive GAS disease may be greater steroids, have a higher risk than healthy Superficial infection is diagnosed by than 4 per 100 000 per year, with a case- persons. There is an increased risk of isolation of the organism from infected fatality rate of approximately 11%. infection in varicella (chickenpox). tissues. Invasive infection can be confirmed by isolation of the organism Outbreaks occur in childcare settings, Control measures from a normally sterile site such as institutions, and in remote communities Preventive measures blood. Throat swabs are of limited value in northern and central Australia. There are currently no vaccines available but candidate vaccines are being used in due to the frequency of inapparent Reservoir Streptococcal carriage. Definitive clinical trials. Food-borne disease can be Humans. identification depends on specific prevented by pasteurising milk and milk serogrouping procedures. products and careful preparation and storage of high risk foods, particularly eggs. 218 The blue book: Guidelines for the control of infectious diseases

Control of case Outbreak measures Treatment is dependent on the clinical Outbreak management is dependent on presentation and severity of disease. the setting and specific disease. Seek Evidence has accumulated that advice from the Department of Human antibiotics may not always be indicated Services. in pharyngitis or tonsillitis. The current version of Therapeutic guidelines: Additional sources of information antibiotics (Therapeutic Guidelines • Passmore, J, Kelpie, L & Carapetis, J Limited) should be consulted prior to 2003, ‘Surveillance for invasive group A treatment. streptococcal disease in Victoria-the first 12 months’, Vic Infect Dis Bulletin, Infected children should be excluded vol. 6, no. 2, p. 30, from schools and children’s services www.health.vic.gov.au/ideas centres until they have received antibiotics for at least 24 hours and the child feels well. People with skin lesions should be excluded from food handling until infection has resolved. Control of contacts Consider the diagnosis in symptomatic contacts. Few people who come in contact with GAS will develop invasive GAS disease. At present, the role of antibiotic prophylaxis for close contacts of cases of invasive GAS infection is uncertain. However in certain circumstances, antibiotic therapy may be appropriate for those at higher risk of infection. Control of environment Standard infection control procedures should be applied. The blue book: Guidelines for the control of infectious diseases 219

Syphilis

Victorian statutory requirement • late latent syphilis where latent syphilis • Treponemal tests measure specific Syphilis (Group C disease) must be has existed for two or more years or of treponemal antibodies in serum. These notified in writing within five days of indeterminate duration, in the absence include Treponema pallidum particle diagnosis. of neurosyphilis and other symptoms agglutination, enzyme immunoassay and signs of disease and fluorescent Treponemal antibody Specific information must be notified absorption tests. Once these tests are under the Health (Infectious Diseases) • tertiary syphilis where cardiovascular reactive they usually remain so for life Regulations 2001. To maintain involvement and neurosyphilis is and give no indication of current confidentiality, only the name code (first present. disease activity. Enzyme two letters of the surname followed by Syphilis in pregnancy immunoassays with highly purified the first two letters of first name) is Foetal infection may result in abortion, Treponema pallidum antigens are required. A questionnaire is sent to the stillbirth, premature delivery and becoming more commonly used for diagnosing doctor to collect additional perinatal death. In congenital syphilis, screening for syphilis. These assays information on the case that is essential generalised systemic disease in a live have a high specificity and sensitivity. for detecting disease trends and born infant is present. IgM enzyme immunoassay for the informing policy development. Method of diagnosis detection of IgM antibodies to Medical practitioners have a statutory Syphilis can be diagnosed by the Treponema pallidum is a useful assay obligation under the Children and Young demonstration of spirochaetes in the for the diagnosis of congenital syphilis. Person’s Act 1989 to notify the exudate from primary or from • Non-treponemal tests such as rapid Department of Human Services’ Child the mucous membrane lesions of plasma reagin (RPR) and venereal Protection service if they believe that a secondary syphilis, using dark field diseases research laboratory test child is in need of protection on the basis microscopy or immunofluorescence. measure antibodies that are produced of sexual abuse. Dark field microscopy is a difficult in response to syphilis and also to a Infectious agent technique and requires an experienced relatively large number of other The spirochaete Treponema pallidum, operator for reliable results. The test is conditions. This results in biological subspecies pallidum is the infective unreliable on mucous membrane lesions false positives. The non-treponemal agent. due to the presence of morphologically test gives an indication of current similar saprophytic spirochaetes. Dark disease activity. Identification field is also best done on site, as drying All sera showing reactive serology on Clinical features of the exudate during transport to the screening tests should be forwarded to a Syphilis is characterised by a primary laboratory renders the specimen reference laboratory for confirmatory lesion, a secondary eruption involving unsuitable for microscopy. testing. skin and mucous membranes, long Immunofluorescence is more sensitive periods of latency, and late lesions of and does not have to be performed It is necessary to interpret syphilis skin, bone, viscera, cardiovascular and immediately. It is suitable for use with serology in the context of: central nervous systems. mucous membrane lesions but it is not • clinical history and examination The stages of syphilis can be divided currently performed by the Victorian • serial RPR titres tested in parallel into: Infectious Diseases Reference where possible (results obtained from Laboratory. • early syphilis where primary (), different laboratories are not directly secondary (rash or condylomata lata) More commonly syphilis is diagnosed comparable) or latent syphilis (asymptomatic) of less using a combination of treponemal and • treponemal test results than two years duration exist based on non-treponemal serological tests: • a past record of treatment. serology results 220 The blue book: Guidelines for the control of infectious diseases

It is essential that all cases of syphilis outbreaks. Imported infectious cases Control of case receive close clinical and laboratory could result in syphilis re-emerging as a Penicillin is the drug of choice to treat follow-up. significant public health issue. syphilis.

Lumbar puncture is advised when there Reservoir Further information on the clinical are: management of patients with syphilis can Humans are the only reservoir. • neurological or ophthalmic signs or be found in the latest editions of the symptoms Mode of transmission Therapeutic guidelines: antibiotic Transmission occurs primarily by sexual (Therapeutic Guidelines Limited) and the • evidence of active tertiary syphilis contact. Transplacental infection of a National management guidelines for • treatment failure foetus may occur during the pregnancy sexually transmissible infections • HIV infection with late latent syphilis or of an infected woman. Foetal infection (Venereology Society of Victoria, 2002). syphilis of unknown duration. occurs with high frequency in untreated The necessity for long term follow-up early infections of pregnant women and Note that other sexually transmissible with repeat serology and the frequent with lower frequency later in the disease infections may be present in addition to presence of complicating factors makes or in late latency. Syphilis may also be syphilis. Patients in whom syphilis is it desirable to seek specialist advice. transmitted by transfusion of blood from diagnosed should be encouraged to be Control of contacts infected individuals, however this risk is tested for HIV infection. Sexual contacts should be identified. The minimised by the screening of all extent of contact tracing depends on the donated blood in Australia. Incubation period clinical stage of infection. The incubation period is from ten days to Period of communicability three months and is usually three weeks. For primary syphilis, all persons having A case is considered sexually infectious sexual contact with the index case during Public health significance until the end of the early latent period the three months preceding onset should and occurrence which is approximately two years after be evaluated. Such contacts should be This is a complex disease. Sequelae infection. Infectious moist treated as for the case, even if their include neurosyphilis, cardiovascular mucocutaneous lesions are present in serology is negative. syphilis and congenital infection with the primary and secondary stages of For secondary syphilis, this period should foetal death, stillbirth and abortion. syphilis and may reoccur intermittently in be extended to six months and for early Testing and effective treatment are the early latent period. These lesions may latent syphilis, to twelve months. available to facilitate the interruption of not be apparent to the infected For late latent syphilis, any sexual disease transmission. Immune responses individual. partners and also children of infected are only partially protective and Susceptibility and resistance women should be evaluated. reinfection may occur following Everyone is susceptible to infection. treatment. Syphilis enhances the For congenital syphilis, all members of the immediate family should be transmission of HIV, like other diseases Control measures evaluated. that cause genital ulcers. Preventive measures The number of notifications of infectious Education about safe sex practices Contact tracing assistance can be syphilis in Victoria is currently relatively including the use of condoms and early provided by the Department’s partner small. However, syphilis occurs detection of infection by testing of notification officers (phone 9347 1899). worldwide and has a high incidence in people at risk are the main prevention All newborns of mothers with syphilis other parts of Australia. Other developed measures. should be investigated and treated in countries have experienced recent consultation with a specialist. The blue book: Guidelines for the control of infectious diseases 221

Control of environment • Larsen, SA et al 1995, ‘Laboratory Not applicable. diagnosis and interpretation of tests for syphilis’, Clin Micro Revs, vol. 8, no. 1, Outbreak measures pp. 1–21. Not applicable. • Nganampa Health Council 1999, How Additional sources of information to interpret syphilis results – A manual • Australian Government Department of for nursing and medical staff in remote Health and Family Services 1997, area clinics, 2nd ed. Contact tracing manual – a practical • Singh, AE et al 1999, ‘Syphilis: Review handbook for health care providers with emphasis on clinical, managing people with HIV, viral epidemiologic and some biologic hepatitis, other STDs and HIV-related features’, Clin Micro reviews vol. 12, no. tuberculosis, Australian Government 2, pp. 187–209. Department of Health and Family • Venereology Society of Victoria 2002, Services. National management guidelines for • Centers for Disease Control and sexually transmissible infections, Prevention 2002, ‘Sexually transmitted http://www.mshc.org.au diseases treatment guidelines 2002’, Morbidity and Mortality Weekly Report, vol. 51, RR06, pp.1–80. http://www.cdc.gov/mmwr • Egglestone, SI et al 2000, ‘Serological diagnosis of syphilis,’ Communicable Diseases & Public Health, vol. 3, no. 3, pp. 158–62. 222 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 223

Taeniasis

Victorian statutory requirement Subcutaneous cysticerci may be visible tapeworm develops in the intestine over Notification and school exclusion are not or palpable. Calcified cysticerci may be two to three months. The cycle of required. visualised using ultrasound, CT scan or infection repeats when infectious eggs MRI. are passed in the faeces and later Infectious agent ingested by cattle, slowly migrating into Taenia solium (pork tapeworm) causes Incubation period the flesh and transforming into the larval both intestinal infection with the adult Symptoms of cysticercosis may appear stage. tapeworm and somatic infections with from weeks to years after infection. Eggs Infections by T. solium may follow a the larvae (cysticerci). appear in the faeces 8–12 weeks after similar cycle with consumption of infection with the adult T. saginata Taenia saginata (beef tapeworm) causes infected pork leading to the subsequent tapeworm and after 10–14 weeks with T. only intestinal infection with the adult development of adult tapeworms. solium. tapeworm in humans. However human infection may also occur through the consumption of T. solium Identification Public health significance and occurrence eggs. This occurs by direct transfer from Clinical features Taeniasis occurs worldwide. It is the faeces of an infected person or Taenia saginata infections are often commonly seen in parts of Latin through the ingestion of contaminated asymptomatic apart from the anal America, Africa, South East Asia and food or water. When the eggs of passage of tapeworm segments. Eastern Europe. Both forms are usually T. solium are ingested by either humans Infection may be associated with imported to Australia but sporadic locally or pigs the embryos escape the shells epigastric pain, diarrhoea and weight acquired cases of T. saginata infection and penetrate the intestinal wall, with loss. have been reported. subsequent spread of larvae to various Taenia solium adult worm infections are tissues to produce cysticercosis. Many infections are largely also usually asymptomatic. Many tissues asymptomatic, but the larval stage of and organs may be infected by the larval Period of communicability T. solium may cause fatal cysticercosis. form (cysticercosis). Neurocysticercosis T. saginata is not directly transmissible Chronic tapeworm infections contribute is a serious but rarely fatal complication from person to person although to malnutrition for developing which may be manifest as headaches, T. solium may be. Adult tapeworms may communities in many parts of the world. epileptiform seizures and visual or persist in the intestines for up to 30 years and are able to disseminate eggs psychiatric disturbances. Reservoir for all of this time. Eggs may remain Method of diagnosis Humans are the definitive host for both viable in the environment for months. Infection with an adult tapeworm can be species. Cattle are the intermediate host diagnosed through the identification of for T. saginata and pigs for T. solium. Susceptibility and resistance segments, eggs or the head of the Everyone is susceptible to infection. Mode of transmission parasite in faeces or perianal swabs. Infection does not appear to confer Eggs of T. saginata passed in the faeces Microscopic examination of the eggs immunity. cannot differentiate between the two of an infected person are only infectious species. to cattle. Humans are infected by ingestion of raw or undercooked beef Specific serological tests are available to infected with cysticerci bovis, the larval support the clinical diagnosis of stage of T. saginata. In humans the adult taeniasis. 224 The blue book: Guidelines for the control of infectious diseases

Control measures Control of contacts Preventive measures Symptomatic patients exposed to a The public should be advised to avoid suspected source of infection should be faecal contamination of soil, and human evaluated for evidence of taeniasis. and animal food; avoid the use of raw Control of environment sewage for irrigation of pasture soil; and If the history is consistent with local to cook beef and pork thoroughly. infection the source of the infection Beef and pork, should be adequately should be investigated, often with the cooked, for example at 60°C for five assistance of the local government. minutes. Outbreak measures Freezing meat below –5°C for more than Not applicable. four days will kill cysticerci. Meat should be routinely inspected for Additional sources of information evidence of taeniasis at slaughter. • Centers for Disease Control and Prevention, http://www.dpd.cdc.gov Control of case Praziquantel or niclosamide are used for treatment of beef and pork tapeworm infections. Consult the current version of Therapeutic guidelines: antibiotic (Therapeutic Guidelines Limited). Persons harbouring adult T. solium should be immediately identified and treated to prevent human cysticercosis. For cysticercosis surgical intervention may relieve symptoms. For CNS cysticercosis, praziquantel or albendazole may be used, with corticosteroids if indicated. Isolation is not required. The case and relevant caregivers should be advised that the case’s faeces may be infectious and advised on sanitary disposal of wastes. The blue book: Guidelines for the control of infectious diseases 225

Tetanus

Victorian statutory requirement Laryngeal spasm is a very serious Tetanus is still common in developing Tetanus (Group B disease) must be complication which may occur at any countries with low immunisation rates notified in writing within five days of stage and can cause sudden asphyxia. and where contact with animal excreta is diagnosis. Exhaustion and inability to swallow are more common. Tetanus, particularly also associated with severe disease. neonatal tetanus, is a significant cause of School exclusion is not applicable. Case fatality rates vary from 10–90% and death in these settings. Infectious agent are highest in infants and the elderly. Intravenous drug use is an independent Clostridium tetani, the tetanus bacillus is Method of diagnosis risk factor for tetanus in the absence of the causative agent. Clinical features of severe classical acute injuries and may be linked to localised case clusters. Identification tetanus are virtually diagnostic. Clinical features Laboratory confirmation of tetanus Reservoir Tetanus is an acute, potentially fatal infection is often difficult. C. tetani is widely distributed in cultivated disease caused by tetanus bacilli C. tetani antibodies are sometimes soil and in the gut of humans and multiplying at the site of an injury. These detectable in serum samples but may animals. Spores can usually be found produce an exotoxin that reaches the result from waning past immunisation. wherever there is contamination with central nervous system and causes Cultures from the site of infection should soil. muscle stimulation. be attempted although the organism is Mode of transmission Initial features are increased muscle often not recovered. Tetanus is not directly transmitted from rigidity. This may be restricted to and person to person. most pronounced in muscles near the Incubation period injury (localised tetanus). Depending on The incubation period is usually three to Spores may be introduced through severity, muscle rigidity usually affects 21 days although it may range from one contaminated puncture wounds, most parts of the body and is associated day to several months depending upon lacerations, burns or contaminated with hyperreflexia. As a result, features the nature of exposure. Most cases injected ‘street drugs’. Tetanus can result such as neck, back and limb stiffness, occur within14 days. from minor wounds considered too trivial stiff jaw or ‘lock jaw’ (trismus) and a Cases with shorter incubation periods for medical consultation. sardonic smile (risus sardonicus) may tend to have more severe disease and The presence of necrotic tissue or occur. thereby a greater risk of death. foreign bodies encourages the growth of With progression, superimposed painful anaerobic organism such as Public health significance muscle spasms can appear anywhere or C. tetani. Tetanus rarely follows surgical and occurrence involve most body muscles procedures today. Tetanus occurs worldwide but is now simultaneously. Opisthotonos can result. rare in developed countries due to high This is when spasm is most marked in Period of communicability immunisation rates. Infection is most the back muscles causing the head and Spores may remain viable for many years likely in older people who have never heels to bend backward and the body to in the environment. been immunised or who have waning and bow forward. Painful spasms may inadequate immunity. become very frequent and together with background rigidity cause life-threatening interference with respiration. 226 The blue book: Guidelines for the control of infectious diseases

Susceptibility and resistance Control of case Active immunity is produced by Refer the patient immediately to a immunisation with tetanus toxoid and specialised centre with intensive care persists for at least ten years after full facilities. The principles of treatment immunisation. include: Transient passive immunity follows • tetanus immunoglobulin (TIG) by injection of tetanus immune globulin intramuscular injection (TIG) or tetanus antitoxin. • IV penicillin in large doses for 10 to 14 Recovery from tetanus is not necessarily days. Intravenous metronidazole is a associated with immunity. reasonable alternative for patients with immediate penicillin hypersensitivity Control Measures • adequate wound debridement Preventive measures Tetanus toxoid is part of the Australian • careful attention to provide an Standard Vaccination Schedule. Primary adequate airway and to control muscle immunisation for children begins at two spasm months of age and requires three doses • case investigation to determine the of tetanus toxoid-containing vaccine at circumstances of injury two-monthly intervals. Children should • completion of course of active be given a booster at four years of age. A immunisation after recovery. further booster dose is given prior to leaving school (15–17 years of age) and Control of contacts again at 50 years of age. Not required. For further information on tetanus Control of environment vaccination, particularly with respect to Not required. the management of children who have Outbreak measures missed doses, consult the current edition Not applicable. of The Australian immunisation handbook (National Health and Medical Research Council). The use of tetanus toxoid in the management of wounds, with or without tetanus immunoglobulin, is determined by considering the vaccination history of the person and the nature of the wound. For further information on the management of bites and other tetanus- prone wounds, consult the current edition of Therapeutic guidelines: antibiotic (Therapeutic Guidelines Limited). The blue book: Guidelines for the control of infectious diseases 227

Toxoplasmosis

Victorian statutory requirement Serological results require careful Reservoir Notification and school exclusion are not interpretation and should preferably be The main host in Australia is the required. performed and discussed with a domestic cat. Cats acquire the infection reference laboratory. In general, mainly through eating small infected Infectious agent toxoplasma-specific IgG antibody mammals including rodents and birds, Toxoplasma gondii is a protozoal disease. appears two to three weeks after acute and rarely from the ingestion of infected infection, peaks in six to eight weeks and cat faeces. Only young felines harbor the Identification often persists lifelong. parasite in the intestinal tract, where the Clinical features sexual stage of the life-cycle takes place Toxoplasmosis infection is asymptomatic Presence of toxoplasma-specific IgM resulting in the excretion of oocysts in in 80% of people. The most common sign antibody suggests infection within the faeces for 10–20 days. in symptomatic patients is enlarged last two years. False positive IgM results lymph nodes, especially around the neck. are common and should always be Many other intermediate hosts including The illness may mimic glandular fever repeated before final interpretation. They sheep, goats, rodents, cattle, swine, with other symptoms of muscle pain, are common in autoimmune disease. chicken and birds may carry an infective intermittent fever and malaise. Presence of IgA antibodies is said to stage of T. gondii encysted in their tissues. This occurs more commonly in Dormant infection persists for life and correlate with acute infection. muscle and brain. Tissue cysts remain can reactivate in the immunosuppressed Testing paired sera taken two weeks viable for long periods. person. apart is often helpful as is IgG antibody More serious disease can develop or avidity testing. Mode of transmission reactivate in immunosuppressed patients A specific PCR performed on amniotic Adults most commonly acquire with brain, heart or eye involvement, fluid may determine if a foetus has toxoplasmosis by eating raw or pneumonia and occasionally death. become infected. undercooked meat infected with tissue Cerebral toxoplasmosis or chorioretinitis cysts. Consumption of contaminated, Incubation period are frequent complications of AIDS when unpasteurised milk has also been The incubation period is uncertain but the lymphocyte CD4 cell count drops implicated. probably ranges from 5–23 days. below 100 / cu mm. Children may become infected by Acute toxoplasmosis in pregnant women Public health significance ingestion of oocysts in dirt or sandpit can affect the unborn child. In early and occurrence sand after faecal contamination by cats, pregnancy brain damage as well as liver, Toxoplasmosis occurs worldwide in particularly kittens, or other animals. spleen and eye disorders may occur. mammals and birds. Infection in humans The infection may also be transmitted Infection in late pregnancy may result in is common. through blood transfusion and organ persistent eye infection through life. Infections during pregnancy may lead to transplantation. Transplacental Toxoplasmosis acquired after birth severe complications for the foetus. transmission may occur when a woman usually results in no symptoms or only a Primary or reactivated lesions may lead has a primary infection during mild illness. to severe complications in pregnancy. immunosuppressed patients. Method of diagnosis Period of communicability Infection may be diagnosed by Toxoplasmosis is not transmitted from visualisation of the protozoa in biopsy person to person spread except in-utero. material or serology. 228 The blue book: Guidelines for the control of infectious diseases

Oocysts spread by cats sporulate and • cat litter trays should be emptied daily Primary infection in pregnancy can cause become infective one to five days later. and regularly disinfected with boiling serious foetal disease. Infection in the They may remain infective in water or water to dispose of the oocysts before first trimester results in a low foetal moist soil for over a year. they become infective. (15%) but a higher risk of Tissue cysts in meat remain infective for Cats should only be fed with dry, canned serious disease. Infection later in as long as the meat is edible and under- or boiled food and should be discouraged pregnancy results in a higher infection cooked. from hunting and scavenging. However, rate but generally less severe disease. direct contact with cats is rarely the Diagnosis and treatment during Susceptibility and resistance cause of infection. Cats are generally pregnancy appears to reduce the effects Everyone is susceptible to infection. infected as kittens and only excrete the on the baby. About 75% of women of childbearing age oocysts for two weeks after their original False positive IgM antibody test (and less are susceptible. infection. commonly IgG) results do occur and Immunity is thought to be life long Sandpits should be covered when not in treatment should never begin without however patients undergoing use to stop cats defecating in the pit. further testing. Where infection of the immunosuppressive therapy, in particular Control of case mother is confirmed, treatment is for haematological malignancies, or Isolation of patient is not required. indicated. patients with AIDS, are at high risk of Amniocentesis with PCR testing can be developing illness from reactivated Specific anti-protozoal treatment may be carried out to determine whether infection. indicated in immunosuppressed persons, infections during pregnancy, or where transmission to the foetus has occurred. Control measures there is eye or other organ involvement. Newborns Preventive measures Specialist advice should be sought. Newborns of mothers with primary No immunisation is available. Immunosuppressed persons may also infection during pregnancy or active Pregnant women and require prophylactic treatment for the infection, and immunosuppressed immunosuppressed people should be duration of their immunosuppression. patients are treated empirically until advised to: Infants who acquire an infection before congenital disease is ruled out. Where infection is confirmed, treatment is • cook meat thoroughly (until no longer birth may require prolonged treatment to continued for 12 months to help reduce pink) and avoid uncooked cured meat reduce the risk of ongoing active long term effects. products infection. • not consume unpasteurised milk or its Control of contacts Outbreak measures products Not applicable. Not applicable. Special settings • wash all raw fruit and vegetables Additional sources of information Pregnancy carefully before eating • Gilbert, G 2002, ‘Infections in pregnant Children of mothers with evidence of • wash hands thoroughly before meals women’ MJA, vol. 176, pp. 229–236. previous immunity more than six months and after handling raw meat prior to conception are not at risk. • delegate the cleaning of cat litter trays Primary infection in pregnancy is rare to others wherever possible and if this although up to one third of these is not possible, gloves should be worn infections result in transplacental spread during cleaning and hands washed well to the developing foetus. afterward The blue book: Guidelines for the control of infectious diseases 229

Typhoid and paratyphoid fever

Victorian statutory requirement Phage typing is used for characterising S. travellers. The disease commonly occurs Salmonella (Group A disease) must be typhi and S. paratyphi isolates for in association with poor standards of notified immediately by telephone or fax epidemiological purposes and in hygiene in food preparation and handling. followed by written notification within five outbreak settings. A number of phage days. types are recognised. Period of communicability It is communicable as long as typhoid or School exclusion: exclude until approved Incubation period paratyphoid bacilli are present in excreta. to return by the Department of Human The incubation differs for typhoid and Some patients become permanent Services. paratyphoid fever: carriers. Work exclusion: exclusions apply to food- • typhoid fever is usually 8–14 days but Susceptibility and resistance handlers and some health care workers this depends on the infective dose and Everyone is susceptible to infection. (see below). can vary from three days to one month Immunity following clinical disease or Infectious agent • paratyphoid fever is usually one to ten immunisation is insufficient to protect Salmonella typhi, the typhoid bacillus and days. against a large infectious dose of Salmonella paratyphi, with three organisms. recognised serovars A, B and C are the Public health significance infectious agents. and occurrence Control measures Typhoid and paratyphoid infections occur Preventive measures Identification worldwide. Outbreaks occur in areas with Vaccination is not routinely Clinical features poor sanitation and inadequate sewerage recommended, except for travellers who Typhoid fever (enteric fever) is a systems. Approximately 30–35 cases of will be exposed to potentially septicaemic illness characterised initially enteric fever occur in Victoria each year. contaminated food and water in by fever, bradycardia, splenomegaly, The majority of these are returned countries such as in Asia, the Middle abdominal symptoms and ‘rose spots’ travellers, especially from the Indian East, Africa, Latin America and the which are clusters of pink macules on subcontinent. Pacific Islands. the skin. Reservoir Vaccination should be considered for Complications such as intestinal Reservoirs for typhoid and paratyphoid laboratory workers in potential contact haemorrhage or perforation can develop fever are: with Salmonella typhi. in untreated patients or when treatment Three typhoid vaccines are currently is delayed. • typhoid fever: Human gallbladder carriers and rarely human urinary available in Australia. The live oral Paratyphoid fever presents a similar carriers vaccine and Vi capsular polysaccharide clinical picture but is usually milder, injectable vaccine generally cause few shorter in duration and with fewer • paratyphoid fever: Humans and rarely adverse reactions. domestic animals. complications. A combination hepatitis A and typhoid Method of diagnosis Mode of transmission injectable vaccine is also available. All Diagnosis is made by culture of typhoid or Salmonella is transmitted by formulations are equally effective. paratyphoid bacilli from the blood, urine or contaminated water and food and rarely Vaccination does not offer full protection faeces. Repeated sampling may be by direct contact. Water, ice (if unboiled from infection and travellers should be necessary. Serology in the form of the water used), raw vegetables, salads and advised to exercise care in selecting food Widal test is no longer routinely used. shellfish are important sources for and drink. 230 The blue book: Guidelines for the control of infectious diseases

No vaccine is available against If the patient is a food-handler or works in a Control of environment paratyphoid fever. profession that poses a high risk of A public health investigation is carried The community should be educated transferring infection to others, such as out to determine the most likely source about personal hygiene, especially health care workers, or child care workers, of infection. A history of travel to an thorough hand washing after toilet use they should be advised to cease work until endemic area is usually found. and before food preparation. advised by the Department. If there is no history of travel, local Control of case The Department arranges the collection sources of infection are investigated to Hospitalisation is usually required for and testing of weekly faecal specimens identify further cases, asymptomatic acute infections. for S. typhi or S. paratyphi to be taken over carriers, and contaminated food items. three consecutive weeks, commencing no Food industry Antibiotic therapy may include one or sooner than at least 48 hours after more to the following agents: If a case is involved in commercial food cessation of antibiotic treatment. Food preparation, the Department will ciprofloxacin, ceftriaxone, handlers and workers in high risk chloramphenicol, amoxycillin or co- determine the appropriate management professions are generally excluded from of the workplace on an individual basis. trimoxazole. However, strains resistant to high risk work or patient care until they chloramphenicol, amoxycillin and co- have had three consecutive negative Outbreak measures trimoxazole are common in south Asia. faecal specimens. All cases are intensively investigated, Failure to respond to ciprofloxacin has whether sporadic or part of a cluster. been reported from Vietnam. In the UK Control of contacts Further actions to reduce the risk of decreased susceptibility to ciprofloxacin Contacts should be educated about the infection during an outbreak may include: has been exhibited with increasing disease so as to reduce the risk of numbers of treatment failures particularly transmission and to allow for early • selective elimination of suspected in patients with a travel history to India identification if they develop symptoms. contaminated food and Pakistan. A similar picture is The decision to screen contacts of cases • ensuring pasteurisation of milk emerging in Victoria with ongoing S. typhi is dependent upon the extent of contact • ensuring appropriate chlorination or and S. paratyphi after treatment being and the likely source of the patient’s boiling of drinking water prior to noted. Consult the current version of infection. Faecal screening is generally consumption Therapeutic guidelines: antibiotic arranged for: (Therapeutic Guidelines Limited). • reviewing the integrity of waste and • Household contacts of a case who are sewerage systems. Education should be given to the patient food-handlers or in a high risk regarding the importance of completing profession. Screening is more intensive Widespread use of typhoid vaccine is not the course of antibiotics, the possibility and includes the entire household if generally recommended. of relapse, persisting excretion, the need the patient has no history of travel to a International measures for good personal hygiene and typhoid-endemic area. Typhoid vaccination is recommended for precautions in food preparation. • Fellow travellers. prolonged travel to endemic areas. Follow-up of all patients is conducted by Use of typhoid vaccine for contacts is Additional sources of information the Department of Human Services to not generally recommended. Typhoid • Skull, SA, Tallis, G 2001, ‘An evidence- identify possible sources of infection, vaccination is only recommended for based review of current guidelines for other cases, and to manage ongoing persons with intimate exposure to a the public health control of typhoid in risks. documented typhoid fever carrier, such Australia: a case for simplification and as occurs with continued household resource savings’, Aust N Z J Public contact. Health, vol. 25, no. 6, pp. 539–42. The blue book: Guidelines for the control of infectious diseases 231

Verotoxin producing E. coli (VTEC) (Enterohaemorrhagic E. coli [ETEC], Shiga-like toxin producing E. coli [STEC])

Victorian statutory requirement Method of diagnosis Since then several large outbreaks have Haemolytic uraemic syndrome (Group A Diagnosis is confirmed by isolation of the been reported worldwide and over disease) must be notified immediately by organism from faeces. Other diagnostic 70,000 cases are reported in the US telephone followed by written notification methods may be required including: each year. A particular brand of within five days. • demonstrating the presence of Shiga- fermented salami was implicated in a large outbreak in South Australia in 1995. VTEC and STEC (Group B disease) must like toxins be notified in writing within five days of • serotyping An average of five cases of VTEC and diagnosis. three cases of HUS are reported in • DNA probes that identify the toxin Victoria each year. This is likely to be a School exclusion: exclude if required by producing genes or the presence of significant underestimate of the true the Secretary and only for the period the VTEC virulence plasmid. burden of disease related to VTEC due to specified by the Secretary. Contacts are As screening for VTEC is not routine in the lack of routine screening of bloody not excluded. Victorian laboratories the test should be diarrhoea. Infectious agent specifically requested for persons with Reservoir Escherichia coli serotypes capable of bloody diarrhoea. The gastrointestinal tracts of cattle and producing toxins (Shiga-like or Vero- As a negative stool culture is not possibly other domesticated animals act toxins) similar to those of Shigella exclusionary, HUS should be considered as reservoirs. Humans serve as dysenteriae type 1 are the causative in the presence of the following: reservoirs for person to person agents. The most important are E. coli • acute microangiopathic anaemia on transmission. Prolonged carriage is O157:H7, E. coli O111:H8 and E. coli peripheral blood smear uncommon. O26:H11. • acute renal impairment (haematuria, Mode of transmission Identification proteinuria or elevated creatinine level) Ingestion of contaminated food and Clinical features • thrombocytopaenia, particularly during water and person to person and animal Illness is characterised by severe the first seven days of illness. to person transmission by the faecal-oral abdominal pain and cramping and watery route are responsible for VTEC infection. diarrhoea which becomes grossly bloody Incubation period Undercooked meat, especially ground and lasts five to ten days. Fever is usually The incubation period is two to eight meat or mince, is a source of infection. mild or absent. Asymptomatic infection days, with an average of three to four Other known food sources have included can occur. days. lettuce, sprouts, salami, unpasteurised In children aged less than five years and Public health significance milk and fruit juices. The infectious dose the elderly, infection may lead to and occurrence necessary to cause disease is thought to haemolytic uraemic syndrome (HUS). Recognition of VTEC as an important be as low as ten organisms. This is a disease characterised by renal cause of food-borne illness is relatively failure, a high mortality rate and Period of communicability recent. The first outbreaks of O157:H7 thrombotic thrombocytopaenic purpura VTEC is communicable for as long as the were reported in the United Kingdom and (TTP). HUS and TTP are complications of organism is present in faeces which is United States in the early 1980s. infection with serotype O157:H7. approximately one week for adults but may be as long as three weeks in children. 232 The blue book: Guidelines for the control of infectious diseases

Susceptibility and resistance Children must not attend school or child Additional sources of information Everyone is susceptible to infection. care until diarrhoea has ceased. Any • Bettelheim, KA, Hornitzky, MA, Children and the elderly are at higher risk ongoing exclusion is at the discretion of Djordjevic, SP, Kuzevski, A 2003, for severe disease. Antibiotic resistance the Secretary of the Department of ‘Antibiotic resistance among is of increasing concern. A study recently Human Services. verocytotoxigenic Escherichia coli conducted in Melbourne found that 28% Control of contacts (VTEC) and non-VTEC isolated from of VTEC strains isolated from healthy The diagnosis should be considered in domestic animals and humans’, J Med babies, who had neither contact with symptomatic contacts. As for cases, Microbiol, vol. 52, pt 2, pp. 155–62. antibiotics nor had gastrointestinal work and school exclusion apply to • Karmali, MA 1989, ‘Infection by symptoms for at least two weeks prior to contacts with diarrhoea. verocytotoxin-producing Escherichia the specimen being taken, were resistant Control of environment coli’, Clinical Microbiological Review, to one or more of the antibiotics tested. Environmental surfaces exposed to vol. 2, no. 1, pp. 15–38. Control measures infectious material should be thoroughly • Subcommittee of the PHLS Advisory Preventive measures cleaned. Implicated food should be Committee on Gastrointestinal Avoid ingestion of inadequately cooked destroyed and contaminated water Infections 2000, ‘Guidelines for the meat and meat products, unpasteurised sources treated. control of infection with Vero cytotoxin milk and fruit juices, unwashed salad Particular attention to personal and producing Escherichia coli (VTEC)’, ingredients and untreated water. Hand environmental hygiene should be Commun Dis Public Health, vol. 3, no. washing before and after using the toilet observed in food premises, institutions 1, pp. 14–23. and preparing or eating food is critical. and child care centres. Control of case Outbreak measures Treatment is generally supportive, A single case of EHEC or HUS is particularly maintenance of hydration. potentially indicative of an outbreak. The role of antibiotics in the Search for other cases and identify management of VTEC is unclear and persons at risk of infection. A source of there is some concern that they may infection should be sought for all cases precipitate the onset of HUS. Specialist of EHEC and HUS. Obtain detailed food medical advice should be sought for and environmental exposure histories cases of HUS and TTP. Enteric from cases. Collect samples of precautions should be strictly observed potentially implicated food and send to in the management of hospitalised the Microbiological Diagnostic Unit for cases. analysis. Antibiotic prophylaxis has Food handlers, child care workers and neither been proven to be efficacious nor health care workers must not work until safe for the prevention of secondary symptoms have stopped and two cases during VTEC outbreaks. consecutive faecal specimens taken at Refer to the Department’s Guidelines for least 24 hours apart are negative for the investigation of gastrointestinal illness VTEC. for more detailed on the investigation and management of outbreaks. The blue book: Guidelines for the control of infectious diseases 233

Viral gastroenteritis (not rotavirus)

Victorian statutory requirement Incubation period person to person contact. Aerosols are Isolated cases are not notifiable. The incubation period is usually 24–48 thought to be important in the transmission of norovirus and it is also School exclusion: exclude from school or hours. The known range for norovirus is known to persist on certain childcare centres until after symptoms 10–50 hours. contaminated surfaces such as carpets have ceased or a medical certificate of Public health significance for weeks. recovery is produced. and occurrence Infectious agents The endemic burden of gastroenteritis of Period of communicability Communicability continues during the Small round structured viruses (SRSVs) viral causes is not known however acute phase and for as long as viral including noroviruses and other norovirus is recognised as the major shedding persists. Cases should be caliciviruses, astroviruses and cause of outbreaks of non-bacterial considered infectious until at least 48 adenoviruses are the infective agents. gastroenteritis. Explosive outbreaks have occurred in institutions, camps, childcare hours after diarrhoea has ceased. Identification centres, cruise ships, restaurants and Shedding of norovirus in the absence of Clinical features following catered functions. clinical illness can persist for up to two Illness is characterised by an acute onset Approximately 50% of gastroenteritis weeks and is of concern in food-handler of fever, myalgia, headache, nausea, outbreaks investigated each year in related transmission. vomiting, abdominal cramps and watery Victoria are attributed to viral pathogens. Susceptibility and resistance diarrhoea lasting 12–60 hours. Vomiting High secondary attack rates result in Everyone is susceptible to infection and is relatively more prevalent among outbreaks that are often prolonged and infection is not known to confer lifelong children. Forceful vomiting as a difficult to contain. immunity. predominant symptom and a significant Disease occurs in all age groups and secondary in an outbreak of predominantly affects infants and young Control measures gastroenteritis are suggestive of children. In Australia, viruses can be Preventive measures norovirus infection. Although rare, severe detected throughout the year but are Prevention is dependent on attention to dehydration caused by viral more common in the period from late good food and personal hygiene, gastroenteritis can be fatal in persons winter to early summer. Norovirus has particularly hand washing. with debilitating health conditions. been reported to account for between Control of case 5–17% of cases of diarrhoea in the Method of diagnosis Treatment is symptomatic and should be community and 5–7% of cases requiring Diagnosis is predominantly based on focussed on maintaining hydration. clinical presentation. Virus in stool can treatment by physicians. be visualised and distinguished by Healthcare workers and food handlers electron microscopy. Nucleic acid Reservoir should be excluded from work until at hybridisation assays and RT-PCR assays The reservoir is thought to be primarily least 48 hours after diarrhoea and to detect norovirus genome are a humans. vomiting has ceased. Children should be excluded from school or childcare sensitive and specific tool for outbreak Mode of transmission investigations. Nucleotide sequencing centres until after symptoms have Viral gastroenteritis is predominantly provides a classification of the viruses n ceased or a medical certificate of spread via the faecal-oral route. observed,and is an important tool in recovery is produced. Residents of Transmission is facilitated through establishing links to contaminated institutions should be isolated until contaminated food (particularly raw vehicles of infection in outbreak settings. diarrhoea has ceased. shellfish), water (including ice) and 234 The blue book: Guidelines for the control of infectious diseases

Control of contacts Advise case to maintain strict personal hygiene and hand washing in the home. Determine if others are ill. If so, report to Local Government environmental health officers or the Department’s Communicable Diseases Section so that outbreak investigation and control can occur. Control of environment The ability of norovirus to survive relatively high levels of chlorine and varying temperatures (from freezing to 60°C) means rigorous attention to clean- up procedures and personal and home hygiene is essential in preventing further transmission.

Outbreak measures An outbreak is defined as two or more related cases of gastroenteritis. The primary aim is to prevent further disease by identifying the source, cleaning contaminated environments and isolating cases. Special settings Specific protocols for the management of outbreaks in special settings are available from the Communicable Diseases Section of the Department of Human Services.

Additional sources of information Centres for Disease Control and Prevention 2001, ‘Norwalk-like viruses: public health consequences and outbreak management’, MMWR, vol. 50, RR9, pp. 1–18. The blue book: Guidelines for the control of infectious diseases 235

Viral haemorrhagic fevers

Victorian statutory requirement infections are complicated by massive • Marburg virus is usually three to nine Viral haemorrhagic fever (Group A haemorrhage and multi-organ failure. days disease) must be notified immediately by Case fatality rates vary greatly: • Ebola virus is usually 2–21 days. telephone or fax followed by written • Lassa fever virus has a case fatality notification within five days. Public health significance rate of 1% of infected cases but 25% of and occurrence School exclusion: until medical hospitalised cases. clearance. The term viral hemorrhagic fever (VHF) • Crimean-Congo haemorrhagic fever refers to a group of rare illnesses that are Crimean-Congo, Ebola, Lassa and virus has a case fatality rate of 2–50%. caused by several distinct families of Marburg viral haemorrhagic fevers are • Marburg virus has a case fatality rate viruses. While some types of subject to Australian quarantine. of 25% and Ebola virus is 50–90%. hemorrhagic fever viruses can cause relatively mild illnesses, many of these Infectious agent Method of diagnosis viruses cause severe life-threatening Four viral haemorrhagic fevers (VHFs) are The Department of Human Services and disease. of particular concern because they could the Victorian Infectious Diseases be imported into Australia and be Reference Laboratory (VIDRL) should be Lassa, Marburg and Ebola viruses are transmitted to other people, particularly consulted prior to the collection and restricted to sub-Saharan Africa. health care personnel by blood or body transport of any clinical specimens from Crimean-Congo haemorrhagic fever virus fluid inoculation. These quarantinable suspected VHF patients for diagnostic is more widely distributed in Africa, the VHFs are: testing. Mediterranean region, the Middle East, Eastern Europe, Central Asia and China. • Lassa fever (LF) virus - an arenavirus All suspected VHF clinical specimens are The origins of the Marburg and Ebola tested under the highest bio-security • Crimean-Congo haemorrhagic fever viruses are still unclear but most cases level (BSL–4) laboratory conditions. (CCHF) virus - a Bunyavirus appear to have arisen in Africa. Diagnosis is typically made using specific • Ebola virus (EV) and Marburg virus PCR tests supported by viral isolation The high case fatality rate means that it (MV) - filoviruses. and serology. Appropriate specimens is important that the diagnosis is made Dengue haemorrhagic fever and yellow are: and treatment is commenced as early as fever are discussed elsewhere. possible. Viral haemorrhagic fevers • unclotted blood, tissue or nose and should be considered in the differential throat swabs for viral PCR Identification diagnosis of every patient with an Clinical features • unclotted blood, urine, tissue or nose unexplained fever who has been exposed Clinically apparent infections with any of and throat swabs for virus isolation to the infection in an area with endemic these viruses may present with similar • clotted blood for serology. VHF during the preceding three weeks. symptoms. Fever is typically insidious in onset and accompanied by severe Incubation period Reservoir headache, myalgia and malaise. Other The incubation period varies according to The reservoir for Lassa fever virus is a symptoms include retrosternal chest pain, the causative agent: rodent known as the multimammate rat cough, abdominal pain, diarrhoea, of the genus Mastomys spp. • Lassa fever virus is usually 6–21 days conjunctivitis, facial swelling, proteinuria The reservoirs for Crimean-Congo • Crimean-Congo haemorrhagic fever and jaundice. A bleeding diathesis leads haemorrhagic fever virus are hares, birds virus is usually one to three days to mucosal bleeding, haematemesis, and Hyalomma spp. of . Domestic (range 1–12 days) melaena and haematuria. Severe animals such as sheep, goats and cattle 236 The blue book: Guidelines for the control of infectious diseases

may act as amplifying hosts. Period of communicability All patients should be cared for at the The of Ebola virus Communicability of viral haemorrhagic hospital where they are first seen (if remains unknown. Current evidence fevers depends on the infective agent: possible), or transferred to the Victorian Infectious Diseases Service at the Royal suggests that the virus is zoonotic • Lassa fever virus is communicable via Melbourne Hospital, the designated VHF (animal-borne) and is normally person to person spread during the treatment centre forVictoria, or similarly maintained in animal hosts native to the acute febrile phase. Virus is excreted in equipped tertiary hospital. African continent. This could include the urine for up to three to nine weeks other primates such as gorillas. from the onset of the illness. Intravenous ribavirin may be useful for treatment purposes; a stock of this drug • Crimean-Congo haemorrhagic fever Mode of transmission is maintained at a number of tertiary virus communicability is unknown. The Transmission for the viral haemorrhagic hospitals including the Royal Melbourne virus is highly infectious in the hospital fevers depends on the type of virus: Hospital. setting where it has been transmitted • The Mastomys rodents shed Lassa to health care personnel by accidental Cases should be cared for in an isolation fever virus in urine and droppings. The needle stick injury. room, preferably with negative pressure virus can be transmitted through direct ventilation, and non-essential staff and • Marburg and Ebola virus are contact with these materials, touching visitors should be restricted. The highest communicable as long as blood and objects or eating food contaminated level of barrier infection control secretions contain virus. Virus has with these materials, or through cuts or precautions should be instituted been isolated in seminal fluid 60 days sores. Person to person transmission including gowns, gloves, face shields and after the onset of infection. may occur through sexual contact or masks. inoculation with blood. Susceptibility and resistance No has been • Crimean-Congo haemorrhagic fever All ages are susceptible. The duration of reported so personal and room HEPA virus is transmitted by the bite of immunity after infection is unknown. filtration is not an absolute requirement infective Hyalomma spp. ticks. Ticks are but should be used if available. An Control measures believed to acquire the virus by anteroom for putting on and discarding Preventive measures transovarian transmission or from clothing and storing supplies is Not applicable in Australia. No vaccines animal hosts. Nosocomial spread to advisable. medical workers in contact with infected are available. The obligatory period of isolation for a blood or secretions has been observed. Intending travellers to LF and CCHF proven case of viral haemorrhagic fever Slaughtering of infected animals is also endemic areas should avoid contact with is a minimum of two days without fever linked to some infections. ticks and rodents. and a total of 21 days from onset of • The source of infection for the index Control of case illness. human for Ebola and Marburg viruses All travellers who arrive in Australia with Convalescent patients and their contacts is usually unknown. Secondary human any risk of contracting quarantinable VHF should be informed that VHF viruses may infections occur by person to person should be immediately notified to the be excreted for many weeks in semen spread through direct contact with Department of Human Services. (MV and EV) and in urine (LF). infected blood or secretions, including The Department of Human Services Meticulous personal hygiene is semen. Nosocomial transmission has state chief quarantine officer will make necessary. Abstinence from sexual also been reported through any decisions concerning patient’s intercourse is advised until genital fluids contaminated needles and syringes. assessment, transport and quarantine. have been shown to be free of the virus. The blue book: Guidelines for the control of infectious diseases 237

Post-mortem is discouraged. Bodies of self-surveillance as soon as VHF is immediately notify the Commonwealth deceased patients should preferably be considered to be a likely diagnosis in the Chief Medical Officer who would in turn cremated. index patient. notify WHO according to International Control of contacts Any close or high risk contact that Health Regulations, as well as notify the Active case and contact surveillance is develops a fever (> 38°C) or any other source country and other countries who conducted by the Department to identify symptoms of illness should be may receive possible exposure by any fellow cases and all contacts with immediately isolated and treated as a infected travellers. the patient from the 21 days after the VHF patient. Close and high risk contacts should be onset of symptoms. A contact is a Ribavirin may be prescribed as post- discouraged from travel during their person who has been exposed to an exposure prophylaxis for high risk period of surveillance. infected person or to an infected contacts of patients. person’s secretions or tissues within Additional sources of information three weeks of the patient’s onset of Control of environment • Australian Government Department of illness. All potentially contaminated personal Health and Ageing, quarantine and items and items used in the treatment of travel health information, Contacts are further classified as casual the patient should be disinfected with an http://www.health.gov.au contacts, close contacts or high risk appropriate viricide such as 0.5% • Centers for Disease Control and contacts. hypochlorite or 0.5% phenol with Prevention, Atlanta USA, Public health Casual contacts are those people with detergent, and as far as possible, emergency preparedness and response, no direct contact with the patient but subjected to heating by incineration, http://www.bt.cdc.gov who have been in the near vicinity, such autoclaving or boiling by appropriately as on the same aeroplane or in the same protected staff. Room disinfection should hotel. No special surveillance is required be performed using the same virucidal although information on the disease and disinfectants. symptoms may be distributed. These disinfection measures may apply Close contacts are defined as those to the patient’s place of residence and living with the patient, nursing and other environments where the patient hugging the patient, or handling the has spent a significant period of time patient’s laboratory specimens. If the while symptomatic, such as aircraft and diagnosis is confirmed, close contacts hotel rooms. are placed under self-surveillance with twice daily recording of body Outbreak measures temperature. A single case of any of these viral haemorrhagic fevers in any setting would High risk contacts are those with a constitute an outbreak and requires the history of either mucous membrane clinical and public health control contact with the patient (kissing, sexual measures as outlined above. intercourse), or needle-stick or other penetrating injuries contaminated with International measures blood or other body fluids from the In the event of a suspected or confirmed patient during their infectious period. case of any of these viral haemorrhagic These contacts should be placed under fevers, the Department would 238 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 239

Yellow fever

Victorian statutory requirement • stage three shows development of the Clinical evidence Yellow fever virus (Group A disease) must classic features of jaundice and Clinical evidence includes acute onset be notified immediately by telephone or haemorrhagic manifestations such as with fever and jaundice and other fax followed by written notification within epistaxis, haematemesis, melaena and possible manifestations of the disease. five days. uterine bleeding followed by Epidemiological evidence albuminuria, coma and death two to Any health care provider who suspects Epidemiological evidence includes a history three days later. yellow fever should immediately contact of travel to a yellow fever endemic country the Chief Quarantine Medical Officer. Method of diagnosis in the preceding six days and no history of The diagnosis is based on the presence vaccination with yellow fever vaccine in the School exclusion is not applicable. of laboratory, clinical and epidemiological preceding two months. Yellow fever is subject to Australian evidence. A person with a febrile illness who has quarantine. Laboratory evidence includes one of the been in a yellow fever area within the Infectious agent following: previous six days is considered a Yellow fever virus (YFV) is a member of • isolation of YFV from clinical material suspected case and should be reported the flavivirus group. immediately. • detection of YF viral RNA in clinical Identification material Incubation period Clinical features • seroconversion with a significant rise The incubation period is three to six Yellow fever is an acute viral disease of in IgG level to YFV days. short duration. In mild cases, the only • YFV specific IgM detected in the Public health significance symptoms may be headache and fever or absence of IgM to other flaviviruses. and occurrence a ‘dengue-like’ illness with fever, chills Yellow fever is endemic in tropical areas and myalgia. Sometimes the infection Yellow fever virus specific IgG on a single of South America and Central Africa. may be inapparent. specimen confirmed by neutralisation and where cross-reactions with other Outbreaks may occur in unaffected areas More severe disease occurs in a small flaviviruses have been excluded is if mosquitoes are infected by migrating percentage of cases and is characterised suggestive of infection and should be humans or monkeys infected with the by three stages: viewed in the context of clinical and virus. • stage one has fever, chills, backache, epidemiological evidence. Ae. aegypti is widely distributed in myalgia, nausea, vomiting and All clinical specimens should be Queensland. The introduction of yellow epistaxis. Faget’s sign of relative transferred immediately to the National fever virus to the Australian mosquito bradycardia with a high temperature High Security Quarantine Laboratory population could theoretically result in an with a slow pulse appears on the (NHSQL) at Victorian Infectious Diseases urban outbreak of human disease. No second day. On the third day the fever Reference Laboratory (VIDRL) as per other mosquito species in Australia are falls and the patient enters remission. national quarantine guidelines. VIDRL considered likely to be competent • stage two is a remission that may last should be contacted on (03) 9342 2600 vectors. several hours to several days. to discuss requirements for confirmatory Haemorrhages, anuria and delirium tests or for interpretation of laboratory may occur without remission. results. Cross-reactivity with other flaviviruses can occur. 240 The blue book: Guidelines for the control of infectious diseases

Reservoir Control measures Control of contacts In urban areas of endemic countries the Preventive measures If a traveller to Australia is diagnosed reservoirs are humans and Aedes All travellers to endemic areas in Africa with yellow fever and has been mosquitoes. In forest areas, invertebrates and South America should be potentially exposed to Australian Ae. (other than humans), mainly monkeys immunised. Certification of yellow fever aegypti mosquitoes during the period of and possibly marsupials, and forest vaccination is required for travellers over viraemia or if the first recognised case is mosquitoes are the reservoir. The one year of age entering Australia within indigenous, then the following measures viraemic period in monkeys and man is six days of leaving an infected country. should be considered: too short for monkeys to act as a A yellow fever vaccination certificate is Spray inside and around the home of the reservoir. valid for ten years and begins ten days patient, and all houses within a half a Humans have no essential role in after vaccination. Vaccine providers in kilometre radius, with an effective transmission of jungle yellow fever but Victoria must be accredited with the insecticide to eliminate vectors. Potential are the primary amplifying host (in the Department of Human Services. vector breeding sites should be urban cycle). Control of case destroyed, emptied or sprayed within this In Victoria suspected or confirmed cases area. Mode of transmission that require inpatient treatment should Contacts of the patient who have not Yellow fever is transmitted via infected be referred to the Victorian Infectious previously been immunised should be mosquitoes. Mosquitoes become Diseases Service at the Royal Melbourne offered yellow fever vaccine. Other cases infectious 9–12 days after a blood meal Hospital where adequate facilities for of mild febrile illness and any from a viraemic host. Human to human isolation are available if required. This is unexplained deaths possibly consistent transmission has not been documented. of particular concern in suspected cases with yellow fever should be investigated. where the differential diagnosis may Period of communicability Australian Quarantine and Inspection include other viral or haemorrhagic fevers Human blood is infective for mosquitoes Service officers routinely place travel with greater potential for person to shortly before the onset of fever and for companions of the case under person spread. three to five days after. Mosquitoes quarantine surveillance on entry into require nine to 12 days after a blood meal There are no endemic foci of yellow fever Australia for six days since last staying to become infectious and remain so for vectors in Victoria however infection of over night in a country where yellow life. Victorian mosquitoes is a theoretical risk. fever may be present. During this period Therefore, the case should be protected they are required to notify the Chief Susceptibility and resistance from exposure to mosquitoes for greater Quarantine Medical Officer if suffering Mild infections are common in endemic than five days after onset of infection. from a febrile illness. areas. Previous infection with dengue The case should be cared for in an Control of environment gives some degree of immunity, and isolation room or in a screened room Ae. aegypti mosquitoes should be passive immunity in infants born to with use of a mosquito net and a suitable eliminated near airports. Insect immune mothers may last for six months. knock down spray for mosquitoes if not quarantine should be maintained to Infections confer lifelong immunity. in hospital. prevent the introduction of Ae. albopictus, a prevalent Asian species which is capable of transmitting yellow fever. The blue book: Guidelines for the control of infectious diseases 241

Outbreak measures A single case of indigenous transmission constitutes an outbreak. In the event of an epidemic of yellow fever in an urban area, all persons living in the area infested with Ae. aegypti should be offered yellow fever vaccine and a wider mosquito spraying and breeding site elimination program implemented.

International measures Yellow fever must be notified to the World Health Organization under the International Health Regulations (1969).

Additional sources of information • Australian Government Department of Health and Aged Care 1999, Guidelines for the management of human quarantine disease in Australia. • Victorian Department of Human Services, for information on yellow fever vaccination clinics in Victoria phone the Immunisation Unit 1300 882 008 or go to www.health.vic.gov.au/ideas. • World Health Organization, http://www.who.int/emc/topics 242 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 243

Appendix 1: Contacts

Organisation Telephone Fax Internet After hours contact

Department of Human Services, Victoria

Communicable Diseases Section 1300 651 160 (03) 9637 4477 www.health.vic.gov.au/ideas 132222 (03) 9637 4126 general www.betterhealth.vic.gov.au pager no. 46870 1300 651 170 for notifications

Melbourne Sexual Health Centre (03) 9347 0244 (03) 9347 2230 www.mshc.org.au

Laboratories

Microbiological Diagnostic Unit (03) 9344 5713 (03) 9344 7833 www.microbiol.unimelb.edu.au

Victorian Infectious Diseases (03) 9342 2600 (03) 9342 2666 www.vidrl.org.au (03) 9342 2600 Reference Laboratory

Interstate health departments

Australian Capital Territory: (02) 6205 2155 (02) 6205 0711 www.health.act.gov.au Pager Communicable Disease Control (02) 6269 0495

New South Wales (02) 9391 9000 (02) 9391 9101 www.health.nsw.gov.au

Northern Territory: Disease Control (08) 8922 8044 (08) 8922 8310 www.nt.gov.au/health Hospital switchboard (08) 8922 8888

Queensland: Communicable (07) 3234 1155 (07) 3234 0057 www.health.qld.gov.au Diseases Unit

South Australia: Communicable (08) 8226 7177 (08) 8226 7187 www.health.sa.gov.au (08) 8226 7177 Disease Control

Tasmania: Public and Environmental 1800 671 738 (03) 6222 7407 www.dhhs.tas.gov.au 1800 671 738 Health Services (03) 6233 3203

Western Australia: Communicable (08) 9388 4999 (08) 9388 4888 www.population.health.wa.gov.au (08) 9388 4999 Disease Control

Other government departments

Food Standards Australia (02) 6271 2222 (02) 6271 2278 www.foodstandards.gov.au New Zealand

Australian Government Department (02) 6289 1555 (02) 6281 6946 www.health.gov.au (02) 6122 2747 of Health and Ageing

Victorian Department of 136 186 www.dpi.vic.gov.au Primary Industries 244 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 245

Appendix 2: Glossary airborne transmission droplet transmission infectious agent Transmission by air of infectious agents Transmission of infectious agents in An organism that is capable of producing from respiratory secretions. droplets from respiratory secretions. infection or infectious disease. asymptomatic infection endemic infestation Infection that does not display any The constant presence of a disease or The lodgement, development and clinical symptoms, but may still be infectious agent within a given reproduction of arthropods on the capable of transmitting disease. geographic area. surface of the body of persons or animals carrier epidemic or in clothing. A person or animal that harbours a The occurrence of a number of cases of isolation specific infectious agent in the absence a disease (or condition) in excess of a Represents separation for the period of of clinical disease and serves as a number expected in a given time and communicability, of infected persons or potential source of infection. place. In some instances a single case animals from others in such places and communicable disease will constitute such an unusual under such conditions as to prevent or A disease capable of being transmitted occurrence. limit the direct or indirect transmission of from an infected person or species to a fomes (plural fomites) the infectious agent. Categories of susceptible host, either directly or An object such as a book, wooden isolation include: indirectly. object, or an article of clothing that is not • strict isolation: for highly contagious concurrent disinfection harmful in itself, but is able to harbour infections spread by air and contact Immediate disinfection and disposal of pathogenic microorganisms and thus • contact isolation: for diseases spread discharges and infective matter all may serve as an agent of transmission of primarily by close or direct contact an infection. through the course of a disease. • respiratory isolation: to prevent contact immunity transmission over short distances A person or animal that has associated The protection against infectious disease through the air. generated by immunisation, previous with an infected person or animal that For drainage/secretion precautions see might provide an opportunity to acquire infection or by other nonimmunologic factors. separate entry. For blood and body the infection. substance precautions, see appendix 3. disinfection inapparent infection The presence of infection in a host nosocomial infection Killing of infectious agents outside the Hospital-acquired infection. body by direct exposure to chemical or without recognisable clinical signs or physical agents. High level disinfection symptoms. notifiable disease refers to the inactivation of all incubation period Disease or condition that is required by microorganisms except some bacterial The time interval between initial contact law to be notified to the State health spores. with an infectious agent and the department. drainage/secretion precautions appearance of clinical signs and notification Precautions used to prevent infections symptoms. The process of reporting a notifiable transmitted by direct or indirect contact infection infectious disease. with purulent material or drainage from Invasion and multiplication of micro- outbreak an infected body site. organisms in body tissues. See epidemic. 246 The blue book: Guidelines for the control of infectious diseases

period of communicability surveillance The time during which an infectious Personal surveillance is the practice of agent may be transferred directly or close medical or other supervision of indirectly from an infected person or contacts to permit prompt recognition of animal to a susceptible host. infection or illness but without restricting personal hygiene the movements of the individual. The protective measures within the susceptibility responsibility of the individual that limit Lack of resistance to a particular the spread of infectious diseases. pathogenic agent. personal protective equipment transmission The equipment to be worn when In terms of infection, it relates to any performing duties that may involve mechanism by which an infectious agent possible occupational exposure to blood, is spread from a source or reservoir to a splashing or aerosols from cleaning person. This may be direct or indirect processes – for example, masks, goggles, (that is, vehicle-borne, vector-borne, or gloves and aprons. airborne). quarantine standard precautions The restriction of freedom of movement Work practices that require everyone to of apparently healthy individuals who assume that all blood and body fluids are have been exposed to infectious disease. potential sources of infection, reservoir of infectious agents independent of perceived risk. Such Any person, animal, or substance in precautions involve the use of safe work which an infectious agent normally lives practices and protective barriers, and the and multiplies in such a manner that it safe disposal of body substances and can be transmitted to a susceptible host. soiled material. See appendix 3. resistance vector The natural ability of an organism to A carrier, especially the animal (usually resist micro-organisms or toxins an arthropod) that transfers an infective produced in disease. agent from one host to another. school exclusion Exclusion from school or children’s A disease of animals that may be services centre under Health (Infectious transmitted to humans under natural Diseases) Regulations 2001. conditions. source of infection The person, animal or substance from which an infectious agent passes to a host. The blue book: Guidelines for the control of infectious diseases 247

Appendix 3: Standard and additional precautions

General Standard precautions should be Standard precautions for infection Infection control and prevention uses a implemented at all times particularly control in health care settings consist of risk management approach to minimise when patients are undergoing invasive the following work practices: or prevent the transmission of infection. procedures, including catheterisation, • aseptic technique for all invasive Standard and additional precautions cannulation or intubation. Health procedures, including appropriate use principles and practice are based on the services that offer these procedures of skin disinfectants mode of transmission of an infectious should provide detailed protocols for • personal hygiene practices, particularly agent. patient management in their infection control procedures manuals. hand washing and drying before and Standard precautions are work practices after all significant patient contacts required for the basic level of infection Additional precautions are work practices • the use of 70% alcohol-based control. They include good hygiene that should be applied in a health care chlorhexidine (0.5%) hand rub solutions practices, particularly washing and setting for patients known, or suspected, as an adjunct to hand washing drying hands before and after patient to be infected or colonised with contact, the use of protective barriers infectious agents that may not be • use of personal protective equipment, which may include gloves, gowns, plastic contained using standard precautions which may include gloves, aprons, masks, eye shields or goggles, alone. impermeable gowns, plastic aprons, appropriate handling and disposal of masks/face shields and eye protection Standard precautions sharps and other contaminated or clinical • appropriate handling and disposal of The use of standard precautions is (infectious) waste, and use of aseptic sharps and other clinical (infectious) essential as the primary strategy for the techniques. waste successful minimisation of transmission Standard precautions apply to all of health care associated infection • appropriate reprocessing of reusable patients regardless of their diagnosis or because: equipment and instruments, including presumed infection status, and in the appropriate use of disinfectants handling of: • infectious patients may not show any signs or symptoms of infection that • environmental controls, including • blood may be detected in a routine history design and maintenance of premises, • all other body fluids, secretions and and medical assessment cleaning and spills management including appropriate use of excretions (except sweat), regardless • a patient’s infectious status is often disinfectants of whether they contain visible blood determined by laboratory tests that • non-intact skin may not be completed in time to • appropriate provision of support services such as laundry and food • mucous membranes (mouth and eyes) provide emergency care services. • standard precautions also apply to • patients may be infectious before dried blood and other body laboratory tests are positive or Additional precautions substances, including saliva. symptoms of disease are recognised Additional Precautions are used for (the window period of disease) Standard precautions should be patients known or suspected to be considered minimum requirements for • people may be placed at risk of infected or colonised with infection control. Implementing standard infection from those who are epidemiologically important or highly precautions minimises the risk of asymptomatic but infectious. transmissible pathogens that can transmission of infection from person to transmit/cause infection by the following person even in high-risk situations. means: 248 The blue book: Guidelines for the control of infectious diseases

• airborne transmission (e.g. pulmonary Additional precautions should be tailored Additional precautions are not required tuberculosis, chickenpox, measles) to the particular infectious agent involved for patients with bloodborne viruses, • droplet transmission of respiratory and the mode of transmission, and may such as HIV, hepatitis B virus or hepatitis secretions (e.g. rubella, pertussis, include one or any combination of the C virus, unless there are complicating influenza) following: infections, such as pulmonary tuberculosis. • contact transmission (direct or indirect) • allocation of a single room with ensuite with patients who may be facilities To minimise the exposure time of other disseminators of infectious agents of • a dedicated toilet (to prevent people in office practices or hospital special concern (e.g. the dry skin of transmission of infections that are waiting rooms, people identified as ‘at those colonised with Multi-resistant transmitted primarily by contact with risk’ of transmitting droplet or airborne Staphylococcus aureus [MRSA], faecal faecal material, such as for patients diseases (e.g. a child with suspected contamination from carriers of with infectious diarrhoea or chicken pox) should be subject to vancomycin-resistant enterococci gastroenteritis caused by enteric additional precautions including isolation [VRE] or contaminated surfaces) bacteria or viruses) and should be attended to before other people waiting for treatment. • inherent resistance to standard • cohorting (room sharing by people with sterilisation procedures or other the same infection) may be an An outline of the application of additional disease-specific means of transmission alternative if single rooms are not precautions for infections with airborne, where standard precautions are not available droplet or contact transmission is shown in the following table. sufficient (e.g. patients with known or • special ventilation requirements (e.g. suspected Creutzfeldt-Jakob disease) monitored negative air pressure in • any combination of these routes. relation to surrounding areas) Additional precautions are designed to • additional use of personal protective interrupt transmission of infection by equipment (e.g. health care workers these routes and should be used, in attending to patients in respiratory addition to standard precautions, when isolation should wear a well-fitting standard precautions alone might not mask: a 0.3-mm particulate filter mask contain transmission of infection. (P2 or N95 mask) is recommended for Additional precautions may be specific to tuberculosis) the situation for which they are required, • rostering of immune health care or may be combined where workers to care for certain classes of microorganisms have multiple routes of infectious patients (eg chickenpox) transmission. • dedicated patient equipment • restricted movement of both patients and health care workers. The blue book: Guidelines for the control of infectious diseases 249

Outline of requirements for specified categories of additional precautions Requirement Additional precautions by transmission route Airborne Droplet Contact Gloves Nil Nil For all manual contact with patient, associated devices and immediate environmental surfaces Impermeable apron/gown Nil Nil When health care worker’s clothing is in substantial contact with the patient, items in contact with the patient, and their immediate environment Respirator or mask. P2/N95 particulate Yes —mask* Protect face if splash likely respirator for Refer to AS 4381:2000 for tuberculosis only. additional information All others, use face mask suited to the purpose such as a mask that filters to o.1 microns and has a splash resistant shield. Goggles/face-shields Protect face if splash likely Protect face if splash likely Protect face if splash likely Special handling of equipment As per standard precautions As per standard precautions Single use or reprocess before reuse on next patient (includes all equipment in contact with patient) Single room Yes Yes If possible, or cohort with patient or or with the same infection (eg Cohort patients with Cohort patients methicillin-resistant Staphylococcus same infection. with same infection. aureus)

Door closed. Door closed. Negative pressure Essential for pulmonary TB No No Transport of patients Appropriate mask* Appropriate mask* Notify area receiving patient for patient for patient Notify area receiving patient Notify area receiving patient Other Encourage patients to cover Provide one metre of Remove gloves and gown, and nose and mouth when separation between patients wash hands before leaving coughing or sneezing and in ward accommodation patient’s room wash their hands after blowing nose.

Provide one metre of separation between patients in ward accommodation * Refer to Australian Standards: AS 4381:2000 Single-use face masks for use in health care, for additional information AS/NZS 1715 Selection, use and maintenance of respiratory protective devices AS/NZS 1716:1994 Respiratory protective devices 250 The blue book: Guidelines for the control of infectious diseases

Handwashing Gloves • Remove the used gown as promptly as • Wash and dry hands after touching • Wear gloves (clean non sterile gloves possible using gloved hands, roll up blood, body fluids, secretions, are adequate) when touching blood, carefully and place in a linen excretions and contaminated items body fluids, secretions, excretions and receptacle for laundering. such as equipment or instruments, contaminated items; put on clean • Wash and dry hands to avoid transfer regardless of whether gloves are worn gloves just before touching mucous of microorganisms to other patients or not. membrane and non-intact skin. Sterile and environments. • Wash and dry hands immediately after gloves are required for invasive gloves are removed, after significant procedures. Masks, eye protection, patient contact such as contact with or • Change gloves between tasks and faceshields physical examination, emptying procedures on the same patient after Wear a mask and eye protection or a drainage bags, undertaking contact with material that may contain faceshield to protect mucous venepuncture or delivery of an a high concentration of membranes of the eyes, nose and injection or going to the toilet. microorganisms. mouth: • Wash and dry hands following any • Remove gloves promptly after use, • during procedures and patient-care activities that may transfer before touching non-contaminated activities that are likely to generate microorganisms to other patients or items and environmental surfaces and splashes or sprays of blood, body environments. before going to another patient. fluids, secretions and excretions • Use plain liquid soap for routine hand Dispose of gloves in the clinical • during cleaning activities. washing. Antimicrobial liquid soap (infectious) waste or place in a plastic Remove the mask by holding the ties solutions are required for invasive bag and tie before disposing of it in the only and dispose of the mask into a procedures and in some situations general household waste. clinical waste bin. such as those patients with VRE and • Wash and dry hands immediately after Reusable face shields or goggles should MRSA. removing gloves to avoid transfer of be removed carefully and placed in a • A 70% alcohol-based chlorhexidine microorganisms to other patients or receptacle for cleaning. (0.5%) hand rub solution may be used environments. Waterproof aprons as an adjunct to handwashing and in Gowns situations where water is not readily Wear waterproof aprons when splashes • Wear a gown (a clean non-sterile gown available. or sprays of blood or body fluids/ is adequate) to protect skin and substances are likely such as during Personal protective equipment prevent soiling of clothing during cleaning activities. procedures and patient care activities The use of personal protective Remove the used apron as promptly as that are likely to generate splashing or equipment (PPE) protects the health care possible using gloved hands, roll up sprays of blood, body fluids, worker and others from exposure to carefully and place in a clinical waste bin. blood and body fluids/substances. PPE secretions, or excretions or cause that complies with relevant Australian soiling of clothing. Standards should be readily available • Select a gown (long- or short –sleeved) and accessible in all health services. that is appropriate for the activity and the amount of fluid likely to be encountered. The blue book: Guidelines for the control of infectious diseases 251

Environmental control Further information Ensure that the health service has • Australian Government Department of adequate procedures for the routine Health and Ageing 2004, Infection care, cleaning, and disinfection of control guidelines for the prevention of environmental surfaces, beds, bedrails, transmission of infectious diseases in bedside equipment, and other frequently the health care setting, touched surfaces and that these http://www.icg.health.gov.au/ procedures are being followed. See • Victorian Department of Human Appendix 6 for cleaning and waste Services 2000, Sure protection against disposal. infection, www.health.vic.gov.au/ideas 252 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 253

Appendix 4: Procedure for managing an exposure to blood/body fluids/substances

These include sharps injuries (including incidents involving either patients or Patients or others exposed to blood or needlestick) and splashes into/onto health care workers, including: other body fluids/substances must be mucous membranes or bare intact skin. • the physician, medical officer or other informed of the exposure by a Occupational hazards for health care suitably qualified professional to be designated professional, while workers from sharps injuries (including contacted maintaining confidentiality about the needlestick injury) and other blood or source of the blood. Baseline serum • the laboratory which will process should be collected from the patient and body fluid incidents include human emergency specimens immunodeficiency virus (HIV), hepatitis B expert counselling provided on the virus (HBV) and hepatitis C virus. • the pharmacy which stocks implications of what has happened. prophylactic medication Postexposure prophylaxis (PEP and N- Exposure is an injury that involves direct • procedures for investigating the PEP) and appropriate long-term follow-up skin contact with a body fluid listed above should be offered where applicable. and there is compromised skin integrity circumstances of the incident and measures to prevent recurrence (this Patient or source refusal for testing and such as an open wound, abrasion or serum storage should be documented. dermatitis, or if there is direct mucous may include changes to work membrane contact. For exposure to skin, practices, changes to equipment, Australian National Council for AIDS, the larger the area of skin exposed and the and/or training) Hepatitis C and Related Diseases longer the time of contact, the more • details for prompt reporting, evaluation, (ANCAHRD) has published a important it is to verify that all the relevant counselling, treatment and follow-up of comprehensive bulletin entitled skin area is intact. occupational exposures to bloodborne Management of exposure to blood/body viruses. fluids in a health care setting, available at Exposure to blood and body http://www.ancahrd.org/. fluids/substances Immediate action Document the incident and include: The following body fluids pose a risk for Treatment protocols should include • date, time and type of exposure bloodborne virus transmission: removal of contaminated clothing and • how the incident occurred • blood, serum, plasma and all biological thorough washing of the injured area fluids visibly contaminated with blood with soap and water. Affected mucous • name of the source individual membranes should be flushed with large (if known) • laboratory specimens that contain amounts of water. Eyes should be Exposure incidents that do not occur in a concentrated virus flushed gently. health service should be reported to a • pleural, amniotic, pericardial, The exposed person must report any general medical practitioner or the peritoneal, synovial and cerebrospinal occupational exposures immediately. Emergency Department at the nearest fluids The exposed person should have a hospital. • uterine/vaginal secretions or semen. medical evaluation, including information Management of the source Infection control protocols about medications they are taking and underlying medical conditions or individual All health services must develop their circumstances. Postexposure prophylaxis The person whose blood or body fluids own infection control protocols for (PEP and N-PEP) and counselling should are the source of an occupational/ communicable diseases, including clear be available and offered. Treatment non-occupational exposure or other written instructions on the appropriate should be available during all working injury should be evaluated for infection action to take in the event of an hours, and on call after hours (e.g. with HIV, HBV and HCV. Information exposure to blood or body through an on-call infectious diseases available in the medical record or from fluids/substances including needlestick physician). the source person may suggest or rule injuries and other blood or body fluid 254 The blue book: Guidelines for the control of infectious diseases

out infection with each virus. If the Source individual unknown Depending on the circumstances of the source is known to have HIV infection, Reasonable efforts should be made to exposure, the following may need to be then information on stage of infection identify the source. If the source remains considered: and current and previous antiretroviral unknown, appropriate follow-up should • tetanus immunoglobulin therapy should be gathered and used in be determined on an individual basis • a course of adsorbed diphtheria deciding the most appropriate regimen of depending on: post exposure prophylaxis (PEP). tetanus vaccine, adult formulation (Td) • the type of exposure vaccine If the HIV, HBV or HCV status of the • the likelihood of the source being source person is unknown, then the • Td booster. positive for a blood pathogen source person should be informed of the The current edition of The Australian incident, and their consent sought to test • the prevalence of HIV, HBV and HCV in immunisation handbook should be for these viruses, with appropriate pre- the community of the likely source on consulted for further details. whom the instrument or needle was and post-test counselling. Their consent The exposed person would normally be used. to having the information in their patient tested for HIV antibody, HCV antibody record used should be sought also. If Management of the exposed and antibody to HBV surface antigen consent cannot be obtained, for example person (HBsAg) at the time of the injury, to if the patient is unconscious or unwilling Immediate care of the exposure site establish their serostatus at the time of to consent, then procedures should be Contaminated clothing should be the exposure. Expert counselling on the followed which comply with legislation in removed, and the injured area should be implications of the event, PEP (post Victoria. washed well with soap and water (an exposure prophylaxis) and appropriate The source individual should be tested as antiseptic could also be applied). Any long-term follow-up should be offered. follows at the time of injury: affected mucous membranes should be An option that may be offered to health • HIV antibody flushed with large amounts of water. If care workers who do not wish to undergo the eyes are contaminated, they should • HBsAg testing at the time of the exposure is to be rinsed gently but thoroughly with have blood collected and stored but not • HCV antibody. water or normal saline, while kept open. tested. Blood that is collected and stored If the HCV antibody test is positive, then Evaluation of the exposure for this purpose must be retained for a HCV polymerase chain reaction (PCR) The exposed person should be examined minimum period of 12 months. should be performed to test for HCV to confirm the nature of exposure and If the source person is found to be HIV, RNA. Transmission is much less likely to counselled about the possibility of HBV and HCV negative, no further follow- occur from a source who is PCR transmission of bloodborne disease. up of the exposed person is generally negative. The status of the source Evaluation and testing of the exposed necessary, unless there is reason to individual may be known at the time of person suspect the source person is the incident. In this case the affected The exposed person should have a seroconverting to one of these viruses, person should be managed as described medical evaluation, including information or was at high risk of bloodborne viral below under ‘immediate management’. If about medications they are taking and infection at the time of the exposure. If the source is unknown, the case should underlying medical conditions or source is positive for one of these be managed as described below. circumstances. All exposed people viruses, pregnancy testing should be should be assessed to determine the risk offered to women of child-bearing age of tetanus. who have been exposed and whose pregnancy status is unknown. The blue book: Guidelines for the control of infectious diseases 255

Postexposure counselling Management of exposure to blood/body fluids summary table A specialist with knowledge of When What bloodborne infections should undertake Immediately after exposure First aid follow-up. If it is demonstrated that a Relief from duty person has been exposed to a Risk assessment bloodborne pathogen, they should not Post exposure prophylaxis (PEP) – if significant injury donate blood, semen, organs or tissue for As soon as possible Source assessment six months, and should not share (same day) Documentation of exposure implements that may be contaminated Prevention of transmission and exposure/pre-test counselling with even a small amount of blood (e.g. Baseline serology if agreed to razors or toothbrushes). Referral to specialist physician - if PEP commenced Support of significant others For HIV and HBV, they should be 1-3 weeks Post-test counselling with results of baseline serology informed of the risk of transmission to Occupational health and safety review sexual and injecting partners for a six- month period, and be counselled about 3 months Pre HIV test counselling Follow up serology – HIV, HBV, HCV issues of safe sex and safe injecting. If PEP is indicated, or there is a risk of 6 months Follow up serology – HBV, HCV acute infection with HIV, HCV or HBV, – HIV (if PEP taken) advice should be offered on pregnancy and breastfeeding based on an individual risk assessment. In the case of HIV, patients should be advised of the remote risk of seroconversion up to 12 months post-exposure, particularly if specific PEP was undertaken. Follow-up for the exposed person If the source person is seronegative for HIV, HbsAg and HCV, baseline testing or further follow-up of the health care worker normally is not necessary. If the source person has recently engaged in behaviours that are associated with a risk for transmission of these viruses, baseline and follow-up HIV-antibody testing of the health care worker should be considered. 256 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 257

Appendix 5: Procedure for managing spills of blood and body fluids/substances

Health services should have service, in a public location or within a from the disinfectant granules, or management systems in place for dealing community premises aerosols, which may be generated from with blood and body substance spills and • whether there is any likelihood of bare high-risk spills during the cleaning protocols should be included in skin contact with the soiled process). procedural manuals and emphasised in (contaminated) surface. Single-use items in the spills kit should ongoing education or training programs. be replaced after each use of the spills The basic principles of blood and body Equipment kit. fluid/substance spills management are: Standard cleaning equipment, including With all spills management protocols, it is a mop and cleaning bucket and cleaning • standard precautions apply, including essential that the affected area is left agents, should be readily available for use of personal protective equipment clean and dry. (PPE) as applicable spills management and should be stored in an area known to all. This is Sodium hydroxide (caustic soda) spills • spills should be cleared up before the particularly important in clinical areas. To kits should be available for areas at risk area is cleaned (adding cleaning liquids facilitate the management of spills in for higher-risk CJD spills, such as to spills increases the size of the spill areas where cleaning materials may not neurosurgery units, mortuaries and and should be avoided) be readily available, a disposable ‘spills laboratories. • generation of aerosols from spilled kit’ could be used, containing the material should be avoided. following items: Procedures In clinical areas blood and body Using these basic principles, the • a large (10 L) reusable plastic fluid/substance spills should be dealt management of spills should be flexible container or bucket with fitted lid, with as soon as possible. In operating enough to cope with different types of containing the following items rooms, or in circumstances where spills, taking into account the following • appropriate leak proof bags and medical procedures are under way, spills factors: containers for disposal of waste should be attended to as soon as it is • the nature (type) of the spill (e.g. material safe to do so. sputum, vomit, faeces, urine, blood or • a designated, sturdy scraper and pan Care should be taken to thoroughly clean laboratory culture) for spills (similar to a ‘pooper scooper’) and dry areas where there is any • the pathogens most likely to be • about five sachets of a granular possibility of bare skin contact with the involved in these different types of formulation containing 10,000 ppm surface (e.g. on an examination couch). spills (e.g. stool samples may contain available chlorine or equivalent (each Personal protective equipment (PPE) viruses, bacteria or protozoan sachet should contain sufficient should be used for all cleaning pathogens whereas sputum may granules to cover a 10-cm diameter procedures and disposed of or sent for contain Mycobacterium tuberculosis) spill) cleaning after use. Hands should be • the size of the spill (e.g. spot [few • disposable rubber gloves suitable for washed and dried after cleaning. drops], small [<10cm] or large [>10cm]) cleaning (vinyl gloves are not Where a spill occurs on a carpet, • the type of surface (e.g. carpet or recommended for handling blood) shampoo as soon as possible. Do not impervious flooring) • eye protection (disposable or reusable) use disinfectant. Steam cleaning may be • the location involved i.e. whether the used instead. • a plastic apron spill occurs in a contained area such Wash hands thoroughly after cleaning is as a microbiology laboratory or in a • a respiratory protection device (for completed. public or clinical area of a health protection against inhalation of powder 258 The blue book: Guidelines for the control of infectious diseases

Spots or small spills Use of sodium hypochlorite (bleach) Spots or drops of blood or other small It is generally unnecessary to use sodium spills (up to 10cms) can easily be hypochlorite for managing spills but it managed by wiping the area immediately may be used in specific circumstances. with paper towelling and then cleaning It is recognised, however, that some with warm water and detergent followed health care workers/members of the by rinsing and drying the area. Dry the public may feel more reassured that the area as wet areas attract contaminants. risk of infection is reduced if sodium A hospital grade disinfectant can be hypochlorite is used. Health care workers used on the spill area after cleaning. and members of the public should be aware that there is no evidence of Large spills benefit from an infection control Where large spills (over 10cms) have perspective. occurred in a ‘wet’ area, such as a bathroom or toilet area, the spill should Hypochlorites are corrosive to metals be carefully washed off into the and must be rinsed off after 10 minutes sewerage system using copious amounts and the area dried. of water and the area flushed with warm Creutzfeldt–Jakob disease (CJD) water and detergent. If a spill of tissue (potentially) infected Large blood spills that have occurred in with Creutzfeldt–Jakob disease (CJD) ‘dry’ areas (such as clinical areas) should occurs (eg brain tissue), the be contained and generation of aerosols contaminated item should either be should be avoided. destroyed by incineration or immersed in either sodium hydroxide or sodium Granular formulations that produce high hypochlorite for one hour, rinsed and available chlorine concentrations can placed in a pan of clean water and contain the spilled material and are sterilised on an eighteen minute cycle. useful for preventing aerosols. A scraper The items should then be cleaned and pan should be used to remove the following routine cleaning and absorbed material. The area of the spill sterilisation procedures. should then be cleaned with a mop and bucket of warm water and detergent. The Surface spills should be cleaned up using bucket and mop should be thoroughly paper towels before the surface is wiped cleaned after use and stored dry. over with either sodium hydroxide or sodium hypochlorite, left for one hour (if possible or as long as possible, with the area cordoned off), the solution wiped off and the surface cleaned by following routine cleaning procedures. The blue book: Guidelines for the control of infectious diseases 259

Appendix 6: Cleaning and waste disposal procedures

Cleaning • detergents should not be mixed with dried before, and after, each session or General other chemicals when visibly soiled. Spills should be Cleaning is important particularly in work • all cleaning solutions should be cleaned up as soon as practical. areas because deposits of dust, soil and prepared fresh before use. • When a disinfectant is required for microbes on surfaces can transmit Specific surface cleaning, the manufacturer’s infection. Contaminated areas such as Surface cleaning recommendations for use and OH&S operating rooms or isolation rooms must • Floors in hospitals and day care instructions should be followed. be cleaned after each session and spot facilities should be cleaned daily, or as • Buckets should be emptied after use, cleaned after each case or thoroughly necessary, with a vacuum cleaner washed with detergent and warm cleaned as necessary. fitted with a particulate-retaining filter, water, rinsed in hot water and stored The following basic principles should be which should be changed in dry - turn upside down. followed: accordance with the manufacturer’s • Mops should be laundered or cleaned • written cleaning protocols should be instructions. in detergent and warm water, rinsed in prepared, including methods and • The exhaust air should be directed hot water then stored dry. Mop heads frequency of cleaning. These should away from the floor to avoid dust should be detachable or stored with include policies for the supply of all dispersal. mop head uppermost. cleaning and disinfectant products • A ducted vacuum cleaning system can Specialised areas • standard precautions (including also be used, as long as safe venting of • Isolation rooms and ensuite bathrooms wearing of personal protective the exhaust air is ensured. should be cleaned at least twice daily equipment as applicable) should be • Damp dusting is essential using a lint dependant on the type of organism. implemented when cleaning surfaces free cloth. Brooms disperse dust and • Operating rooms and day procedure and facilities (see appendix 3) bacteria into the air and should not be rooms including endoscopy rooms • cleaning methods should avoid used in patient/clinical areas. Dust- should be cleaned after each operating generation of aerosols retaining mops, which are specially session and when visibly soiled. • all cleaning items should be changed treated or manufactured to attract and Thorough cleaning of the operating after each use and cleaned and dried retain dust particles, do not increase suite should be performed daily in before being used again. They should airborne counts as much as ordinary addition to the cleaning performed also be changed immediately following brooms and remove more dust from after each operating session. the cleaning of blood or body surfaces (Ayliffe et al 1999). However, • Obstetric areas, particularly delivery fluid/substance spills, cleaned and brooms and dust-retaining mops suites should be cleaned after each dried. Single use cleaning items are should not be used in clinical areas delivery, when visibly soiled and at preferred where possible such as where there is a high risk of infection least daily. cleaning cloths which should be lint associated with dust (e.g. burns units). • Oncology areas should be cleaned free Procedure for routine surface cleaning twice daily. • sprays should not be used as they can • All cleaning solutions should be • Sterilising processing departments become contaminated and are difficult prepared immediately prior to use. (SSDs) should be cleaned at least to clean. Sprays are not effective as • Work surfaces should be cleaned twice daily and when visibly soiled. they do not touch all parts of the (wiped over) with a neutral detergent surface to be cleaned and warm water solution, rinsed and 260 The blue book: Guidelines for the control of infectious diseases

Wet areas • These items should be washed in companies licensed with the EPA will Toilets, sinks, washbasins, baths, shower detergent and warm water, rinsed and collect all clinical and pharmaceutical cubicles, all fittings attached to showers, stored dry between uses. Mops with waste for disposal in specialised waste baths and hand basins and surrounding detachable heads should be laundered disposal facilities which are also licensed floor and wall areas should be cleaned at between uses. by the EPA. least daily and more frequently as Spills of laboratory cultures of human Waste should be removed from clinical required. pathogens areas at least three times each day and Walls and fittings Spills of laboratory cultures should be more frequently as needed such as from Walls and screens should be cleaned absorbed on to paper towels and specialised areas. Waste bags should be quarterly or if visibly soiled. Blinds and disposed of as clinical waste. The tied before removing from the area. curtains should be cleaned quarterly or if contaminated surfaces should be treated General waste visibly soiled. Carpets should be with 2.0-2.5% sodium hypochlorite, left Place in general waste bin for removal. vacuumed daily and other floor surfaces for one hour and cleaned again with washed daily and when soiled. paper towels that are disposed of as Clinical waste clinical waste. Place in biohazard bags as soon as Bed and examination screens should be possible. Biohazard bags have a changed weekly and when visibly soiled. Laboratories should also refer to AS/NZS biohazard symbol and are currently Cleaning for Creutzfeldt-Jakob disease 2243.3:2002: Safety in laboratories - coloured yellow. infectious agents Microbiological aspects and containment facilities. Single use sharps should be placed (by Spills of central nervous system tissue or the user) into a sharps container that cerebrospinal fluid should be absorbed Waste disposal meets the Australian and New Zealand onto paper towels and disposed of by General Standards AS 4031:1992 and AS/NZS incineration. The surface should then be All health care facilities should have 4261:1994. soaked with 1 molar sodium hydroxide or policies and procedures in place for the 2.0-2.5% sodium hypochlorite, left for one Pharmaceutical waste correct management of all waste hour and cleaned again with paper towels When uncertain about how to dispose of generated. The Environmental Protection that are disposed of by incineration. leftover pharmaceuticals they should be Authority (EPA) has clear guidelines on Spills of blood or other body fluids and returned to pharmacy for correct how waste should be managed. The tissues should be cleaned using standard disposal. National Health and Medical Research spills management procedures. Personal Most disinfectants can be disposed of Council (NHMRC) also has guidelines on protective equipment used when through the sewer system by running the management of waste generated in cleaning contaminated surfaces should cold water into the sink prior to pouring health care facilities. be incinerated after use. Reusable eye the disinfectant into the sink. Leaving the protection should be cleaned as above. Waste is classified into three main cold water running for a few moments groups of waste: Maintenance of cleaning equipment after the disinfectant has been disposed • Cleaning items (including solutions, • general of as this dilutes the disinfectant. water, buckets, cleaning cloths and • clinical mop heads) should be changed after • pharmaceutical each use. They should also be changed immediately following the cleaning of All waste should be stored in secure blood or body substance spills. areas until collected. Waste disposal The blue book: Guidelines for the control of infectious diseases 261

Further information • National Health & Medical Research Council 1999, National guidelines for waste management in the health industry, http://www.nhmrc.gov.au • Environmental Protection Authority Victoria 1993, Manual for the management and disposal of biomedical wastes in Victoria (under review) • Australian/New Zealand Standards AS/NZS 3816:1998, Management of clinical and related wastes • Australian/New Zealand Standards AS 4031:1992, Non-reusable containers for the collection of sharp medical items used in health care areas • Australian/New Zealand Standards AS/NZS 4261:1994, Reusable containers for the collection of sharp items used in human and animal medical applications 262 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 263

Appendix 7: Infections in children’s services centres

Children in day care centres and other Infections with the following organisms children’s services centres and have been shown to be more common in kindergartens are particularly at risk of these settings, or have been reported as developing communicable diseases epidemic: because of: • Respiratory Syncytial virus (RSV) • Close contact with other children and • Influenza virus staff • Haemophilus influenzae type b • Lack of previous exposure to common infections • Neisseria meningitidis • Lack of toilet training • Shigella spp • Lack of control of other body • Rotavirus secretions • Giardia lamblia • Mouthing behaviour • Cryptosporidium These risk factors may be increased • Hepatitis A when staff are not appropriately trained, • E. coli group sizes are large, and mixing of age • Campylobacter spp groups occurs. • Parvovirus B19 (erythema infectiosum) • Coxsackievirus group A (hand, food and mouth disease) • Streptococcus, pyogenes, Staphylococcus aureus (impetigo) • Cytomegalovirus • Scabies • Head lice 264 The blue book: Guidelines for the control of infectious diseases The blue book: Guidelines for the control of infectious diseases 265

Appendix 8: School exclusion table

The following table indicates the minimum period of exclusion from schools and children’s service centres required for infectious diseases cases and contacts as prescribed under Regulations 13 and 14 of the Health (Infectious Diseases) Regulations 2001 – Schedule 6. In this Schedule ‘medical certificate’ means a certificate of a registered medical practitioner.

Disease or condition Exclusion of cases Exclusion of contacts

Amoebiasis (Entamoeba histolytica) Exclude until diarrhoea has ceased Not excluded

Campylobacter Exclude until diarrhoea has ceased Not excluded

Chickenpox Exclude until fully recovered or for at least 5 days after the eruption Any child with an immune deficiency first appears. Note that some remaining scabs are not a reason for (for example, leukaemia) or receiving continued exclusion chemotherapy should be excluded for their own protection. Otherwise not excluded

Conjunctivitis Exclude until discharge from eyes has ceased Not excluded

Diarrhoea Exclude until diarrhoea has ceased or until medical certificate Not excluded of recovery is produced

Diphtheria Exclude until medical certificate of recovery is received following at Exclude family/household contacts least two negative throat swabs, the first not less than 24 hours after until cleared to return by the finishing a course of antibiotics and the other 48 hours later Secretary

Haemophilus type b (Hib) Exclude until medical certificate of recovery is received Not excluded

Hand, foot and mouth disease Until all blisters have dried Not excluded

Hepatitis A Exclude until a medical certificate of recovery is received, but not Not excluded before 7 days after the onset of jaundice or illness

Herpes (‘cold sores’) Young children unable to comply with good hygiene practices should Not excluded be excluded while the lesion is weeping. Lesions to be covered by dressing, where possible

Human immuno-deficiency virus Exclusion is not necessary unless the child has a secondary infection Not excluded infection (HIV/AIDS)

Impetigo Exclude until appropriate treatment has commenced. Sores on Not excluded exposed surfaces must be covered with a watertight dressing

Influenza and influenza like illnesses Exclude until well Not excluded

Leprosy Exclude until approval to return has been given by the Secretary Not excluded

Measles Exclude until at least 4 days after the onset of rash Immunised contacts not excluded. Unimmunised contacts should be excluded until 14 days after the first day of appearance of rash in the last case. If unimmunised contacts are vaccinated within 72 hours of their first contact with the first case they may return to school

Meningitis (bacteria) Exclude until well Not excluded

Meningococcal infection Exclude until adequate carrier eradication therapy has been completed Not excluded if receiving carrier eradication therapy 266 The blue book: Guidelines for the control of infectious diseases

Disease or condition Exclusion of cases Exclusion of contacts

Mumps Exclude for 9 days or until swelling goes down (whichever is sooner) Not excluded

Poliomyelitis Exclude for at least 14 days from onset. Re-admit after receiving Not excluded medical certificate of recovery

Ringworm, scabies, Re-admit the day after appropriate treatment has commenced Not excluded pediculosis (head lice)

Rubella (german measles) Exclude until fully recovered or for at least four days after the onset Not excluded of rash

Salmonella, Shigella Exclude until diarrhoea ceases Not excluded

Severe Acute Respiratory Syndrome Exclude until medical certificate of recovery is produced Not excluded unless considered (SARS) necessary by the Secretary

Streptococcal infection Exclude until the child has received antibiotic treatment for at least Not excluded (including scarlet fever) 24 hours and the child feels well

Trachoma Re-admit the day after appropriate treatment has commenced Not excluded

Tuberculosis Exclude until receipt of a medical certificate from the treating Not excluded physician stating that the child is not considered to be infectious

Typhoid fever Exclude until approval to return has been given by the Secretary Not excluded unless considered (including paratyphoid fever) necessary by the Secretary

Verotoxin producing Exclude if required by the Secretary and only for the period Not excluded Escherichia coli (VTEC) specified by the Secretary

Whooping cough Exclude the child for 5 days after starting antibiotic treatment Exclude unimmunised household contacts aged less than 7 years and close child care contacts for 14 days after the last exposure to infection or until they have taken 5 days of a 10 day course of antibiotics

Worms (Intestinal) Exclude if diarrhoea present Not excluded

Exclusion cases and contacts is not required for Cytomegalovirus Infection, Glandualr fever (mononucleosis), Hepatitis B or C, Hookworm, Cytofalovirus Infection, Molluscum contafiosum, or , Parvovirus (erythema infectiosum, fifth disease).