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87 PLAGUE Causative Agent Yersinia Pestis Incubation Period 2-6 Days

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87 PLAGUE Causative Agent Yersinia Pestis Incubation Period 2-6 Days PLAGUE Causative Agent PLAGUE Yersinia pestis Causative Agent IncubationYersinia pestis Period 2 -6 days Incubation Period Infectious2-6 days Period Throughout duration of illness (pneumonic plague is the most important infectious form).Infectious Period Throughout duration of illness (pneumonic plague is the most important infectious Tform).ransmission Transmitted from rats by flea bites, by handling infected animal tissues, or airborne Tbyransmission aerosol from animals or humans with pneumonic plague. Transmitted from rats by flea bites, by handling infected animal tissues, or airborne Epidemiologyby aerosol from animals or humans with pneumonic plague. There are natural foci of plague infection of rodents in many parts of the world. WildEpidemiology rodent plague is present in central, eastern and southern Africa, South AmeThererica, are thenatural western foci partof plague of North infection America of rodentsand in largein many areas parts of Asia.of the In world. some areas,Wild contactrodent betweenplague iswild present and domestic in central, rats iseastern common, and resulting southern in sporadicAfrica, Southcases ofAme humanrica, plaguethe western and occasional part of North outbreaks. America and in large areas of Asia. In some areas, contact between wild and domestic rats is common, resulting in sporadic cases ofIn humanSoutheast plague Asia, and Myanmar occasional and outbreaks.Vietnam report the highest number of cases. ClinicalIn Southeast Features Asia, Myanmar and Vietnam report the highest number of cases. Plague should be suspected in anyone with fever and painful lymphadenopathy who hasClinical been Featuresto an endemic country. Plague should be suspected in anyone with fever and painful lymphadenopathy who Therehas been are to three an endemic principal country. clinical presentations: Bubonic plague: initial fever, headache, myalgia followed by painful acute Thereregional are three lymphadenopathy principal clinical presentations:(pathognomonic bubo), typically involving the inguinal,Bubonic plagueaxillary: initialor cervical fever, regions.headache, If leftmyalgia untreated, followed rapid by progressionpainful acute to septiregionalcaemia lymphadenopathy and secondary plague (pathognomonic pneumonia occursbubo), (fatality typically 50 - involving60%). the inguinal,Septicaemic axillary plague or: occurscervical when regions. Y. pestis If left invades untreated, the bloodstream.rapid progression It can to septifollowca ebubonicmia and plaguesecondary or occurs plague without pneumonia detectable occurs lymphadenopathy(fatality 50 - 60%). (primary septicaemicSepticaemic plagueplague).: occurs Complications when Y. pestisinclude invades septic the shock,bloodstream. disseminated It can fointravascularllow bubonic coagulation, plague or occursmeningitis without and multiorgandetectable lymphadenopathyfailure. (primary Pneumonicsepticaemic plague:plague). the leastComplications common but incl theude most septic dangerous shock, and disseminatedfatal form of theintravascular disease. Itcoagulation, can develop meningitis as a complication and multiorgan of failure.septicaemic plague or be Pneumonicacquired dire plague:ctly by the inhalation least common of aerosols but the mostfrom dangerous a human andor fatalanimal form with of thepne udisease.monic plague. It can Thedevelop signs as include a complication severe pneumonia, of septicaemic fever, dyspnoeaplague or andbe acquired directly by inhalation of aerosols from a human or animal with pneumonic plague. The signs include severe pneumonia, fever, dyspnoea and 87 87 often haemoptysis. Patients who do not receive treatment within 18 hours of onset of respiratory symptoms are unlikely to survive. often haemoptysis. Patients who do not receive treatment within 18 hours of Investigationsonset of respiratory symptoms are unlikely to survive. Blood, bubo aspirate, sputum/throat swab, necropsy material can be sent for Investigationsisolation of Y. pestis. AcuteBlood, and bubo convalescent aspirate, sputum/throat serology for fourfoldswab, necropsy rise in titre. material A single can titre be >1:16sent for is suggestive.isolation of Y. pestis. AcuteInform and the convalescentlaboratory beforehand serology forso fourfoldthat arrangements rise in titre. can A besingle made titre to >1:16forward is suggestive.samples if necessary to the Department of Pathology, Singapore General InformHospital, the or laboratory other designated beforehand sites. so that arrangements can be made to forward samples if necessary to the Department of Pathology, Singapore General NotificationHospital, or other designated sites. A legally notifiable disease in Singapore. Notify Ministry of Health (Form MD 131 Notificationor electronically via CD-LENS) not later than 24 hours from the time of diagnosis. ACall legally MOH notifiable Communicable disease Diseasesin Singapore. Surveillance Notify Ministry team at: of 98171463Health (Form immediately MD 131 oron electronsuspicion.ically via CD-LENS) not later than 24 hours from the time of diagnosis. Call MOH Communicable Diseases Surveillance team at: 98171463 immediately Managementon suspicion. All cases must be managed at the Communicable Disease Centre (CDC). Management AllGentamicin, cases must st reptomycin,be managed atchloramphenicol the Communicable or tetracyclineDisease Centre are (CDC).highly effective if used within hours of presentation. Gentamicin, streptomycin, chloramphenicol or tetracycline are highly effective if Infectionused within Control hours of presentation. Patients with uncomplicated infection who are promptly treated present no Infectionhealth Control hazard to others. PatientsThose with with cough uncomplicated and other infectionsigns of whopneumonia are promptly must betreated placed present in strict no healthrespira hazardtory isolation to others. for at least 48 hours after the institution of antibiotic Thosetherapy withor until cough the sputumand other culture signs is negative.of pneumonia must be placed in strict respirBubo aaspiratetory isolation and blood for atmust least be 48handled hours withafter glovesthe institution and aerosolization of antibiotic of therapythese materials or until shouldthe sputum be avoided. culture is negative. BuboLaboratory aspirate workers and bloodmust bemust alerted be handled to exercise with precautionsgloves and althoughaerosolization standard of thesebacteriological materials techniquesshould be avoided. that safeguard against skin contact and aerosolization Laboratoryshould be adequate. workers must be alerted to exercise precautions although standard bacteriological techniques that safeguard against skin contact and aerosolization Preventionshould beand adequate. Control All cases will be isolated at CDC, Tan Tock Seng Hospital. Prevention Case investigations and Control will be carried out and contact tracing will be intensified. InAll the cases event will of be death, isolated proper at CDC, disposal Tan of Tock the body Seng is Hospital. important. CasesCase investigations and close contacts, will be including carried out their and clothing contact andtracing personal will be belongings, intensified. will beIn thedisinfected event of withdeath, insecticide proper disposal dusting. of the body is important. Cases and close contacts, including their clothing and personal belongings, will be disinfected with insecticide dusting. 88 88 Anti-flea measures and rodent trapping will be increased at the focus of transmission. TheAnti -publicflea measures and the World and rodentHealth Organisationtrapping will will be beincreased informed at of theall suspectedfocus of andtran sconfirmedmission. cases. The public andwill thebe Worldadvised Health to step Organisation up measures will to preventbe informed rodent of infestationall suspected in theand premisesconfirmed and cases. to avoid contact with rodents (either live or dead). The public will be advised to step up measures to prevent rodent infestation in Chemoprophylaxisthe premises and to avoid contact with rodents (either live or dead). Consider antibiotic prophylaxis for the following: Chemoprophylaxis. Persons exposed to patients with pneumonic plague. Consider. Persons antibiotic exposed prophylaxis to bites forof thewild following: rodent fleas during an outbreak or to . tiPersonsssues/fluids exposed of a to plague patients-infected with pneumonic animal. plague. Persons travellingexposed toto highlybites endemicof wild arearodent for shortfleas duration.during an outbreak or to tissues/fluids of a plague-infected animal. For. Personsadults, travellingdoxycycline to highly is the endemic best choicearea for (100mgshort duration. orally bd for 7 days). Trimethoprim -sulfamethoxazole is a suitable alternative. For adults, doxycycline is the best choice (100mg orally bd for 7 days). IndicationsTrimethoprim for-sulfameth vaccine oxazoleusage is a suitable alternative. A formalin-killed plague vaccine has been used for the following groups: Indications Travellers for to vaccine endemic usage or hyperendemic areas. A formalinIndividuals-killed who plague must vaccine live and has work been in used close for contact the following with rodents. groups: LaboraTravellerstory to workers endemic who or hyperendemicmust handle live areas. cultures of Y. pestis. MilitaryIndividuals personnel who must deployed live and in workplague in- endemicclose contact areas. with rodents. Laboratory workers who must handle live cultures of Y. pestis. This Militaryvaccine ispersonnel not routinely
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