PRACTICE occupational health Management of needlestick in general dental practice A. J. Smith,1 S. O. Cameron,2 J. Bagg,3 and D. Kennedy,4

The objective of this paper is to advise on the development of Glossary of abbreviations practical policies for needlestick injuries in general dental practice. BBV Blood borne virus Policies for dealing with occupational exposure to chronic blood EPP Exposure prone procedure HBV virus borne viruses, namely, hepatitis B, C and HIV are evolving. This HBs Hepatitis B surface antigen article was particularly prompted by recent changes in post HCV virus exposure prophylaxis for HIV infection. A flow chart is also included HCW Healthcare worker HIV Human immunodeficiency which should be of possible use in general dental practice. virus Needlestick injuries are of increasing concern to healthcare workers. IVDU Intravenous drug user Succesful prophylaxis requires careful planning in advance. Whilst all PEP Post exposure prophylaxis RIDDOR Reporting of Injuries, practices should have a policy for sharps injuries, prevention of Diseases and Dangerous needlestick injuries remains the best policy. Occurrences Regulations

ealthcare workers (HCW) including tice in the United Kingdom, hepatitis B from HCV RNA negative sources.12 The Hdental staff, may be exposed to blood- immunisation is mandatory,9 but there are prevalence of HCV in dental staff has var- borne viruses (BBV) carried in blood, oral few formal checks on compliance. Dental ied from 0 to 6.2%.13–17 fluids and tissues. (HBV), personnel who either have not completed a HIV prevalence is now estimated at (HCV) and human course of hepatitis B immunisation, or who 30,000 in the UK.18 The risk of HIV trans- immunodeficiency virus (HIV) are the are non-responders to the vaccine, are at mission following a single exposure to a principal blood borne pathogens of concern significant risk of infection. For such indi- contaminated sharps device has been deter- to dental staff. viduals, the possible need for prophylaxis mined from various prospective and cross- In the UK, HBV currently affects less than with hepatitis B immunoglobulin following sectional studies in HCW. Of over 6,955 0.1% of the population, although carriage a needlestick must not be overlooked. occupational exposures to sharps contami- rates are higher in risk groups, such as intra- HCV prevalence in the UK is estimated nated with HIV infected blood there were venous drug users. HBV is the most infec- at 0.5–1% in the general population. How- 22 seroconversions or 0.32%.19,20 There was tious of the three viruses with a 30% risk of ever, in risk groups, such as intravenous a lower risk from mucocutaneous exposure seroconversion following a sharps injury drug users, antibody prevalence can be up (0.03%).19,20 Many of the body fluids from involving a high risk carrier to a susceptible to 85% with approximately 60% carrying which HIV has been isolated, such as saliva, individual. HBV has frequently been trans- the virus.10 In the US, a review of pub- have not as yet been implicated in occupa- mitted in dental practice,1–4 although infec- lished studies in HCWs who received a tional transmission. Furthermore the tion rates have declined considerably in needlestick injury from an anti-HCV posi- nature of injuries sustained in dental prac- dental staff as a consequence of immunisa- tive source estimated the risk of transmis- tice tend to be of relatively low risk (Table 1). tion and improvements in infection control sion to be 1.8%.11 More recently the risk of Thus the risk of HIV infection following a practices.5 However, there is evidence in the transmission was shown to be greater if dental sharps injury is low. recent literature that there are significant the source patient were positive for HCV groups of healthcare workers worldwide RNA, with no transmission occurring First aid measures who do not receive appropriate hepatitis B There are no data on the effect of first vaccination.6–8 Within general dental prac- aid treatment in reducing the risk of BBV transmission following occupational 1 3 In brief Lecturer/Hon Sp Registrar Microbiology Professor exposure. Nevertheless we recommend • This paper highlights the management of Clinical Microbiology, Infection Research Group, that for percutaneous (needlestick/sharp- Glasgow Dental Hospital & School, 378 Sauchiehall of needlestick injuries in general dental Street, Glasgow; 2Consultant Clinical Scientist, practice by use of two case scenarios. object) injuries the wound should be Regional Virus Laboratory, Gartnavel General • All dental healthcare workers should be washed (and not scrubbed) for several min- 4 Hospital, Glasgow; Consultant Physician in aware of the risks from blood borne utes with soap and water, or a disinfectant Infectious Diseases, Infection, Tropical Medicine and Counselling Service, Brownlee Centre, Gartnavel viruses associated with sharps injuries. with known activity against BBVs (10% General Hospital, Glasgow • All practices should have a policy for iodine solution or chlorine compounds). *Correspondence to: Dr A J Smith the management of a sharps injury, Pressure above the wound to induce bleed- email: [email protected] however, prevention of injuries remains ing from the contaminated injury should REFEREED PAPER the best policy. Received 24.08.00; Accepted 04.01.01 also be performed. For a mucous mem- © British Dental Journal 2001; 190: 645–650 brane exposure we recommend copious

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Table 1 Types of injuries with high risk of HIV seroconversion

• A deep injury: transmission through the skin by a needlestick, or a puncture wound or by contamination of a cut. • Penetrating injury by a device visibly contaminated with blood. • Injury with a needle that had previously been placed directly in the source patient's artery or vein. irrigation with tap water, sterile saline or sterile water for several minutes. • Exposure to a source patient with end stage HIV infection. The rationale behind such first aid mea- sures is to reduce the bioburden below the Source: Case-control study of HIV seroconversion in healthcare threshold of an infectious dose. Therefore workers after percutaneous exposure to HIV infected blood – France, dilution with water may, of itself, lower the United Kingdom and United States, January 1988-August 1994. number of organisms below that required to Anonymous MMWR 1995: 44; 929-933. initiate infection. The application of disin- fectant solutions may further help. It is very important not to scrub the injury since this may inoculate the virus into the tissues. Health Departments.24 There are practical dental practice will now be illustrated by Downstream pressure above the wound difficulties and substantial inconvenience to means of two hypothetical case scenarios. may help to extrude infectious material. obtaining advice following a sharps expo- These procedures are of equal relevance to sure and, where necessary, HIV drug pro- Scenario 1 all blood borne viruses. phylaxis. Time is important and ideally The time is 5.00pm on a Friday afternoon, prophylaxis should commence within prior to a bank holiday weekend! Following New policies on the management of 1 hour of the incident.24,25 The biological an inferior dental block a dentist accidentally HIV associated occupational rationale for post exposure prophylaxis sticks the needle into his thumb and notices exposure (PEP) relies on the time interval required for blood accumulating under his glove. The virus uptake, processing and incorporation patient is a 28-year-old male on his second Risk assessment after initial inoculation. The hope is that visit to the practice. The first documented case of HIV sero- appropriate can prevent viral conversion following a needlestick replication. PEP does not prevent infection How should the incident be managed? occurred in 1984.21 Since then, surveil- but may prevent incorporation and immor- First stop all operative procedures. Now lance of occupationally acquired HIV talisation of viral DNA into host DNA. identify and examine the wound. Then infection has been established in several There are several lines of evidence to sup- immediately institute some basic first aid, countries. Good epidemiological data are port the use of anti-retroviral agents in PEP, namely, wash but do not scrub the injury important for accurate interpretation of such as data from animal studies26,27 as well (Fig. 1). Ideally, the risk assessment should risk analysis so that prophylaxis may be as the use of to decrease vertical now be undertaken by a second competent appropriately instituted. Occupational HIV transmission in pregnancy.28 The orig- HCW. However, this may be extremely diffi- risk of HIV infection depends on the pop- inal case control study of zidovudine pro- cult to undertake in some practices. ulation prevalence of HIV, the type of phylaxis following percutaneous injuries in The first step in the assessment process is injury and the response to an injury. HCWs showed a reduction in the rate of to assess the significance of the injury. This Injuries may be classified as a ‘definite seroconversion of up to 79%.29 Currently a has been investigated by a number of stud- case’ where HIV seroconversion has been triple combination regimen, usually ies23,29 of occupationally acquired HIV documented following a known occupa- employing zidovidine (Retrovir) with infection. Most ‘definite’ cases have fol- tional exposure.22 The second or ‘possi- lamivudine (Epivir) and indinavir (Crixi- lowed percutaneous exposure.23 Some per- ble’ category implies that investigation of van) for 4 weeks is used and is believed to be cutaneous HIV exposures are of greater risk an HIV positive healthcare worker has at least as effective. However, the use of PEP than others. Those factors identified by a revealed no identified risk factor for infec- is not without drawbacks (and criticisms). case control study29 as high risk are listed in tion other than occupational exposure.22 There are now at least 15 anti-retroviral Table 1. The injury in this particular sce- The totals of ‘definite’ and ‘possible’ occu- drugs available, but all have side effects. Par- nario is not high risk because the local pationally acquired HIV infections have ticular problems include nausea, vomiting, anaesthetic needle was not placed directly amounted to 319 cases worldwide.23 anaemia, fatigue, insomnia and renal stone into the source patient’s artery or vein. These have comprised 102 definite (5 in formation.24 Concerns about anti-viral The next phase of assessment now deter- UK) and 217 possible (8 in UK). There drug resistance and drug over use thereby mines the risk posed by the patient. This have been no definite but 9 possible encouraging viral resistance are real.30 involves asking some highly personal and cases of HIV occupational transmission in Furthermore if the virus has already under- embarrassing questions (Table 2). Again dental HCWs.23 gone integration into the host genome the this is best performed by a HCW not use of anti-retrovirals is then too late to be directly involved in the incident. Great tact Chemoprophylaxis effective. is required. It may help to explain to the Guidelines on HIV post-exposure prophy- Many of these issues surrounding the patient that there is no risk to her/him but laxis have recently been updated by the UK management of sharps injuries in general there is a health concern for the injured

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HCW. The questions of a highly personal commence combination anti-retroviral but the consequences may be serious and nature can be put in context by explaining treatment prior to the result of a HIV test. the circumstances are usually stressful. that the Blood Transfusion Service routinely Chemoprophylaxis should be recom- Practitioners who are at particularly high asks them of all blood donors. This may mended to exposed HCWs after a high risk risk of HIV exposure because of their defuse any resentment. incident. For exposures with a lower, but patient groups should be encouraged to The injured practitioner should now non-negligible risk, PEP may be offered (as consider in advance, their feelings around seek expert advice.25 A telephone number in this case), balancing the risks of trans- the issue of drug prophylaxis. for sources of advice should be provided mission with those of drug efficacy and by the regional health board and usually toxicity. However, the risk in this case is of a Work practices during the follow-up period includes the local accident and emergency lower order because, although the patient About 95% of BBV infections will be department. It is helpful if your most may have high risk factors, the nature of detectable by the sixth month after exposure. recent hepatitis B antibody titre is avail- the injury was low risk. The needle had a Later, seroconversion is rare. Whilst awaiting able to quote. narrow lumen, it had not been placed serological follow up (retested at 6 weeks, All source patients should be asked if they directly into a vein or artery and there was 3 months and 6 months) a HCW need not are willing to provide a sample of blood to no visible contamination of the needle by avoid performing exposure prone proce- test for BBVs, since a positive or negative the patient’s blood. For exposures with dures (EPP), that is, procedures where there result will determine the management of the negligible risk, PEP is not justified. It must is a risk that injury to the worker may result dental HCWs injury, potentially over a be stressed that the initiation of PEP in the exposure of the patient’s open tissues period of 6 months. The appropriate person should be the responsibility of an expert in to the blood of the worker.25 This is because contacted for advice should take the blood HIV disease and be based upon details pro- the combined risk of the HCW becoming sample. Undue pressure must not be vided by the HCW about the type of injury occupationally infected and then transmit- applied to the patient to comply with this and nature of the source patient. ting to a patient during an EPP is too small to request. The result of the discussion should There is an obvious logistical problem for merit such a restriction. However, advice be recorded in the patient’s notes. the individual dental practitioner in should be given about the advisability of safe attempting to obtain this treatment after a sex and the avoidance of blood donation dur- When approached this patient fully significant exposure. This emphasises the ing the follow up period. In the unlikely event co-operated and denied engaging in need both for proper planning and for iden- of seroconversion by the HCW to established any high risk behaviour. tification of sources of expert advice prior to HIV infection, the performance of EPPs Provided the HCW’s hepatitis B antibody occurrence of an accident. The risk of trans- (including dentistry) must then cease in titre is satisfactory (ie anti-HBs antibody mission of HIV by dental needlesticks is low, accordance with recommendations.25 titre of >100 iu/l or 10–99 iu/l if last vac- cine dose was within 2 years) and arrange- ments for venepuncture of the HCW and Table 2 A list of questions to establish whether a patient is in a the patient has been made, then no further high risk category for infection with a blood borne virus action is necessary at this point. However, it is a legal requirement to log the incident in the practice accident book. Further- 1. Have you ever been told that you are positive for HIV/AID more the reporting of injuries and other hepatitis B/C infection ? occupational exposure under the Report- 2. If you are a man: have you ever had sex, even safe sex, wit ing of Injuries, Diseases and Dangerous another man? Occurrences Regulations (RIDDOR) 1995 should also be undertaken.25 The practice 3. Have you ever injected yourself with drugs? This includes dental team should discuss the incident body building drugs? and the means to reduce the risks of any 4. Have you ever lived in or visited Africa or any Far Eastern repeat incident occurring should be country and had sex with men or women living there or implemented. received hospital treatment? Would management differ if the patient 5. Have you ever received a blood transfusion outside declared that he belonged to one of the high the UK? If yes where? risk groups highlighted in Table 2? 6. Have you been a prostitute at any time? When the source patient is of unknown HIV status but is considered to have high 7. Have you ever had sex with a person in the above groups? risk factors, it is generally appropriate to

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Sharps Injury

STOP ALL PROCEDURES

Injury assessment How deep is injury ? Is device contaminated with blood ? Has needle been in patient's blood vessel ? Is the wound bleeding ?

WASH WITH WATER DO NOT DO NOT suck the area DO encourage bleeding of accidental puncture wounds by gentle squeezing above wound to increase venous back pressure. DO with warm water or saline. DO NOT swallow water used for rinsing the mouth .

Assess patients risk factors Has the patient ever had ; HIV, HBV or HCV infection ? Male to Male sex ? Injected drugs ? Lived in Africa/Far East and had sex or blood transfusion ? Sex with prostitutes or persons in the above groups ?

Identify staff immune status for HBV

Protected Incomplete protection Unprotected Antibody titre > 100 IU/L Antibody titre 10–99 IU/L if last dose No history of immunisation with HBV Antibody titre 10–99 IU/L > 2 years vaccine (if last dose < 2 years) No antibody check after full primary Failure to reach >10 IU/L antibody titre course Incomplete primary course of HBV Results unavailable after full primary Action: course Booster dose of HBV Action: Give HBIG Booster dose of HBV Follow up Follow up

s: (To be completed by each practice) A&E Dept.:……………, Occupational Health: ……………, Medical Practitioner:…………………...

Type of injury:…………………………………………….. Source patient risk assessment:………………. Your hepatitis B serostatus:……………………………. Arrangements for sampling of baseline bloods (HCW and possibly patient) should also be determined.

Fig. 1 First aid management of sharps injury

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Table 3 Suggested components for a practice sharps injury protocol

• Staff training • First aid procedures • A definition of ‘significant exposure’ • A means of assessing the risk status of the patient • Source of emergency advice and subsequent support for the Scenario 2 psychological consequences of the incident. Your new dental nurse, whilst cleaning instru- • Out-of-hours access ments prior to autoclaving, cuts her finger on • Sites of starter packs of PEP drugs and/or hepatitis B a periodontal scaling instrument. How would prophylaxis you manage this accident? • Procedure following a sharps injury • Arrangements for practice review after any exposure incident. Identify the wound and institute some basic • Arrangements for follow-up visits, follow-up testing, record first aid (Fig. 1). Next assess the significance keeping and confidentiality of the injury. Although the practitioner should be in a position to assess the imme- (Note much of this information should be available in the form of local policy diate incident, the necessity to obtain base- documents issued by Regional Health Boards) line blood samples means that expert advice should also be sought at this stage as out- lined in Scenario 1. During the risk assessment of this inci- cussed between the dental nurse and expert every possible scenario involving a sharps dent, your nurse informs you that she has advisor. It is unlikely that PEP would nor- injury since so much depends on the type of only just started her hepatitis B immunisa- mally be recommended in this instance, injury and the source patient. It is important tion course. There are now two actions that although the nurse’s view is very pertinent. that a seamless procedure should develop should be followed. First the dental nurse Decisions about PEP during pregnancy are from immediate first aid, through post expo- should receive a rapid course of active vacci- particularly difficult and should take sure prophylaxis (for HBV and HIV infection) nation over the next 2 months. Second, account of the balance of the risks to the to arrangements for follow-up visits, follow- hepatitis B immunoglobulin should be mother and her baby. It should not be with- up testing and confidential record keeping. given within 48 hours. held where the risks of HIV infection are Medical supervision is best undertaken by an thought to be significant. occupational health physician or, failing After the initial first aid, you suddenly remem- which, a local general medical practitioner. It ber that the scaler may have been used on an Work practices for HCWs infected with HCV is also important to remember that the oral intra-venous drug user (IVDU). Reviewing To date there have been three reported cavity contains a diverse bacterial flora, which the patient’s medical history reveals that he is instances of HCW to patient transmission may act as a source of opportunistic pathogens hepatitis C antibody positive. What do you do of HCV,31–33 none of which were in den- to cause severe wound infections. Hence it is next? tistry, suggesting that the risk of transmis- important that wounds are also treated appro- Hepatitis C virus (HCV) is found in saliva sion from HCW to patient is low. Based on priately for potential bacterial infections. The but is most frequently acquired by direct this evidence, the UK Advisory Group on efficacy of personal protective equipment, blood to blood contact. The estimated risk Hepatitis are recommending that HCWs especially gloves, in preventing exposure has of transmission after needlesticks is 1.8%.11 with hepatitis C infection are not prevented frequently been questioned. Studies of the The commonest mode of transmission in from performing EPPs unless they have effect of latex gloves upon the volume of blood the UK is the sharing of blood contami- already been shown to transmit hepatitis C, inoculated during needlestick injury have nated injecting equipment by IVDUs.10 but this advice is kept under constant shown a significant benefit, reducing the vol- Both sexual and perinatal transmission can review. However, a HCW with HCV infec- ume of transferred blood by 46-86%.34 occur but in general these are less efficient tion should obtain advice from an occupa- The best policy of all is to prevent sharps modes of transmission. No prophylactic tional health unit to optimise precautions to injuries. Thus all dental practices should measures involving drugs or immunoglob- reduce the potential risk of transmission have a written, relevant, up-to-date and eas- ulin are presently available so first aid man- during EPPs. Advice should also be obtained ily accessible protocol that is understood by agement is very important. It is also about local arrangements for the reporting, all practice personnel. Suggestions for such a essential that a baseline blood sample be assessment and management of any incident practice protocol are illustrated in Table 3. taken at the time of the injury. If an exposed in which patients appear to have been The most important aspect of the preven- staff member subsequently seroconverts exposed to blood of an infected HCW. tion and management of sharps injuries is to then referral for specialist monitoring of undertake staff training. Regular staff train- liver function and assessment for antiviral Development of a sharps/needlestick ing should focus on topics such as the avoid- therapies is recommended. incident protocol ance of injuries, the use of heavy duty gloves The patient is also in a high risk category So far, data have indicated that the risk of and of eye protection whilst cleaning instru- for HIV infection, although the injury con- blood borne viral infections acquired in the ments or, preferably, use of ultrasonic clean- stitutes a low risk incident. However, the dental environment is reassuringly low. How- ers with suitable detergents, and the option of HIV prophylaxis should be dis- ever, it is difficult to be prescriptive about immediate application of first aid treatment.

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This may require modification of current 6 Gyawali P, Rice P S, Tilzey A J. Exposure to Study Group on Occupational Risk of HIV procedures and working practices. It is also blood borne viruses and the hepatitis B infection. The risk of occupational human vaccination status among healthcare workers in immunodeficiency virus infection in health useful to explore what action should be inner London. Occup Environ Med 1998; 55: care workers. Archs Intern Med 1993; 153: taken following possible exposure and 570-572. 1451-1458. indeed to undertake role-play in the proper 7 Thompson S C, Norris M. Hepatitis B 21 Anon. Needlestick transmission of HTLV-III vaccination of personnel employed in from a patient infected in Africa. Lancet 1984; first aid response to an injury. An HCW who Victorian hospitals: are those at risk adequately ii: 1376-1377. is particularly at risk should be encouraged protected? Infect Control Hosp Epidemiol 1999; 22 Evans B. Occupational acquisition of HIV to consider in advance their attitudes to PEP, 20: 51-54. infection among health care workers in the should an incident occur. It is also important 8 Tatham D, Holden J. Hepatitis B vaccination United Kingdom: data to June 1997. Comm Dis for occupational risk: an audit in general Pub Health 1998; 1: 103-107. to report all work-related injuries. practice. Community Dis Pub Health 1999; 2: 23 Public Health Laboratory Service AIDS & STD 219-221. Centre and Collaborators. Occupational Conclusion 9 Department of Health. Protecting Health Care transmission of HIV. Summary of published Workers and Patients from Hepatitis B: reports. Dec 1999 ed. The risk of occupationally related blood Recommendations of the Advisory Group on 24 Expert Advisory Group on AIDS HIV. Post- borne viral infection from patient to dentist Hepatitis. Department of Health, HSG(93)40, exposure prophylaxis: guidance from the UK or vice versa is exceptionally low. The intro- 1993. Addendum issued under cover of Chief Medical Officers’ Expert Advisory Group duction of universal precautions and EL(96)77, 1996. on Aids. London: Department of Health, 2000. 10 Ramsay M E, Balogun M A, Collins M, Balraj 25 UK Health Department. Guidance for clinical hepatitis B immunisation by the dental V. Laboratory surveillance of hepatitis C virus health care workers: protection against infection profession has done much to reduce the infection in England and Wales: 1992 to 1996. with blood borne viruses. Recommendations of risks of such occupational infections. The Comm Dis and Pub Health 1998; 1: 89-94. the Expert Advisory Group on AIDS and the implications of new anti-viral treatments 11 CDC. Recommendations for follow-up of Advisory Group on Hepatitis. 3rd edition. HCW after occupational exposure to hepatitis London: Department of Health 1998. and diagnostic techniques continue to C virus. MMWR Morb Mortal Wkly Rpt 1997; 26 Black R J. Animal studies of prophylaxis. Am J unfold. It is important to keep abreast of 46: 603-606. Med 1997; 102: 39-44. these changes since they may impact on 12 Dore G J, Kaldor J M, McCaughan G W. 27 Böttiger A, Johansson N G, Samuelsson B et al. Systematic review of role of polymerase chain Prevention of simian immunodeficiency virus, dental practice. However, despite this a sit- reaction in defining infectiousness among SIVsm or HIV-2 infection in cynomolgus uation may arise where a considerable people infected with hepatitis C virus. BMJ monkeys by pre and post-exposure degree of doubt exists about the most 1997; 315: 333-337. administration of BEA-005. AIDS 1997; 11: appropriate action to take, especially in the 13 Herbert A M, Walker C M, Davies K J et al. 157-162. Occupationally acquired hepatitis C virus 28 Connor E M, Sperling R S, Gerber R et al. setting of general dental practice where infection. Lancet 1992; 339: 305. Reduction of maternal-infant transmission of expert advice may be particularly difficult 14 Gerberding J L. Incidence and prevalence of human immunodeficiency virus type 1 with to obtain. Written protocols should there- human immunodeficiency virus, hepatitis B zidovudine treatment. N Engl J Med 1994; 331: virus, hepatitis C virus and cytomegalovirus 1173-1180. fore be readily accessible within the practice among health care personnel at risk for blood 29 Case-control study of HIV seroconversion in to deal with such an eventuality. Finally, few exposure: final report from a longitudinal health-care workers after percutaneous other situations exist where the maxim that study. J Infect Dis 1994; 170: 1410-1417. exposures to HIV-infected blood: France, ‘prevention is better than cure’ applies 15 Lodi G, Porter S R, Teo C G, Scully C. United Kingdom and United States; January Prevalence of HCV infection in health care 1988-August 1994. MMWR 1995; 44: 929-933. more pertinently than that of needlestick workers of a UK dental hospital. Br Dent J 30 Jochimsen E M. Failures of zidovudine injuries. Regular staff training will do much 1997; 183: 329-332. postexposure prophylaxis in human to reduce the physical and psychological 16 Thomas D L, Factor S H, Kelen J D et al. Viral immunodeficiency virus post-exposure consequences of such an incident. hepatitis in health care personnel at the John management of health care workers. Am J Med Hopkins Hospital. Archs Int Med 1993; 153: 1997; 102: 2-5. 1705-1712. 31 CDSC. Hepatitis C virus transmission from 1 Scheutz F, Mellbye M, Esteban J I et al. 17 Thomas D L, Gruninger S E, Siew C et al. health care worker to patient. Comm Dis Rep Hepatitis B virus infection in Danish dentists; Occupational risk of hepatitis C infections CDR Wkly 1995; 5: 121. a case control study and follow-up study. Am J among general dentists and oral surgeons in 32 Esteban J I, Gomez J, Martell M et al. Epidemiol 1988; 128: 190-196. North America. Am J Med 1996; 100: 41-45. Transmission of hepatitis C virus by a cardiac 2 Porter S R, Scully C. HIV; the surgeons 18 PHLS AIDS and STD Centre – Communicable surgeon. N Engl J Med 1996; 334: 555-560. perspective. Br J Oral Max Surg 1994; 32: Disease Surveillance Centre and Scottish Centre 33 Duckworth G J, Heptonstall J, Aitken C. For 222-230. for Infection & Environmental Health. the Incident Control Team and others: 3 Cottone J A, Puttaiah R. Hepatitis B virus AIDS/HIV Quarterly Surveillance tables No. transmission of hepatitis C from a surgeon to a infection. Dent Clin North Am 1996; 40: 46: 00/1 May 2000. patient. Commun Dis Public Health 1999; 2: 293-307. 19 Tokars J I, Marcus R, Culver D H et al. 188-192. 4 Schiff E R, de Medina M D, Kline S N et al. Surveillance of HIV infection and zidovudine 34 Mast S T, Woolwine J D, Gerberding J L. Veterans administration cooperative study on use among health care workers after Efficacy of gloves in reducing blood volumes hepatitis and dentistry. J Am Dent Assoc 1986; occupational exposure to HIV infected blood: transferred during simulated needlestick 113: 390-396. the CDC Cooperative Needlestick Surveillance injury. J Infect Dis 1993; 168: 1589-1592. 5 Polakoff S. Acute viral hepatitis B; laboratory Group. Ann Intern Med 1993; 118: 913-919. reports 1985-8. Comm Dis Report 1989; 26-29. 20 Ippolito G, Puro V, De Carli G and the Italian

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