Human immunodeficiency virus postexposure prophylaxis for occupational exposure in a medical school hospital in Thailand

This is a retrospective review of occupational exposure to human immunodeficiency virus (HIV) and subsequent postexposure prophylaxis (PEP) among healthcare workers (HCWs) in King Chulalongkorn Memorial Hospital (KCMH), Bangkok, Thailand. From January 2002 to December 2004, data were collected from incident reports, the hospital's infectious diseases unit and the emergency department. There were 315 reported episodes of occupational exposure among 306 HCWs. Nurses (34.0%) were the HCWs most frequently exposed and percutaneous injury (91.4%) was the most common type of exposure. One-third of the source patients tested were infected with HIV. PEP was initiated following 200 (63.5%) of the 315 exposures and was started within 24h in >95% of cases. The most commonly prescribed PEP regimen was zidovudine, lamivudine and nelfinavir. Fifty-six percent of HCWs given PEP completed a four-week course but the remainder discontinued PEP prematurely due to side-effects, or after negative results from the source, or following informed risk reassessment or from their own accord. No exposed HCW acquired HIV during the study period. Appropriate counselling and careful risk assessment are important in achieving effective HIV PEP among HCWs.     

Exposure of health care workers to pentamidine isethionate.

Pentamidine isethionate is currently used for the prophylaxis and treatment of Pneumocystis carinii pneumonia. Its use has been associated with a number of symptoms in staff administering treatment, and there are some additional concerns about possible adverse health effects of long term exposure. The aim of this study was to quantify exposure of health care staff administering nebulized pentamidine to patients. Personal breathing zone and static air samples at the height of the patient's head were collected during the nebulization of pentamidine to nine sequential outpatients attending a haemophilia unit. These were analysed using a standard method allowing the exposure of staff to be estimated. The duration of treatment varied between 15 and 60 min. Personal breathing zone samples showed exposure to be between 2 and 100 micrograms/m3. Static samples showed the concentration of pentamidine in the room varied from 15 to 2,100 micrograms/m3. While these exposures were relatively low, they were higher than some other studies have reported, and may pose some risk of adverse effects to staff. Some simple measures could reduce staff exposure.     

Occupational exposure to HIV and the use of post-exposure prophylaxis

The use of antiretroviral therapy as post-exposure prophylaxis against human immunodeficiency virus (HIV) is now routine following high-risk exposure to the HIV virus. This article summarizes the management of health care workers and others exposed to HIV in an occupational setting, and the evidence behind it.     

Occupational transmission of HIV in health care workers: A review

Health care workers have a small but real risk of acquiringHIV infection as a result of occupational exposure. In thispaper, we review all reports in the scientific literature from1984 through to December 1993 of confirmed and probable casesof HIV seroconversion after a specific occupational exposure.A total of 64 confirmed cases have been reported, 24 in Europe,36 in the USA and 4 in other countries. Most seroconversionshave resulted from percutaneous exposure (91%) to AIDS patients(62%), usually caused by hollow bore needlestick injuries inflictedduring blood drawing procedures. Almost all seroconversionshave been detected within 6 months of exposure (94%) and haveusually been preceded by an episode of acute illness (73%).Ten seroconversions have occurred in spite of partial or completecourses of zidovudine prophylaxis. An additional 113 probablecases have been reported, 75 in the USA, 35 in Europe and 3in other countries. Aggregating the results of the prospectivestudies carried out, it is calculated that the risk of seroconversionfollowing percutaneous exposure is 0.33% or 3 in 1000 exposures(95% Cl: 0.21–0.52%), while the risk following mucocutaneousexposure is much lower (0.04%, 95% Cl: 0.006–0.31%). Thedocumented failure of zidovudine prophylaxis following occupationalexposure in a number of instances indicate its effect is, atbest, only partial; furthermore, exposure to source patientswho have been receiving the drug may lead to transmission ofzidovudine-resistant strains of HIV. Risk factors for occupationalexposure to HIV and for transmission, given that an exposurehas occurred, are discussed.     

Effect of zidovudine postexposure prophylaxis on the development of HIV-specific cytotoxic T-lymphocyte responses in HIV-exposed healthcare workers.

We evaluated the effects of zidovudine postexposure prophylaxis (PEP) on the development of human immunodeficiency virus (HIV) envelope-specific cytotoxic T-lymphocyte responses in 20 healthcare workers with occupational exposures to HIV. Seven healthcare workers were treated with zidovudine PEP. Only 1 of 7 treated, versus 6 of 13 not treated, developed an HIV envelope-specific cytotoxic T-lymphocyte response. These data suggest that zidovudine abrogated HIV-specific cytotoxic T-lymphocyte responses. HIV-specific cytotoxic T-lymphocyte responses may be useful as a surrogate marker of HIV replication in the evaluation of new regimens for PEP of occupational HIV exposures.     

Risk for occupational transmission of HIV infection among health care workers

The aim of this study was to evaluate the HIV seroconversion rate associated with different types of occupational exposures in health care workers. A longitudinal study was conducted from January 1986 to October 1992 in a teaching hospital in Spain, where HIV infection is prevalent among patients. Each health care worker was asked to complete a questionnaire regarding age, sex, staff category, lace of exposure, other exposures, type of exposure, body fluid, infected material and HIV status of source patient. These health care workers were then followed up at 6 weeks, 3 months, 6 months and 12 months with repeated test for HIV antibody. Four hundred twenty three reports of occupational exposure were analysed. Nursing was the profession with more exposures (42.8%). Ninety five percent of total exposures were percutaneous, 4% mucous membrane contacts and 1% skin contacts, 88.3% were described as blood contact and 71.8% had resulted from needlestick and suture needles. Exposures from HIV-positive patients comprised 23.2% of occupational exposures. There was a significant difference in the length of follow-up in physicians (p=0.00009) and nurses (p=0.00001), when we compared HIV-positive patients with patients in whom the HIV status was unknown or negative. The HIV seroconversion rate was 0.00%. We consider that the risk of acquiring HIV infection via contact with a patient is low, but not zero. Well documented cases of seroconversion have been published. Because it is often impossible to know a patient's infection status, health care workers should follow for rotine the universal precautions for all patients when there is a possibility of exposure to blood or other body fluid. Equally important is the development of new techniques to minimize the risk of exposures to blood.     

Occupational asthma in New South Wales (NSW): a population-based study

BACKGROUND: The proportion of asthma in adults that is due to occupational exposures is not known. AIM: To examine the contribution of workplace exposures to the development of asthma in adults in New South Wales (NSW) in a cross sectional, population-based study. METHODS: A randomly selected population of 5,331 18- to 49-year olds completed and returned a mailed questionnaire (response rate 37%). In adult-onset asthmatics we examined the association of asthma with reported exposure, within 1 year of asthma onset, to a list of occupations and exposures known to be at risk for occupational asthma (high-risk jobs and exposures). RESULTS: Among 910 subjects (18%) with asthma, 383 (7%) subjects reported adult-onset disease. After adjusting for sex, age and smoking, working in any high-risk job or exposure at the time of asthma onset was significantly associated with adult-onset asthma (OR 1.51, 95% CI 1.19-1.92). The population attributable risk (PAR) of adult-onset asthma for either a high-risk job or an exposure was 9.5%. Sudden onset, irritant or reactive airways dysfunction syndrome type exposures were associated with adult-onset asthma (OR 4.65, 95% CI 1.64-13.2). The PAR of adult-onset asthma for these exposures was 0.2%. CONCLUSION: Reported adult onset of asthma is common and occupational exposures may be associated with 9.5% of prevalent cases of adult-onset asthma in NSW.     

Occupational exposures to metals, solvents and pesticides: recent evidence on male reproductive effects and biological markers

This review is based primarily on the recent epidemiological studies conducted in occupational settings in order to explore the relationship between exposures to chemical agents and the possible effects on male reproductive function. The paper examines evidence of the effects of metals, solvents, pesticides and dioxin. The effects considered are primarily the possible alterations of sperm quality and reduction of fertility. Many studies have identified small groups of workers with exposures to these agents, presenting some alteration in the spermatological or fertility profile, but the results are difficult to replicate in other settings with different individuals and different levels of exposure. From examination of the concentrations of environmental and occupational pollutants in the blood and in the seminal fluid of exposed individuals, it appears that, in general, the concentrations are much lower in the seminal fluid and in sperm cells, making this a less useful marker of exposure.     

Cost-effectiveness of a post-exposure HIV chemoprophylaxis program for blood exposures in health care workers.

We performed a cost-effectiveness analysis of a post-exposure chemoprophylaxis program for health care workers who sustained exposures to blood. We analyzed a program of (1) treatment with zidovudine alone versus no treatment and (2) treatment with three-drug therapy versus no treatment. Assuming that 35% of exposures were to HIV-positive sources, the zidovudine regimen prevented 53 HIV seroconversions per 100,000 exposures, at a societal cost of $2.0 million per case of HIV prevented. The cost per quality-adjusted life year saved was $175,222. A three-drug chemoprophylactic therapy program (postulating 100% effectiveness and 35% source HIV positivity), prevented 66 seroconversions per 100,000 exposures, at a cost of $2.1 million per case of HIV prevented and $190,392 per quality-adjusted life year saved. Treating sources known to be HIV-positive and treating severe exposures were the most cost-effective strategies.     

Air blast circuit breaker noise and hearing loss: a multifactorial model for risk assessment

The assessment of the risk to hearing from impulse noise exposure may be a problem for the occupational physician because existing legislative and international noise exposure standards deal primarily with continuous noise, and are not valid in excess of the peak exposure limit of 200 pa (140 dB). Noise exposure in excess of this level, for example that due to firearms, is frequently perceived as harmful, but this is not necessarily the case, as impulse noise standards do, in fact, allow exposure with a maximum in the order of 6.3 kPa (170 dB). To illustrate this, a cross-sectional group of electrical transmission workers have been studied who were exposed to significant levels of impulse noise from air blast circuit breakers and firearms. Important hearing loss factors have been identified by means of a specially designed questionnaire. Using the Health & Safety Executive definition, the risk of hearing loss was determined by calculating prevalence odds ratios (ORs) for exposure to these factors. The OR for those with fewer than eight unprotected air blast circuit breaker exposures was 2.27 (95% confidence interval (CI), 1.01-5.08), whilst for those with more than eight exposures the OR was 2.10 (95% CI, 0.97-4.54). For firearm exposure, ORs of 1.61 (95% CI, 0.95-2.74) were noted in the medium exposure group and 2.05 (95% CI, 1.08-3.86) in the high exposure group. When all the factors were included in the model, the most significant factor was age. The study gives support to the impulse noise exposure criteria, confirming the borderline risk from air blast circuit breaker noise exposure and the relative safety of moderate gunfire exposure.     

Guideline 'Needlestick injuries': risk assessment and post-exposure management in practice

Guideline 'Needle stick injuries': risk assessment and post-exposure management in practice The objective of the national guideline 'Needle stick injuries' is to make the assessment of needle stick injuries more structured and uniform. The injury is classified as high risk or low risk according to the volume of blood transmitted. For high-risk injuries measures to prevent hepatitis B, hepatitis C and HIV infection have to be considered, whereas for low-risk injuries only measures to prevent hepatitis B. The need for post-exposure prophylaxis is determined by the victim's immunity to hepatitis B and the presence of hepatitis B virus, hepatitis C virus or HIV in the source person. Post-exposure prophylaxis against hepatitis B consists primarily of hepatitis B vaccination; hepatitis B immunoglobulin is added in the case of a high-risk injury with a hepatitis B positive source or a source belonging to a risk group for hepatitis B. In high-risk injuries the victim is tested for hepatitis C and HIV transmission (except in case of a seronegative source). Antiretroviral postexposure prophylaxis is advised for high-risk injuries with a HIV seropositive source or a source belonging to a risk group for HIV.     

The impact of educational interventions on primary health care workers' knowledge of occupational exposure to blood or body fluids

AIM: To assess the impact of educational interventions on primary health care workers' knowledge of management of occupational exposure to blood or body fluids. METHODS: Cluster-randomized trial of educational interventions in two National Health Service board areas in Scotland. Medical and dental practices were randomized to four groups; Group A, a control group of practices where staff received no intervention, Group B practices where staff received a flow chart regarding the management of blood and body fluid exposures, Group C received an e-mail alert containing the flow chart and Group D practices received an oral presentation of information in the flow chart. Staff knowledge was assessed on one occasion, following the educational intervention, using an anonymous postal questionnaire. RESULTS: Two hundred and fifteen medical and dental practices were approached and 114 practices participated (response rate 53%). A total of 1120 individual questionnaires were returned. Face to face training was the most effective intervention with four of five outcome measures showing better than expected knowledge. Seventy-seven percent of staff identified themselves as at risk of exposure to blood and body fluids. Twenty-one percent of staff believed they were not at risk of exposure to blood-borne viruses although potentially exposed and 16% of exposed staff had not been immunized against hepatitis B. Of the 856 'at risk' staff, 48% had not received training regarding blood-borne viruses. CONCLUSIONS: We found greater knowledge regarding management of exposures to blood and body fluids following face to face training than other educational interventions. There is a need for education of at risk primary health care workers.     

Occupational risk factors and reproductive health of women

BACKGROUND: This in-depth review summarizes and interprets the available recent epidemiologic evidence on the relationship between occupational exposures and negative reproductive outcome among women workers. METHODS: The studies examined by the review include those published in the international scientific literature since 1990, and were identified through the search of relevant data banks using selected keywords. RESULTS: From the examination of studies dealing with exposures of women to chemical agents, pesticides, physical agents, ergonomic factors and stress, it appears that at present the evidence is sufficient to warrant the maximum protection of pregnant women to several well-documented occupational risk factors. These include exposures to anaesthetic gases, antineoplastic drugs, heavy metals, solvents, heavy physical work and irregular work schedules. For other work risks, such as exposure to non-ionizing radiation and psychosocial work stress, the evidence is often suggestive but not conclusive. CONCLUSIONS: Policy makers and health professionals should advise women and employers to avoid exposure to the well-known occupational risk factors, while epidemiologic research should pursue methodological improvements and provide more insight into the magnitude of exposures responsible for detrimental effects.     

Occupational exposures to bloodborne pathogens among healthcare workers in Rio de Janeiro, Brazil

Healthcare workers (HCWs) frequently face the risk of occupational infection from bloodborne pathogens following exposure to blood and body fluids. This study describes the results of a surveillance system of occupational exposure to bloodborne pathogens among HCWs in Rio de Janeiro, Brazil, during an eight-year period. A total of 15 035 exposures reported from 537 health units were reviewed. Six circumstances comprised nearly 70% of the reported exposures: recapping needles (14%), performing surgical procedures or handling surgical equipment (14%), handling trash (13%), during disposal into sharps containers (13%), performing percutaneous venepuncture (10%) and during blood drawing (5%). Easily preventable exposures, such as incidents related to recapping needles, handling trash, and sharps left in an inappropriate place, represented 30% of the exposures reported. Post-exposure prophylaxis (PEP) for human immunodeficiency virus (HIV) was initiated for 46% of exposed HCWs. Although Brazilian guidelines indicate that PEP is usually not recommended for exposures with insignificant or very low risk of HIV infection, PEP was prescribed to a large proportion of exposed HCWs under these circumstances. The prevention of occupational exposure to bloodborne pathogens among HCWs and their safety must be considered as a public health issue. Although infection-preventative measures such as antiretroviral drugs and rapid tests are available, this study shows that there are still a high number of easily preventable exposures. The implementation of more effective prevention strategies is urgently required in this country.     

Importance of psychosocial work factors on general health outcomes in the national French SUMER survey

AIM: To examine the associations between psychosocial work factors and general health outcomes, taking into account other occupational risk factors, within the national French working population. METHODS: The study was based on a large national sample of 24 486 women and men of the French working population who filled in a self-administered questionnaire in 2003 (response rate: 96.5%). Psychosocial work exposures included psychological demands, decision latitude, social support, workplace bullying and violence from the public. The three health indicators studied were self-reported health, long sickness absence (>8 days of absence) and work injury. Adjustment was made for covariates: age, occupation, work status, working hours, time schedules, physical, ergonomic, biological and chemical exposures. Men and women were studied separately. RESULTS: Low levels of decision latitude, and of social support, and high psychological demands were found to be risk factors for poor self-reported health and long sickness absence. High demands were also found to be associated with work injury. Workplace bullying and/or violence from the public also increased the risk of poor health, long sickness absence and work injury. CONCLUSION: Psychosocial work factors were found to be strong risk factors for health outcomes; the results were unchanged after adjustment for other occupational risk factors. Preventive efforts should be intensified towards reducing these psychosocial work exposures.     

Occupational exposure to bloodborne viruses in the Amsterdam police force, 2000-2003

OBJECTIVES: To assess and evaluate the rate and outcome of occupational exposure to hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) in the Amsterdam police force. METHODS: Retrospectively, all accidents with risk for viral transmission reported to the Municipal Health Service between January 1, 2000 and December 31, 2003 were described and analyzed in 2004. RESULTS: Over a 4-year period, 112 exposures with a viral transmission risk were reported (the estimated exposure rate was 68/10,000/year). Of these exposures, 89 (79%) sources were tested, finding 4% HBV-positive, 4% HIV-positive, and 18% HCV-positive. Immunoglobulin for HBV infection was given 44 times; HIV post-exposure prophylaxis was prescribed 16 times and 13 of 16 discontinued the course within a few days because the transmission source tested HIV-negative. No seroconversions were seen in persons exposed. CONCLUSIONS: The rate of exposure is low. The majority of the sources could be traced and tested. However, a comprehensive and effective protocol is essential in minimizing the risk of occupational HBV, HCV, and HIV infection in police officers, even if HBV vaccination is provided.     

Serious adverse events attributed to nevirapine regimens for postexposure prophylaxis after HIV exposures--worldwide, 1997-2000

In September 2000, two instances of life-threatening hepatotoxicity were reported in health-care workers taking nevirapine (NVP) for postexposure prophylaxis (PEP) after occupational human immunodeficiency virus (HIV) exposure. In one case, a 43-year-old female health-care worker required liver transplantation after developing fulminant hepatitis and end-stage hepatic failure while taking NVP, zidovudine, and lamivudine as PEP following a needlestick injury (1). In the second case, a 38-year-old male physician was hospitalized with life-threatening fulminant hepatitis while taking NVP, zidovudine, and lamivudine as PEP following a mucous membrane exposure. To characterize NVP-associated PEP toxicity, CDC and the Food and Drug Administration (FDA) reviewed MedWatch reports of serious adverse events in persons taking NVP for PEP received by FDA (Figure 1). This report summarizes the results of that analysis and indicates that healthy persons taking abbreviated 4-week NVP regimens for PEP are at risk for serious adverse events. Clinicians should use recommended PEP guidelines and dosing instructions to reduce the risk for serious adverse events.     

Risk perception and attitudes towards HIV in Serbian health care workers

BACKGROUND: Health care workers (HCWs) are at risk of occupational exposure to human immunodeficiency virus (HIV). AIM: To investigate the perception of professional risk from, and the knowledge, attitudes and practice of HCWs to HIV and AIDS in Serbia. METHODS: Cross-sectional study of 1,559 Serbian HCWs using self-administered anonymous questionnaires. Chi-square testing and multiple logistic regression analysis were applied. RESULTS: Eighty-nine per cent of HCWs believed that they were at risk of acquiring HIV through occupational exposure. The perception of professional risk was higher among HCWs frequently exposed to patients' blood and body fluids (OR 7.9, 95% CI 4.4-14.5), who used additional personal protection if the HIV status of patient was known (OR 2.6, 95% CI 1.5-4.6), who had experienced sharp injuries within the last year (OR 1.9, 95% CI 1.0-3.8) or who had been tested for HIV (OR 2.1, 95% CI 1.2-3.5), and among HCWs who had treated HIV-positive patients (OR 1.7, 95% CI 1.1-2.8). The majority of respondents had deficient knowledge about modes of HIV transmission. Attitudes towards HIV-positive patients were significantly different by occupation. Seventy per cent of HCWs used appropriate protection during their daily work with patients. CONCLUSIONS: HCWs require specific educational programmes and training protocols to ensure that they are adequately protected when carrying out high quality care.     

Costs of management of occupational exposures to blood and body fluids.

OBJECTIVE: To determine the cost of management of occupational exposures to blood and body fluids. DESIGN: A convenience sample of 4 healthcare facilities provided information on the cost of management of occupational exposures that varied in type, severity, and exposure source infection status. Detailed information was collected on time spent reporting, managing, and following up the exposures; salaries (including benefits) for representative staff who sustained and who managed exposures; and costs (not charges) for laboratory testing of exposure sources and exposed healthcare personnel, as well as any postexposure prophylaxis taken by the exposed personnel. Resources used were stratified by the phase of exposure management: exposure reporting, initial management, and follow-up. Data for 31 exposure scenarios were analyzed. Costs were given in 2003 US dollars. SETTING: The 4 facilities providing data were a 600-bed public hospital, a 244-bed Veterans Affairs medical center, a 437-bed rural tertiary care hospital, and a 3,500-bed healthcare system. RESULTS: The overall range of costs to manage reported exposures was $71-$4,838. Mean total costs varied greatly by the infection status of the source patient. The overall mean cost for exposures to human immunodeficiency virus (HIV)-infected source patients (n=19, including those coinfected with hepatitis B or C virus) was $2,456 (range, $907-$4,838), whereas the overall mean cost for exposures to source patients with unknown or negative infection status (n=8) was $376 (range, $71-$860). Lastly, the overall mean cost of management of reported exposures for source patients infected with hepatitis C virus (n=4) was $650 (range, $186-$856). CONCLUSIONS: Management of occupational exposures to blood and body fluids is costly; the best way to avoid these costs is by prevention of exposures.