Hepatitis C virus: an important occupational hazard?

Infection with Hepatitis C virus (HCV) is estimated to affect 3% of the world's population and is an important cause of liver disease. It is most commonly transmitted by percutaneous exposure. Although current evidence does not suggest an increased prevalence of HCV infection among healthcare workers, transmission of infection following occupational exposure has been demonstrated. An average transmission rate of 1.8%, following percutaneous injury, has been reported. The risk of transmission is higher from patients with viraemia, as measured by a positive polymerase chain reaction for HCV RNA. After exposure to HCV, healthcare workers should be actively followed up, initially using a test to detect viral RNA. This may facilitate earlier diagnosis and treatment. Recent reports in the UK, of transmission of infection to patients from HCV infected healthcare workers, have prompted a review of the appropriateness of HCV infected individuals undertaking exposure prone procedures.     

Risks associated with occupational glass injury in bar staff with special consideration of hepatitis B infection

Since bar workers often sustain cuts from unwashed bar glasses,the aims of this study were to investigate risk of injury andto examine the sero-prevalence of markers for hepatitis B amongstbar staff. Ninety-one bar staff recruited by newspaper advertisementwere asked about injury experience and life-style risks associatedwith transmission of hepatitis B and were tested for hepatitisB surface antigen (HBsAg) and core antibody (anti-HBc). Seventy-fourper cent reported lacerations from broken glassware at work:18% had sustained such injuries in more than 10 incidents. Fifty-fiveper cent of respondents reported occupational skin contact withbody fluids. Anti-HBc prevalence for the study group was 1.1%,suggesting that bar staff were not at increased risk from hepatitisB infection. Although 30% wore gloves for high-risk tasks, therewas no evidence that glove wearing prevented glass lacerations.This level of injury experience and exposure to body fluidsis unacceptable and represents a potential risk of cross-infection.Hepatitis B immunization should be considered in this group.Urgent action, including the replacement, wherever possible,of annealed with tempered bar-glassware, is necessary to protectbar workers from glass injury.     

Prevalence of hepatitis B and C virus infection in barbers in the Sivas region of Turkey

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are among the most devastating health problems in the world, including Turkey. The route of transmission of HBV and HCV is mainly parenteral, a small number of epidemiological studies demonstrating that perinatal, sexual, household and occupational transmission occurs. Contact of a patient's blood or bodily fluids with non-intact skin is another mode of HBV and HCV transmission. Barbers in Turkey may often be exposed accidentally to the blood and bodily fluids of their customers. The aim of this study was to determine the prevalence of HBV and HCV infection in barbers. We conducted a study to determine the prevalence of antibodies against HBV and HCV among 176 barbers and 180 control subjects in the Sivas region of Turkey. The prevalence of HBV and HCV was found to be higher in barbers (39.8 and 2.8%, respectively) than in a comparison group (28.3 and 1.1%, respectively). No significant relationship was found with the duration of occupation. Among the seropositive subjects, it was found that most had been exposed to needle pricks or scissor cuts. Our data suggest that both HBV and HCV infections may constitute occupational hazards for barbers. The sources of infection could be not only such personal risk factors as 'sharps' injuries and scissor cuts, but may also include other unknown factors.     

Hepatitis B transmission through blood and body fluids exposure of school personnel

BACKGROUND: Hepatitis B transmission from students to members of staff has been documented in schools, particularly nurseries and day care centres. AIMS: To investigate the frequency of exposure to blood and other body fluids within day schools and to document practices adopted by school personnel to avoid direct contact and decontaminate the environment. METHODS: Questionnaire survey among 21 public day schools in Malta. RESULTS: Episodes of significant blood exposure were rare, occurring at frequencies of 0.071 [95% confidence interval (CI): 0-0.148] incidents per thousand student days. Contact with larger volumes of other body fluids, namely urine and vomitus, was more likely: 0.12 (95% CI: 0.008-0.383) and 0.088 (95% CI: 0.048-0.128) episodes per 1000 student days, respectively. School personnel generally used correct personal protective equipment, particularly gloves, in cases of contact with blood and body fluids. Environmental disinfection methods varied considerably with only 38% of schools (95% CI: 21-59%) using recommended hypochlorite preparations. CONCLUSIONS: Exposure to quantities of blood sufficient to result in HBV transmission in day schools is rare. Emphasis should be placed on risk assessment at individual school level, concentrating on correct management of body fluid exposures through effective staff education.     

Auditing stress

Stress is now recognized as an occupational hazard and it is incumbent on all employers to carry out an assessment in order to assess the risk to health. A stress audit would be an appropriate tool to use. An audit should concentrate on organizational issues. Most audits use a questionnaire and it is sensible to use one which has already been validated. Results should be fed back to the employer in a form which is easily understandable and which contains clear recommendations for action. A repeat audit after one year is advised.     

Hepatitis B, vaccination and healthcare workers

Hepatitis B viral infection is transmitted in adults by transfer of body fluids containing the virus. The outcomes following infection can be significant in terms of both health and employment. It is for these reasons that effective preventative health care is the goal of occupational health practitioners. This evidence-based review of the literature provides a basis upon which practice can be established and highlights some of the issues that may confront practitioners of the future.     

Hepatitis B--are surgeons putting patients at risk?

The 1993 Department of Health guidelines permit a surgeon who is hepatitis B surface antigen (HBsAg) positive but e-antigen (HBeAg) negative to perform exposure prone procedures, unless demonstrated to have infected patients. However, there is increasing evidence of transmission of hepatitis B to patients from health care workers in this supposedly low infectivity category. The Occupational Physician must decide whether existing guidelines represent an adequate risk assessment and indeed whether this is an acceptable risk for patients. If an NHS Trust continues to follow these guidelines it may be in breach of its duty of care to patients. Yet refusing to allow such carriers to operate without testing for additional serological markers may be unlawful discrimination. Further research is clearly needed as well as an urgent review of the guidelines.     

The risk of heat exhaustion at a deep underground metalliferous mine in relation to body-mass index and predicted VO2max

The risk of heat exhaustion at a deep underground metalliferous mine was assessed in relation to the body-mass index (BMI) and predicted maximal oxygen uptake (VO2max) of miners, using case-control methodology. Sixty-five cases of acute heat exhaustion and 119 controls were studied. Heat exhaustion cases had a significantly higher BMI than controls (P = 0.006). The odds ratios increased with BMI. For a BMI of 32.00-36.99, compared to a BMI of less than 27.00 the odds ratio was 3.63 (95% confidence interval, 1.42-9.36). VO2max was not significantly lower in cases than controls. The odds ratios for heat exhaustion increased with decreasing VO2max, but not significantly. The sample size provided 80% power of detecting an odds ratio of 2.5 or greater. Deep underground miners should be advised to maintain a BMI of 24-27. Selection of miners on the basis of BMI should not be used as an alternative to satisfactory engineering controls such as ventilation and refrigeration.     

Risk factors for cytomegalovirus seropositivity in a population of day care educators in Montréal, Canada

BACKGROUND: Horizontal transmission of cytomegalovirus (CMV) is common in the day care setting. Day care educators appear to be at a high risk of infection; however, studies are limited. AIMS: To determine the proportion of CMV-seropositive female educators in the day care setting and to identify associated risk factors. METHODS: Educator- and day care-level risk factors for CMV seropositivity were obtained by questionnaires from day care educators and directors, respectively. Sera were collected from educators and analyzed by enzyme-linked immunosorbent assay. Significant independent risk factors for CMV seropositivity were determined using a multivariable logistic regression model which was fitted using the generalized estimating equation method. RESULTS: CMV seroprevalence in 473 female educators from 81 day care centers in Montréal, Canada, was 57%. Significant risk factors for CMV seropositivity were (i) increasing age (OR5-yr = 1.19; 95% CI = 1.05-1.35), (ii) low-income country of birth (OR = 10.23; 95% CI = 2.64-39.50) or middle-income country of birth (OR = 4.99; 95% CI = 2.39-10.40), (iii) having > or =2 children of their own (OR = 1.98; 95% CI = 1.19-3.31) and (iv) child-to-educator ratio >6 (18-35 months old) in a day care center (OR = 1.87; 95% CI = 1.25-2.81). CONCLUSIONS: Day care educators have risks for CMV infection related to their work in the day care setting, as well as personal risk factors. A review of current guidelines for the prevention of CMV infection in day care is needed to ensure that recommendations are evidence based.     

Occupational exposure to HIV and post-exposure prophylaxis in healthcare workers

Healthcare workers are at risk of occupationally acquired HIV infection primarily due to percutaneous exposure to HIV infected blood. The average risk of HIV transmission after such exposure is approximately 0.3%. There is evidence of higher risk for exposures involving an increased volume of blood (deep injury, injury with a device visibly contaminated with source patient's blood and a procedure which involved a needle placed in the source patient's artery or vein) and exposures to source patients with a high viral load. Triple therapy with two nucleoside analogues (zidovudine, lamivudine) and a protease inhibitor (indinavir) is now widely used for post-exposure prophylaxis following occupational exposure to HIV. Most of the evidence for the efficacy of prophylaxis is based on zidovudine monotherapy. Little is known about the long-term toxicity of these drugs in non-infected individuals. Their use in these circumstances requires careful assessment of possible risks and benefits.     

Are endoscopy nurses at risk of infection with Helicobacter pylori from their work?

BACKGROUND: In response to studies suggesting risk of occupational transmission of Helicobacter pylori (HP) to endoscopy staff, this cross-sectional study of seroprevalence to HP in gastroscopy nurses working in West of Scotland hospitals (an area of high endemicity of HP infection) was performed to determine if they were at excess risk relative to peers working in surgical specialities but without gastroscopy exposure. The study aimed to fulfil employer's duties to carry out a suitable risk assessment required by health and safety legislation. METHOD: This cross-sectional study compares the seroprevalence of HP in gastroscopy nurses and comparators drawn from orthopaedic and trauma units in 10 hospitals during 1998. A directly administered questionnaire collated exposure information on occupational and non-occupational risk factors for infection. Venepuncture was performed for latex agglutination test for IgG to HP. Confounding by socio-economic factors was controlled for by multivariate analysis. RESULTS: Of the 222 participants, 74 were endoscopy staff (84% response) and 148 (59%) were comparators. Of these, 32.4% of gastroscopy and 33% of comparators were seropositive for HP (OR 0.97, P > 0.9, 95% CI 0.5-1.8). No association was found between gastroscopy exposure variables (frequency, years) or exposure to all endoscopy procedures and HP. Significant associations were found for age, childhood deprivation and greater number of siblings. CONCLUSION: No excess HP infection was found in gastroscopy nurses. Duties imposed by the health and safety legislation appear discharged by normal infection control procedures. Socio-economic factors are key determinants of HP status.     

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.     

Sharps injuries in UK health care: a review of injury rates, viral transmission and potential efficacy of safety devices

AIMS: To review the literature on sharps injuries and occupational bloodborne virus transmission in health care in the UK and the worldwide evidence for injury prevention of sharps safety devices. METHODS: Literature review by online database and Internet resource search. RESULTS: Twenty-four relevant publications were identified regarding UK reported sharps injury rates. UK studies showed as much as a 10-fold difference between injuries reported through standard reporting systems (0.78-5.15 per 100 person-years) and rates estimated from retrospective questionnaires of clinical populations (30-284 per 100 person-years). National surveillance data from England, Wales and Northern Ireland gives a rate of 1.43 known hepatitis C virus or human immunodeficiency virus (HIV) transmissions to health care workers per annum. When extrapolated, this suggests an approximate rate of 0.009 such viral transmissions per 1000 hospital beds per annum. Risk of infection from sources with no risk factors is extremely small (less than one in one million for HIV transmission based on Scottish data). Thirty-one studies on the efficacy of sharps safety devices showed evidence of a reduction in injuries, with the greatest reductions achieved by blunt suture needles and safety cannulae. CONCLUSIONS: Although injuries remain common, confirmed viral transmission in the UK has been relatively rare. The degree of under-reporting of sharps injuries may be as much as 10-fold. Safety-engineered devices are likely to be effective at injury reduction.     

Biological monitoring of workers exposed to dimethylformamide in a textile polyurethane unit

Dimethylformamide (DMF) is a universal solvent noted for its solubility in both aqueous and lipid media. It is hepatotoxic, and there are concerns about its carcinogenicity. Our objective was to determine the correlation between air monitoring measurements and biological measurements of a suitable metabolite of DMF in a cohort of operatives in a polyurethane production unit. This was done with a view to assessing how much the inhalation route contributed to total DMF exposure, mainly for control purposes. We investigated the relationship between personal air sample measurements of DMF and biological measurements of N-methylformamide (NMF) in nine adult subjects, recruited across the shifts, with varying levels of exposure to DMF. Personal exposure monitoring was carried out with a low-flow-rate Model 222-4 SKC pump, while post-shift urine samples were obtained for further analysis. Operatives were asked to abstain from consuming alcohol for 24 h before the designated shift, as advised by the laboratory responsible for the analysis of urine samples. We found a very strong statistical association between air sample measurements of DMF and NMF in the urine of the sample population (R(2) = 0.95, P < 0.0001). This study suggests that airborne exposure contributes significantly to elevated levels of NMF and, therefore, indicates that efforts should be concentrated on engineering controls in reducing workplace DMF exposure.     

Is service with the parachute regiment bad for your health?

Military parachuting is perceived to be a 'high risk' activity. The estimate of risk should be based on a comparison of injury rates between soldiers who are military parachutists and soldiers who are not military parachutists rather than the rate of injury per parachute descent. Since other aspects of military life also have an inherent risk of injury the risk attributable to military parachuting must be assessed in this context. The aim of this paper is to determine whether Parachute Regiment soldiers have a greater risk of injury as compared with non-Parachute Regiment infantry soldiers by comparing rates of hospital admission and medical discharge between the two groups. Records at the Defence Analytical Services Agency were analysed for the 10-year period 1987-96. The mean rate of hospital admission for Parachute Regiment soldiers was 50.1 per 1,000 and for infantry soldiers was 50.8 per 1,000 [relative risk (RR) = 0.98; 95% confidence interval (CI) = 0.92-1.04). The mean rate of medical discharge for Parachute Regiment soldiers was 4.9 per 1,000 and for infantry the mean rate was 2.8 per 1,000 (RR = 1.76; CI = 1.45-2.15). This study has shown a methodology for comparing occupational exposure to risk that could be extended to other groups if they can be separated by appropriate criteria.     

Communicating health risk.

Health risk communication is a two way interactive process that involves the exchange of information among interested parties about the nature, magnitude, significance, or control of a risk. Although it has only recently become a topic for scientific research, much has been learned in relation to the strategies and the techniques that contribute to effective health risk communication. In parallel, there has probably never been a time of greater need for effective training in health risk communication. The media and the general public are now very hazard conscious, subsequent to apparently regular events in the areas of public health, safety and environmental issues. Public concern regarding such issues is sometimes much less than experts feel to be appropriate, whilst at other times concern has outstripped the concern of the experts involved. Health professionals trained in the techniques of health risk communication are a vital resource in ensuring that the workforce or the population is properly informed so as to exercise appropriate decisions and actions in relation to hazard and risk.     

A Comparison of Cardiovascular Risk as Measured by Compound Blood Lipid Indices and Two Indices including Lifestyle Factors in Occupational Health Service

Healthy employees in a non-manufacturing firm (n = 252) weredivided into low and high cardiovascular risk subjects in orderto compare different indices of cardiovascular risk for usein occupational health service. The levels of total cholesterol(TC), a compound index of blood lipid components, the ‘atherogenicindex’ (ATH-index) defined as ([TC-HDLc] x [apoB])/(HDLc]x [apoA]), and two other compound indices, one Norwegian (Westlund)and one Scottish (Dundee score) were compared. Information onsmoking habits and blood pressure were part of the two lastindices. Out-off values to separate between low and high risksubjects were defined with TC = 6.5mmol/l, HDLc = 0.9mmol/l,apoA = 1.8g/l and apoB = 1.3g/l, all values based on clinicalguidelines in Norway. No smoking and a systolic blood pressure< l50mmHg was included as cut-off of the combined indices.According to the three indices (ATH, Westund and Dundee) 102,25 and 116 employees were allocated to the increased risk group.Persons allocated to the increased risk group by the combinedindices and not by the compound index were practically all smokers.Systolic blood pressure differed between indices only for personswith extreme pressures. A compound blood lipid index of CV risk,which may be drawn easily in an occupational health settingin an unfasting state and sent by post to a laboratory, mimicsthe allocation of persons to an increased risk group using combinedindices. Smokers with normal lipid values would be allocatedto increased risk by the combined indices, but not necessarilyby the compound index. The use of the compound index togetherwith advice to stop smoking is suggested as a time-saving strategy.     

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.     

What is the risk associated with being a qualified military parachutist?

Military parachuting has been recognized as a hazardous activity since it was first introduced in World War II. Other risks associated with military service include actual war-fighting, training with weapons and explosives, operating with armoured vehicles or deployment to climatic extremes. These other hazards should be considered in any assessment of the additional risk associated with military parachuting. The aim of this study was to identify the risk attributable to parachuting amongst US Army enlisted soldiers. This study identified a cohort of infantry soldiers who served between 1990-94. They were separated by receipt of parachute hazardous duty pay. There was a total of 329,794 person-years (PY) available for study of which 18% were in the exposed group. The rate of hospitalization was very similar in both groups [123.9 per 1,000 PYs for the exposed group, 127 in the non-exposed group: relative risk (RR) = 0.98, 95% confidence interval (CI) = 0.96-1.00). The exposed group was 1.49 times (CI = 1.42-1.57) more likely to be admitted as a result of an injury as compared with the non-exposed group. Military parachuting was 20 times (CI = 16.6-24.3) more likely to be the cause of an injury. This study has shown that receipt of hazardous duty pay for military parachuting can be used as a marker in identifying significant additional risks to the health of infantry soldiers associated with military parachuting. This was reflected in an increased incidence of admission for acute injury and musculoskeletal trauma (particularly a trauma pattern associated with parachuting) as a result of military parachuting. Other risks, which are associated with parachute pay, are admission for the effects of heat, battle injury and helicopter accidents.     

Is atopy and smoking important in the workplace?

The relationship between the respiratory system and the environment involves a complex dynamic interaction of genetic susceptibility, host defence and toxicity. The chance of an individual developing a respiratory disease is dependent on genetic susceptibility and subsequent hereditary risk factors, life-style risk factors and the amount and nature of the exposure that may be encountered in the working environment. Atopic status is an important pre-existing risk that a worker may bring to the workplace (occupational asthma/rhinitis to high molecular weight agents). Smoking is an avoidable additional risk for certain occupational diseases (occupational asthma/bronchitis/cancer) while it can be protective in other circumstances (allergic alvcolitis). More controversially, smoking in some workers may put at increased risk the health of colleagues (passive smoking). This article attempts to clarify the issues surrounding the interaction of atopy, smoking and the workplace.