A. De Schryver

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in health care workers (HCWs): guidelines for prevention of transmission of HBV and HCV from HCW to patients

The transmission of viral hepatitis from health care workers (HCW) to patients is of worldwide concern. Since the introduction of serologic testing in the 1970s there have been over 45 reports of hepatitis B virus (HBV) transmission from HCW to patients, which have resulted in more than 400 infected patients. In addition there are six published reports of transmissions of hepatitis C virus (HCV) from HCW to patients resulting in the infection of 14 patients. Additional HCV cases are known of in the US and UK, but unpublished. At present the guidelines for preventing HCW to patient transmission of viral hepatitis vary greatly between countries. It was our aim to reach a Europe-wide consensus on this issue. In order to do this, experts in blood-borne infection, from 16 countries, were questioned on their national protocols. The replies given by participating countries formed the basis of a discussion document. This paper was then discussed at a meeting with each of the participating countries in order to reach a Europe-wide consensus on the identification of infected HCWs, protection of susceptible HCWs, management and treatment options for the infected HCW. The results of that process are discussed and recommendations formed. The guidelines produced aim to reduce the risk of transmission from infected HCWs to patients. The document is designed to complement existing guidelines or form the basis for the development of new guidelines. This guidance is applicable to all HCWs who perform EPP, whether newly appointed or already in post.

Hepatitis B virus, hepatitis C virus and other blood-borne infections in healthcare workers: guidelines for prevention and management in industrialised countries

The Viral Hepatitis Prevention Board (VHPB) convened a meeting of international experts from the public and private sectors in order to review and evaluate the epidemiology of blood-borne infections in healthcare workers, to evaluate the transmission of hepatitis B and C viruses as an occupational risk, to discuss primary and secondary prevention measures and to review recommendations for infected healthcare workers and (para)medical students. This VHPB meeting outlined a number of recommendations for the prevention and control of viral hepatitis in the following domains: application of standard precautions, panels for counselling infected healthcare workers and patients, hepatitis B vaccination, restrictions on the practice of exposure-prone procedures by infected healthcare workers, ethical and legal issues, assessment of risk and costs, priority setting by individual countries and the role of the VHPB. Participants also identified a number of terms that need harmonisation or standardisation in order to facilitate communication between experts.

Hepatitis E virus infection: an emerging occupational risk?

BACKGROUND Hepatitis E virus (HEV) infection is endemic in many developing countries, causing substantial morbidity. Transmission is primarily faeco-oral and is associated with both sporadic infections and epidemics in areas where poor sanitation and weak public health infrastructures exist. Recently, it has become clear that HEV is also an endemic disease in industrialized countries. Moreover, a porcine reservoir and growing evidence of zoonotic transmission have been reported in these countries, suggesting the possibility of occupational transmission to man. AIMS To summarize the current knowledge on the epidemiology and prevention of transmission of HEV infection in occupational settings. METHODS The following key words were used to explore PubMed: hepatitis E, disease, epidemiology, profession(al), occupation(al). RESULTS After screening of the results, 107 publications were retained. In non-endemic regions, seroprevalence varied from a few per cent (2-7.8%) in Europe, Japan and South America to 18.2-20.6% in the USA, Russia, UK, southern France and Asia. A meta-analysis of 12 cross-sectional studies evaluating HEV immunoglobulin G (IgG) seroprevalence in individuals occupationally exposed to swine showed greater odds of seropositivity in the exposed group but also a high degree of heterogeneity. A funnel plot suggested publication bias. CONCLUSIONS There was a significant association between occupational exposure to swine and HEV IgG seroprevalence, but the level of prevalence detected depended also on the type of HEV IgG kits used. Further research, including on mechanisms and risk factors for infection, as well as the development of better serological tests for identification of infection, is required.

The occupational risk of Helicobacter pylori infection among workers in institutions for people with intellectual disability

Objectives: A cross-sectional study to evaluate the occupational risk for Helicobacter pylori infection, on top of other risk factors, in staff members of institutions for people with intellectual disability. In these institutions, the residents had a documented high prevalence of H pylori infection (86% presenting antibodies). As a control group, the study used administrative workers from other companies. Methods: All participants completed a questionnaire concerning sociodemographic characteristics, medical history and employment data and they underwent a serology test. Results: 671 staff members of the institutions and 439 subjects in the control group participated in the study. Prevalence of H pylori antibodies was significantly higher in the study group than in the control group (40.6% vs 29.2%; p<0.001). Crude odds ratio for occupational risk was 1.68; adjusting for the confounding effect of age, gender, body mass index, smoking, tropical journeys and number of household members during childhood resulted in an even higher (adjusted) OR of 1.98 (95% CI 1.42 to 2.69). In multiple logistic regression analysis adjusting for variables shown to be confounders, faecal contact continued to be significantly associated with H pylori infection. Attributable risk was 49.5%. Conclusions: H pylori infection is an occupational risk in healthcare workers working in institutions for people with intellectual disability. We identified faecal contact as an independent occupational risk factor for H pylori infection.

Need for a comprehensive, consistently applied national hepatitis B vaccination policy for healthcare workers in higher educational institutions: a case study from South Africa.

BACKGROUND Hepatitis B virus (HBV) is transmitted by infected blood and other body fluids, placing healthcare workers (HCWs) and student HCWs at increased risk of HBV infection through occupational exposure. AIM To establish the existence, content and implementation of hepatitis B (HB) vaccination policies for student HCWs being trained at higher educational institutions (HEIs) in South Africa. METHODS Self-administered structured questionnaires were sent to 23 nursing colleges and 11 universities in South Africa that train doctors, nurses or dentists. FINDINGS Twelve (35%) questionnaires were returned. Ten HEIs had a policy consisting mainly of recommendations given to students at registration. Nine HEIs made HB vaccinations available, with four HEIs covering the cost through student fees. Seven HEIs did not require a record of previous vaccination. Six HEIs did not accept non-responders (NRs), three HEIs would only accept an NR after receiving a second three-dose vaccination series and counselling, six HEIs regarded an HBV carrier as infectious, and 10 HEIs would accept HBV carriers as students. The low response rate makes it difficult to generalize the results, but may suggest a lack of an HB vaccination policy for student HCWs at non-responding HEIs. CONCLUSIONS Policies of responding HEIs regarding HB vaccination, HBV carriage and response to HB vaccination were variable, sometimes inappropriate and not sufficiently comprehensive to protect student HCWs against occupationally acquired HBV. This emphasizes the need for a comprehensive, consistently applied, nationally coordinated vaccination policy to ensure that student HCWs receive proper protection against HBV infection.

Hepatitis B surface antigenaemia following vaccination with a combined vaccine against hepatitis A and B

Summary.  We report a case of transient hepatitis B surface antigenaemia (HBsAg) following vaccination with a combined vaccine against hepatitis A and B in healthy adults. This phenomenon has been observed following administration of recombinant hepatitis B (monovalent) vaccine, mainly in newborns or dialysis patients. Reports on healthy adults are much less frequent and mostly concern blood donors. The frequency of its occurrence is largely unknown but its duration does not exceed 28 days. It is not detected by all available assays. It is caused by a passive tranfer of antigen by vaccination, and not by viral replication; hence there is no risk for vaccination‐induced infection. An important implication resulting from our findings is that the results of HBsAg assays should be interpreted according to the time elapsed since the last administration of a recombinant monovalent vaccine against hepatitis B or a combined vaccine against hepatitis A and B.

Comparative immunogenicity of two vaccination schedules of a combined hepatitis A and B vaccine in healthy volunteers.

Summary.  In 1996, a combined vaccine against both hepatitis A and B was licensed and commercialized and has been recommended for healthcare personnel in Belgium. This study compares the immunogenicity against hepatitis B virus (HBV) and safety of two vaccination schedules (0–1–12 months and 0–1–6 months) with this vaccine. This is a randomized, stratified and controlled study in healthy adult workers, who are not occupationally exposed to HBV. Seroconversion (≥1 IU/L) and seroprotection (≥10 IU/L) rates were compared using Fisher’s exact test; geometric mean concentrations (GMCs) of anti‐HBs were compared using one‐way ANOVA. All statistical analyses were carried out with SPSS 11 on Apple Macintosh. A total of 399 subjects were enrolled in the study, and 356 were analysed according to the protocol. The rate of ≥10 IU/L at 6 months was 70.6% in the group 0–1–12 and 79.9% in the group 0–1–6; this rate decreased to 55.9% at 12 months in the first group. Seroconversion and seroprotective rates against HBV measured at month 13 in group 0–1–12 (98.9% and 95.6%) and measured at month 7 in group 0–1–6 (99.4% and 97.1%) were not statistically significantly different. GMC of anti‐HBs after the 0–1–12 schedule was more than two fold higher than after 0–1–6 schedule (P < 0.001). Reported side effects were comparable in both groups with a slight tendency to fewer side effects in the 0–1–12 group after the third dose. The results from our study show that the completed schedule 0–1–12 offers at least equal protective immunogenicity against HBV as the completed 0–1–6 schedule. People not receiving their third dose at 6 months can be given this dose up to 12 months after the first dose. The drawback of this flexibility, however, is the longer time period before the protection becomes effective.

520 Probe: hazardous chemical products register for occupational use in belgium

During their job, workers are exposed to a wide variety of working conditions including chemical substances that are potentially detrimental to employees’ health. Today, Belgian data on occupational exposure to dangerous chemicals are collected by Occupational Health Services (OHS) merely for the purpose of assuring the appropriate health screening. This makes these data of little use for epidemiological research and exposure surveillance on one hand and for policy development by competent authorities on the other hand. The PROBE (Hazardous chemical Products Register for Occupational use in Belgium) study is set up to investigate the exposure of Belgian workers to dangerous chemical products, including type, duration and frequency of exposure. PROBE consists of a systematic collection and analysis of occupational chemical exposure data. A trained, motivated, and representative sample of occupational physicians from both internal and external OHS will be invited to participate. The data will be collected on a regular basis over a period of 5 months. Besides demographics, exposure measurements and health related data will be collected. First, a pilot will be kicked off in a limited sample of occupational physicians, testing the feasibility of the program. The final goal of the project is to register in a comprehensive but easy way the exposure to dangerous chemicals in order to improve preventive measures, to ensure workers’ health and to develop a national surveillance policy.

SP5-19 What is the role of occupational transmission in the epidemiology of Helicobacter pylori?

Introduction One of the surprising features of H pylori, is that we still do not know how the organism is usually acquired. Two possible avenues for transmission are direct infection from person to person, or through an intermediary such as the water supply, flies or animals. If transmission is person to person, the organism may be transmitted by faeco-oral, oro-oral, or by gastro-oral route. Methods In order to study some of these aspects we performed a number of cross-sectional studies, the results of which are reported here. Results Faeco-oral transmission: In a cross-sectional study in 587 employees working in 2 institutions for children with mental disabilities with a documented high prevalence of H pylori infection, using multiple regression analysis to adjust for confounding variables, we found an almost 2.5 increased risk in workers having contact with faeces of inhabitants. Other risk factors for H pylori infection were not significant in multiple regression analysis. In another cross-sectional study in 198 nursing home workers, the age-adjusted prevalence of H pylori was not higher than in a reference population and no association with any other risk factors was found. Waterborne transmission: In a cross-sectional study in 317 wastewater workers, the age-adjusted prevalence of H pylori was not higher than in a reference population and there was no association with any activity by which workers were exposed to wastewater. Conclusions Results of our studies show the difficulty in interpreting cross-sectional studies. There is a need for cohort studies with an exact exposure assessment to all possible transmission routes.