Abstract: Concern is increasing among surgeons and operating theatre staff about the risks of occupational exposure to HIV and hepatitis viruses.’-6 There has also been much public debate about the risk of patients who undergo invasive procedures acquiring these viruses from infected surgeons.7 Eminent bodies have published reports on the topic, yet views vary about the risk of transmission of HIV8-’4 and the level of precautions appropriate to British hospitals.’59 It was against this background that in October 1991 the Hospital Infection Society and the Surgical Infection Study Group convened a one day workshop at the Royal Society of Medicine, London, to review the degree of risk and prepare practical guidelines for surgeons, anaesthetists, and health care workers working in operating theatres. Its report forms the basis of the recommendations presented below. The incidence of nosocomially acquired hepatitis far exceeds that of HIV infection. Hepatitis B is preventable with immunisation and hence is discussed first.

Abstract: Objective: To determine whether frontloading (i.e., syringe-mediated drug-sharing) is a risk factor for HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) infection among injecting drug users (IDU). Design: Cross-sectional study. Data on sociodemographic and behavioural characteristics were obtained by a standardized questionnaire. Serum samples were tested for seromarkers for HIV, HBV and HCV. Setting and participants: IDU were recruited at ’low-threshold’ storefront agencies (out-of-treatment sample), and at a centre for long-term drug use treatment (in-treatment sample). Individuals were included in the study if they had injected drugs within the previous 3 months. Main outcome measures: Serological evidence for HIV, HBV, HCV exposure. Results: Of all IDU (n = 324), 84% had ever practised frontloading with non-sterile injecting equipment, and 46% had done so more than 100 times; 32% had front-loaded during the 6 months prior to the interview. The crude seroprevalence rates for HIV, HBV and HCV increased with the overall frequency of frontloading, and reached 22, 71 and 94%, respectively, among IDU who had frontloaded more than 100 times. After controlling for confounding effects by logistic regression, having practised front-loading more than 100 times was significantly associated with HIV infection [adjusted prevalence odds ratio (POR) 3.5; 95% confidence interval (CI), 1.4-9], and HCV infection (adjusted POR, 5.4; 95% CI, 2.3-12), but not with HBV infection. Another independent risk factor for all three virus infections was needle-sharing in prison. Conclusions: In communities where sterile injection equipment is readily available, and IDU have substantially reduced their overall levels of needle-sharing, the practice of frontloading appears to be a major risk factor for infections by blood-borne viruses among IDU. Prevention activities should specifically address this risk behaviour.

Abstract: Concerns about the risks of HIV infection among drug injectors have eclipsed concerns about the prevalence and transmission of hepatitis, and in particular hepatitis B virus infection. Findings are reported from surveys undertaken with two separate community-recruited samples of drug injectors in London collected in 1992 (n = 505) and in 1993 (n = 507). Anonymized confirmed testing of saliva snows 51.5% of drug injectors in 1992 and 47.9% in 1993 to be antibody positive to the core antigen of hepatitis B virus (anti-HBc). Approximately half of the drug injectors confirmed as anti-HBc positive were unaware that they had been infected with hepatitis, Anti-HIV-1 prevalence was considerably lower at 7.0% in 1992 and 6.9% in 1993. Multivariate analyses showed anti-HBc positivity to be most likely among older injectors with longer injecting careers who had a history of having shared used needles and syringes. HIV-1 positivity was also associated with a history of having shared injecting equipment as well as with recent sharing (i.e. in the last 6 months). Unlike anti-HBc positivity, there were no associations between HIV-1 positivity and age or length of injecting career. Younger injectors with shorter injecting careers were more likely to report recent sharing of used injecting equipment than older injectors with longer injecting careers. We note the potential for continued transmission of HBV and HIV-1, particularly among younger injectors. We recommend an integrated strategy to maximize the health of drug injectors, of which HIV and HBV prevention is a part. There is a need to widen the availability of HBV vaccinations for HBV negative drug injectors and their sexual partners and for clear guidelines to drug injectors about the relative efficacy of bleach to disinfect injecting equipment of HBV and HIV.

Abstract: Harm reduction strategies for the prevention of transmission of human immunodeficiency virus (HIV) transmission among injecting drug users (IDUs) have been widely implemented in Australia and are seen to have been effective in preventing the spread of HIV. A major strategy has been increasing the availability of and accessibility to methadone maintenance therapy (MMT) programmes. We have reviewed the experience of a major MMT general practice with hepatitis C virus (HCV) infection from 1991 to 1995. Of 1741 individuals tested for HCV antibodies at least once 66.7% were positive. Of 73 IDUs who were initially seronegative and were retested at least once, 19 were subsequently seropositive. Seroconverters to HCV were younger than non-seroconverters, and were more likely to have evidence of previous hepatitis B infection. The overall HCV incidence rate was 22 cases per 100 person-years, and this did not differ between those on MMT programs (continuous or interrupted) between HCV tests and those not on MMT. These findings suggest that the role of MMT in the control of the spread of HCV infection among IDUs needs further assessment, and that control of the current epidemic of HCV infection among IDUs in Australia will be very difficult.