Abstract: Summary: A seroepidemiological survey of a group of 291 intravenous drug abusers (IVDAs), 45 household contacts of IVDAs, and 39 laboratory workers has been carried out to determine the prevalence of HIV-1, HIV-2, HTLV-1, and HBV antibodies in the sera, as well as to evaluate the role of various risk factors. Among i.v. drug abusers, the prevalence was 32.3% for HIV-1 and 6.6% for HTLV-1. For both viruses, the total figures did not significantly change from 1985 through 1987, accounting for a slow viral circulation in this group. No seropositivity (HIV-1, HTLV-1) was found among laboratory workers, whereas one subject was found seropositive for HIV-1 among household contacts. From 1985 to 1986, 5 out of 58 subjects seronegative for HIV-1 and 5 out of 82 seronegative for HTLV-1 seroconverted (incidence rates of 8.6 and 6.1%, respectively). From 1986 to 1987, none out of 11 seronegatives for HIV and 1 out of 16 seronegatives for HTLV-1 seroconverted. The total figures for hepatitis B markers were 79.2% among IVDAs, 24.4% among household contacts, and 25.6% among laboratory workers. A significant correlation was found between presence of HBV markers and seropositivity for HIV and HTLV-1. A significant association with HIV-1 seropositivity was found for history of sexual intercourse with HIV-1 seropositive partners and for sexual promiscuity. These data emphasize the important role played by sexual behavior in addition to needle-sharing in the spreading of multiple infections among drug abusers.

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: Injection drug users constitute the largest group of persons infected with the hepatitis C virus (HCV) in the United States, and most new infections occur in drug users. Controlling hepatitis C in the U.S. population, therefore, will require developing, testing, and implementing effective prevention and treatment strategies for persons who inject drugs. Fortunately, a substantial body of research and clinical experience exists on the prevention and management of chronic viral diseases among injection drug users. The need to implement interventions to stop the spread of HCV among drug users is critical. The capacity of substance-use treatment programs need to be expanded to accommodate all who want and need treatment. Physicians and pharmacists should be educated in how to provide access to sterile syringes and to teach safe injection techniques, both of which are lifesaving interventions. The treatment of hepatitis C in drug users requires an interdisciplinary approach that brings together expertise in treating hepatitis and caring for drug users. Treatment decisions should be made individually by patients with their physicians, based on a balanced assessment of risks and benefits and the patient’s personal values. Physicians should carefully assess, monitor, and support adherence and mental health in all patients, regardless of whether drug use is known or suspected. Research is needed to better understand how best to prevent and treat hepatitis C in substance users. In the meantime, substantial progress can be made if existing knowledge and resources are brought to bear.