Relevance of intravenous cocaine use in relation to prevalence of HIV, hepatitis B and C virus markers among intravenous drug abusers in southern Italy.

The purpose of this study was to analyze the relationship between intravenous (i.v) drug use practices and the prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) in 146 heterosexual male i.v. drug users (IVDUs) attending a methadone-maintainance treatment program in Catanzaro, Southern Italy. One hundred and forty-six heterosexual male IVDUs attending a methadone-maintainance treatment program in Catanzaro were interviewed in order to obtain the following information: age, number of drug injections (calculated by multiplying the mean number of daily injections by 365 and then by the number of years of injections), number of injection equipment-sharing partners in the last year, number of sexual partners in the last year and possible IV cocaine use. Their sera were studied for the presence of antibodies to HIV, HBV and HCV by commercial enzyme-linked-immuno-sorbent assays run in duplicate. HIV positive samples were confirmed by Western Blot assay. Sixteen per cent of IVDUs were anti-HIV positive, 40% were anti-HBc positive and 68% were anti-HCV positive. Twenty-three per cent were seronegative and 12% were seropositive for all 3 viral markers. Multiple logistic analysis of HIV, HBV and HCV seropositivities in relation to age, number of drug injections, i.v. cocaine use and presence of injection equipment-sharing partners in the last year, showed that: a) older age (more than 27 years) was significantly associated with all 3 viral infections (mainly with HIV); b) i.v. cocaine use was associated with HBV, but even more with HIV; c) injection equipment-sharing partners in the last year was directly associated with HCV and inversely with HIV. No significant association was observed with the number of drug injections and the number of sexual partners. In conclusion, this study: a) demonstrates a difference of prevalence for HIV, HBV and HCV serum markers in this group of IVDUs from Catanzaro, Southern Italy; b) underlines the importance of i.v. cocaine use in the spreading of HIV; c) emphasizes the need of preventive strategies.