INCIDENCE AND RISK-FACTORS FOR HEPATITIS-C AMONG INJECTION-DRUG USERSIN BALTIMORE, MARYLAND

Between 1988 and 1996, the incidence of and risk factors for hepatitis C virus (HCV) infection were studied in a cohort of injection drug us ers in Baltimore, Maryland. By second generation antibody testing of s tored serum samples, 142 participants were found to be susceptible to HCV at the time they entered the study, After a median follow-up of 6. 5 years, 43 participants (30.3%) developed antibodies to HCV (anti-HCV ). The overall incidence was 6.4 cases per 100 person-years, but a sub stantial decline in tile annu:ll incidence rate was observed after the first 2 years (1988 to 1990, 13.4/100 person-years; 1991 to 1996, 2.3 /100 person-years [P = 0.0001 for trend]), Participants who acknowledg ed active drug use, especially those who acknowledged frequent use and sharing of drug paraphernalia, were at increased risk of HCV infectio n, However, high-risk sexual practices were not associated with HCV se roconversion. Efforts to reduce HCV infection must be focused on curbi ng drug use and especially on the sharing of needles and drug parapher nalia.