Heterosexual transmission of hepatitis C in Italy

Data from a surveillance system for type-specific acute viral hepatitis in Italy has been used to evaluate the risk of heterosexual transmission of he patitis C virus (HCV) associated with sexual activity with multiple partner s in subjects greater than or equal to 15 years of age. Hepatitis A cases w ere used as controls. During the period 1991-1996, 1,359 acute hepatitis C and 4,365 hepatitis A cases were recorded among subjects greater than or eq ual to 15 years of age. Intravenous drug use was the most frequent source o f infection (35.9%) reported by HCV cases; two or more sexual partners duri ng the 6 months before disease onset accounted for 34.9% of hepatitis C cas es. Adjusting by multiple logistic regression analysis for the confounding effect of all risk factors considered (blood transfusion, intravenous drug use, surgical intervention, dental therapy, other parenteral exposure), and for age, sex, area of residence, and educational level of subjects, showed that having two or more sexual partners is an independent predictor of the likelihood of hepatitis C (OR = 2.2; 95% Cl = 1.7-2.7). After excluding in travenous drug users and patients transfused with blood from analysis, the increase in the adjusted OR for the association between HCV and the number of sexual partners correlated with the increase in the number of sexual par tners. The risk of hepatitis C was 2.0 times higher (95% CI = 1.4-2.9) for subjects with two sexual partners and 2.8 times higher (95% CI = 2.1-3.8) f or subjects with three or more sexual partners, as compared to subjects wit h less than two sexual partners. These findings suggest that heterosexual t ransmission may play an important role in the spread of hepatitis C in Ital y. (C) 1999 Wiley-Liss, Inc.