[Seroepidemiologic study of hepatitis C virus infection in a general population from the region of La Rioja, Spain].

BACKGROUND: To assess the prevalence of hepatitis C virus (HCV) infection in a general population and to identify risk factors for acquiring infection. POBLATION AND METHODS: A cross section of the general urban population of La Rioja aged between 14 and 65, was studied by choosing a random sample (n = 890). Serum samples were screened for HCV antibodies by second-generation enzyme-linked immunosorbent assays and recombinant immunoblot assays. We investigated the relationship between HCV serostatus and age, intravenous drug use, tattoos, blood transfusion, history of hepatitis, previous surgical operations, the administration of parenteral treatment and the number of sexual partners. RESULTS: The overall prevalence of anti-HCV antibodies was 2%. The logistic regression analysis confirmed a statistically significant association between anti-HCV positivity and intravenous drug use (OR = 169.67; CI 95%: 21.1-1,364.75), exposure to a blood transfusion (OR = 10.41; CI 95%: 3.03-35.75); tattoos (OR = 9.04; CI 95%: 1.25-65.36), and male sex (OR = 5.35; CI 95%: 1.34-21.42). However, that 38% of subjects had no risk factors for HCV infection. CONCLUSIONS: These results show a high proportion of people were found to have anti-HCV antibodies. The possible mode of infection in one third of these subjects is not known. In the half of these cases the infection was found have been acquired by an intravenous mechanism: blood transfusion or drug use.