Seroprevalence, viremia and genotype distribution of hepatitis C virus: A community-based population study in northern Italy

Background: Our aim was to define the burden of HCV infection and the related risk factors in a sample of the general population of northern Italy. Materials and Methods: This is a survey on the prevalence of hepatitis C virus (HCV) infection carried out in a cohort (861 males and 1,293 females aged 17-67 years) from the general population of northern Italy. Results: The crude HCV seroprevalence rate was 3.3%, higher in females than in males (p < 0.01) and with a clear age-related effect (test for Linear trend: p < 0.01). When adjusted for sex and age in relation to the reference population, the prevalence was 3.7% ( 95% CI: 2.9-4.5%). In the univariate analysis, HCV infection was related to intravenous drug use (IVDU) (p < 0.001); transfusion (p < 0.001); tattooing (p = 0.02); chiropodist/manicure (p < 0.001); number of children (p < 0.01); educational Level (p < 0.001). In the multivariate analysis sex, age over 50 years, transfusion, IVDU and tattooing were confirmed as risk factors, while the educational Level seems to be a protective factor. Separate multivariate analysis for mates and females points out that the age shift, the protective effect of education and the number of children as risk factor were present only in females. HCV viremia was detected in the 71.8% of the seropositive, resulting in an infection rate of 2.4% (95% CI: 1.7-3.0%). Genotype 1b accounted for 64.7% of isolates. Conclusion: In the general population of our area, HCV infection is mesoendemic and current infections are mostly sustained by genotype 1b.