Hepatitis C virus infkction in the United States

Hepatitis C virus (HCV) infection is the most common chronic bloodborne infection in the United States, and most infected persons are younger than 50 years old. The relative importance of the two most common exposures associated with transmission of HCY blood transfusion and intravenous drug use (IVDU), has changed over time. Blood transfusion, which accounted for a substantial proportion of HCV infections acquired >lO years ago, rarely accounts for recently acquired infections. In contrast, IVDU has consistently accounted for a substantial proportion of HCV infectious and currently accounts for 60% of HCV transmission while sexual exposures account for up to 20%. Other known exposures (occupational, hemodialysis, household, perinatal) together account for about 10% of infections. In the remaining lo%, no recognized source of infection can be identified, although most persons in this category are associated