Incident hepatitis C virus in women with human immunodeficiency virus infection.

Individuals infected with human immunodeficiency virus type 1 (HIV-1) are frequently coinfected with hepatitis C virus (HCV). Acute HCV infection is often asymptomatic and poorly understood. We conducted a historical prospective study of HCV antibody and viremia in plasma samples obtained during 1994-1999 from a cohort of initially HIV-1-infected, HCV-uninfected women and from HIV-1-HCV-uninfected women. Twenty-two (1.5%) of 1517 experienced seroconversion. Of these, 14 (64%) truly acquired a new infection as assessed by enzyme immunoassay response and new-onset viremia. The incidence rate in HIV-1-infected women was 2.7 cases per 1000 person-years; it was 3.3 cases per 1000 person-years in HIV-1-seronegative women (relative risk, 1.21; P=.75). Acquisition of HCV was associated with any history of drug use (P<.01). Five of 12 viremic, seroconverting individuals cleared viremia. Incident HCV infection among HIV-1-infected and HIV-1-uninfected women was low. It was linked to drug use and commonly resolved.