Age- and risk factor-based serologic screening for Hepatitis C virus among an Urban, high-risk population.

Hepatitis C virus (HCV) screening among individuals born between 1945 and 1965 (ie birth cohort) may augment risk factor-based screening. We assessed HCV seropositivity among injection drug users (IDUs) and birth cohort members from New York City. We assessed HCV risk factors and seropositivity in 7722 participants from community health, HIV prevention, syringe exchange and drug treatment programmes. A total of 26.6% were HCV seropositive, 55.8% were born between 1945 and 1965, and 82.2% had ever injected drugs. Among all participants, HCV seropositivity was higher among IDUs compared to non-IDUs (60.5% versus 7.7%, odds ratio (OR) = 18.5, 95% confidence interval (CI) [16.2, 21.1], P < .0001) and among birth cohort members compared to non-birth cohort members (31.3% versus 22.3%, OR = 1.6, 95%CI [1.4, 1.8], P < .0001). Within the birth cohort, HCV seroprevalence among IDUs was 68.5% versus 11.8%, OR = 16.2, 95%CI [13.7, 19.3]. After adjustment, HCV seroprevalence was higher in IDUs, previously incarcerated, whites (<42 years) and 'other races' (versus blacks), HIV-infected, those who snorted heroin, those with liver disease history, and those who had sex with an HCV-seropositive partner. HCV seroprevalence among IDU, birth cohort members, was considerably higher than among the general population. In this high-risk, urban population, the association between IDU and HCV seropositivity was approximately ten times that between birth cohort membership and HCV seropositivity.