Epidemiology of viral hepatitis and HIV co-infection

Worldwide, hepatitis B virus (HBV) accounts for an estimated 370 million chronic infections, hepatitis C virus (HCV) for an estimated 130 million, and HIV for an estimated 40 million. In HIV-infected persons, an estimated 2-4 million have chronic HBV co-infection and 4-5 million have HCV co-infection. HBV, HCV and HIV share common routes of transmission, but they differ in their prevalence by geographic region and the efficiency by which certain types of exposures transmit them. Among HIV-positive persons studied from Western Europe and the USA, chronic HBV infection has been found in 6-14% overall, including 4-6% of heterosexuals, 9-17% of men who have sex with men (MSM), and 7-10% of injection drug users. HCV infection has been found in 25-30% of HIV-positive persons overall; 72-95% of injection drug users, 1-12% of MSM and 9-27% of heterosexuals. The characteristics of HIV infected persons differ according to the co-infecting hepatitis virus, their epidemiologic patterns may change over time, and surveillance systems are needed to monitor their infection patterns in order to ensure that prevention measures are targeted appropriately. (c) 2005 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.