Globally, it is estimated that 400 million people are chronically infected with the hepatitis B virus (HBV) and that 10-30 million people become infected with HBV each year. HBV is the leading cause of chronic liver disease and a leading cause of death worldwide, accounting for up to half of all cases of cirrhosis and hepatocellular carcinoma.
Both HBV and HIV are transmitted primarily through sexual contact and injection drug use. Because of these shared modes of transmission, a high proportion of adults at risk for HIV infection are also at risk for HBV infection. HIV-positive persons who become infected with HBV are at increased risk of developing chronic HBV infection and should be tested. In addition, persons who are co-infected with HIV and HBV can have serious medical complications, including an increased risk of liver-related morbidity and mortality.