Hepatitis B is a liver disease caused by chronic infection with the hepatitis B virus (HBV), and is a major cause of cirrhosis, liver failure, and hepatocellular carcinoma (HCC). HBV belongs to the Hepadnaviridae virus family, and is spread primarily through percutaneous exposure or via mucosal contact with the bodily fluids (blood, saliva, or semen) of an infected individual. Acute hepatitis B infection is normally asymptomatic, with only 30–50% of persons aged over five years displaying symptoms.

This Datamonitor Healthcare Disease report contains an Epidemiology module.