What does a positive HBcAb test imply?

A positive HBcAb (hepatitis B core antibody) test indicates past exposure to the hepatitis B virus. This marker appears in the blood after a person has been infected with the virus and generally indicates that the individual has had a past hepatitis B infection, even if it was not symptomatic or if the person has since cleared the virus.

HBcAb signals that the individual's immune system has responded to the virus, which could mean they have gone through an acute infection that resolved or potentially a chronic infection that has not been cleared. However, unlike the surface antibody (HBsAb), which indicates immunity from either vaccination or a resolved infection, HBcAb alone does not confirm current immunity or vaccination status. Therefore, its presence is specifically tied to a history of infection, making it a crucial marker in understanding an individual's immune history concerning hepatitis B.