Signs and Symptoms
HBsAg (hepatitis B surface antigen) - This refers to the outer surface of the hepatitis B virus that triggers an antibody response. A "positive" or "reactive" HBsAg test result means that the person is infected with the hepatitis B virus. This can be an "acute" or a "chronic" infection. Infected people can pass the virus on to others through their blood.
HBsAb or anti-HBs (hepatitis B surface antibody) - This refers to the protective antibody that is produced in response to an infection. It appears when a person has recovered from an acute infection and cleared the virus (usually within six months) or responded successfully to the hepatitis B vaccine shots. A "positive" or "reactive" HBsAb (or anti-HBs) test result indicates that a person is "immune" to any future hepatitis B infection and is no longer contagious. This test is not routinely included in blood bank screenings.
- HBcAb or anti-HBc (hepatitis B core antibody) - This refers to an antibody that is produced in response to the core-antigen, a component of the hepatitis B virus. However, this is not a protective antibody. In fact, it is usually present in those chronically infected with hepatitis B. A "positive" or "reactive" HBcAb (or anti-HBc) test result indicates a past or present infection, but it could also be a false positive.