What does the medical abbreviation HBSAB mean?

The medical abbreviation HBsAB stands for Hepatitis B Surface Antibody. It is a serological marker that indicates the presence of antibodies against the Hepatitis B virus (HBV) surface antigen. The presence of HBsAB in a person's blood indicates that they have been exposed to HBV and have developed immunity against the virus. It can be detected in the blood several weeks after infection with HBV or after receiving the hepatitis B vaccine. The presence of HBsAB is used to assess the immune response to HBV infection or vaccination and to determine immunity to the virus.