HBs Antibodies (Hepatitis B)

The positivity of HBs antibodies (antibodies to the surface antigen of the hepatitis B virus) is a sign of previous exposure to the hepatitis B virus (HBV), which has resulted in the acquisition of antibody immunity against the virus. The HBs antibody test is of paramount importance in identifying individuals who are not immune to HBV infection and, if positive, is an indication of the efficacy of vaccination against the virus as the antibody titre lasts for years or a whole lifetime.