Hepatitis B surface Antigen (HBsAg)
HBsAg is present in individuals with active hepatitis B virus. Hepatitis B is a life-threatening disease and very contagious. Individuals with a positive (detected) result for this test should consult a physician immediately.

Hepatitis B surface Antibodies (HBsAb)
A person who recovers completely from Hepatitis B infection or one who has been successfully immunized against hepatitis B will have the antibodies for HBsAg. However, the level of antibodies will decrease with time and there might be a need for a booster dose if the level falls below the protective range.