HEPATITIS B SURFACE ANTIGEN (HBsAg)

Clinical Significance:

Transmission is due to parental contact through the exchange of blood and blood products, sexual contact, and perinatal spread from mother to newborn. Clinical manifestations ranges from mild asymptomatic infections to severe fulminant hepatitis. Antibodies to these appear generally after HBsAg has been cleared from the blood stream, usually six months after infection, and its presence represents recovery and lifelong immunity. In chronic carriers no antibody is present.