Hepatitis B Virus Tests
Hepatitis B virus (HBV) tests check for substances in the blood that show whether a hepatitis B infection is active or has occurred in the past. The tests look for different signs of infection (markers):
- Antigens are markers made by bacteria or viruses. So the presence of HBV antigens means that the virus is in the body.
- Antibodies are proteins produced by the body to fight infection. The presence of HBV antibodies means that you have been exposed to the hepatitis B virus at some time. But you could have been infected long ago and gotten better, or you may have a current infection.