Hepatitis B Blood Tests
The “Hepatitis B Panel” of Blood Tests
Only one sample of blood is needed for a hepatitis B blood test, but the “Hepatitis B Panel” includes three parts. All three test results are needed to fully understand whether a person is infected or not. Below is an explanation of the 3-part “Hepatitis B Panel” of blood test results.
- HBsAg (Hepatitis B surface antigen) - A "positive" or "reactive" HBsAg test result means that the person is infected with hepatitis B. This test can detect the actual presence of the hepatitis B virus (called the “surface antigen”) in your blood. If a person tests “positive,” then further testing is needed to determine if this is a new “acute” infection or a “chronic” hepatitis B infection. A positive HBsAg test result means that you are infected and can spread the hepatitis B virus to others through your blood.
- anti-HBs or HBsAb (Hepatitis B surface antibody) - A "positive" or "reactive" anti-HBs (or HBsAb) test result indicates that a person is protected against the hepatitis B virus. This protection can be the result of receiving the hepatitis B vaccine or successfully recovering from a past hepatitis B infection. This test is not routinely included in blood bank screenings. A positive anti-HBs (or HBsAb) test result means you are “immune” and protected against the hepatitis B virus and cannot be infected. You are not infected and cannot spread hepatitis B to others.
- anti-HBc or HBcAb (Hepatitis B core antibody) - A "positive" or "reactive" anti-HBc (or HBcAb) test result indicates a past or current hepatitis B infection. The core antibody does not provide any protection against the hepatitis B virus (unlike the surface antibody described above). This test can only be fully understood by knowing the results of the first two tests (HBsAg and anti-HBs). A positive anti-HBc (or HBcAb) test result requires talking to your health care provider for a complete explanation of your hepatitis B status.