Hepatitis B Virus Tests
Other HBV tests are not done as often:
Hepatitis B core antibody (HBcAb) is an antibody to the hepatitis B core antigen that appears about 1 month after the start of an active HBV infection. It can be found in people who had an infection in the past and in those with long-term (chronic) HBV. It usually is present for life. Blood banks test for this antibody when screening donated blood for hepatitis B.
Hepatitis B core antibody IgM (HBcAbIgM) is another antibody to the hepatitis B core antigen. It indicates an HBV infection that has occurred within the last 6 months. It can also mean that a chronic hepatitis B infection has flared up again.
Hepatitis B e-antibody (HBeAb) shows that the active stage of an acute HBV infection is almost over, and your risk of being contagious is greatly reduced.
A hepatitis B vaccine is available to prevent an HBV infection.
Hepatitis D virus (HDV) testing
Infection with the hepatitis D virus (HDV), or delta agent, occurs only in people who are already infected with the hepatitis B virus (HBV). Vaccination against hepatitis B will prevent hepatitis D infection. Hepatitis D infection is rare in the United States and Canada, except among people who inject illegal drugs and those who are frequently exposed to blood products. The hepatitis D test detects HDV antibodies. A positive test indicates only that you have been infected with HDV-it cannot distinguish between an acute or chronic infection. Another test, the HDV RNA test, is needed to determine whether you have an active HDV infection. It does not distinguish between an acute or chronic infection. This test currently is not available except in research settings.
Since hepatitis B infections can be spread through sexual contact, practice safer sex until your test results are returned.
Why It Is Done
Hepatitis B virus testing is done to:
- Identify the type of hepatitis B virus infection. Testing can determine whether an infection has occurred recently or in the past. Other tests that show how well the liver is functioning are usually done to help make treatment decisions.
- Screen people who have a higher risk of getting or spreading a hepatitis B infection, such as doctors, dentists, and nurses.
- Screen blood donors and donor organs to prevent the spread of hepatitis B.
- Find out if a person has developed antibodies after receiving vaccinations for hepatitis B. The presence of antibodies to hepatitis B virus (HBsAb) means that the vaccinations were effective.
- Find out if abnormal liver function tests are being caused by hepatitis B.
- Monitor how well treatment of chronic hepatitis B is working.