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Understanding Hepatitis B Blood Tests Understanding your hepatitis B blood test results can be confusing.

It is important to discuss your test results with your health care provider so that you can clearly understand whether you have a new infec- tion, chronic infection, or have recovered from an infection. You may want to take this sheet with you to your appointment as a reference guide. In addition, it is helpful if you request a written copy of your blood tests so that you can be sure you know which tests are positive or negative. Before explaining the tests, there are two basic medical terms that you should be familiar with: Antigen: A foreign substance in the body, such as the hepatitis B virus. Antibody: A protein that your immune system makes in response to a foreign substance. Antibodies can be produced in response to a vaccine or to a natural infection. Antibodies usually protect you against future infections. The test that is used to help you understand your hepatitis B status is called the hepatitis B blood panel. This is a simple 3-part blood test that your doctor can order. Your results can be returned within 7-10 days. The 3-part hepatitis B blood panel includes the following: 1. Hepatitis B Surface Antigen (HBsAg): The "surface antigen" is part of the hepatitis B virus that is found in the blood of someone who is infected. If this test is positive, then the hepatitis B virus is present. 2. Hepatitis B Surface Antibody (HBsAb or anti-HBs): The "surface antibody" is formed in response to the hepatitis B virus. Your body can make this antibody if you have been vaccinated, or if you have recovered from a hepatitis B infection. If this test is positive, then your immune system has successfully developed a protective anti- body against the hepatitis B virus. This will provide long-term protection against future hepatitis B infection. Some- one who is surface antibody positive is not infected, and cannot pass the virus on to others. 3. Hepatitis B Core Antibody (HBcAb or anti-HBc): This antibody does not provide any protection or immunity against the hepatitis B virus. A positive test indicates that a person may have been exposed to the hepatitis B virus. This test is often used by blood banks to screen blood donations. However, all three test results are needed to make a diagnosis. Use the following chart to help you and your doctor interpret your blood panel results: Hepatitis B Foundation ・

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18902 ・ 215-489-4900 ・ [email protected] Tests Results Interpretation Recommendation HBsAg HBsAb HBcAb Negative (-) Negative (-) Negative (-) NOT IMMUNEC has not been infected but is still at risk for possible future infection C needs vaccine Get the vaccine HBsAg HBsAb HBcAb Negative (-) Positive (+) Negative or positive (-/+) IMMUNE C has been vaccinated or recovered from previous infection C cannot infect others Vaccine is not needed HBsAg HBsAb HBcAb Positive (+) Negative (-) Negative or Positive (-/+) ACUTE infection or CHRONIC infec- tion C hepatitis B virus is present C can spread the virus to others Find a knowledgeable doctor for further evaluation HBsAg HBsAb HBcAb Negative (-) Negative (-) Positive (+) UNCLEAR C several interpretations are possible C all

3 tests should be repeated Find a knowledgeable doctor for further evaluation Hepatitis B Foundation Cause for a Cure www.hepb.org What is hepatitis B? Hepatitis B is the world's most common serious liver infection. It is caused by the hepatitis B virus (HBV) that attacks liver cells and can lead to liver failure, cirrhosis (scarring) or cancer of the liver later in life. Approximately 90% of healthy adults who are exposed to the hepatitis B virus (HBV) recover on their own and de- velop the protective surface antibody. However, 10% of infected adults, 50% of infected children and 90% of in- fected babies are unable to get rid of the virus and develop chronic infection. These people need further evaluation by a liver specialist or doctor knowledgeable about hepatitis B. Who should be tested? HBV is transmitted through contact with blood or infected bodily fluids, through unprotected sex, unsterile needles, and from an infected mother to her newborn during the delivery process. HBV is not transmitted casually, through the air, or from casual social contact (hugging, coughing, sneezing). The following groups are especially at high-risk for infection and should be tested: ? Health care workers and emergency personnel ? Partners or individuals living in close household contact with someone who is infected ? Individuals who have had multiple sex partners or who have been diagnosed with an STD ? Injection drug users ? Men who have sex with men ? Individuals who received a blood transfusion prior to