What is a hepatitus antigen and what does it do if found in your blood
There are a number of different viruses that can infect your liver, causing hepatitis (inflammation of the liver). These cause type A, B, C, etc., hepatitis. If you are infected with one of these and a laboratory test is performed on a sample of your blood, the test will detect the presence of these viruses, which are called antigens. An antigen is any molecule that can elicit an immune response from the infected host. When the immune response takes place, the host manufactures protein molecules call antibodies which specifically attack the infecting virus. A laboratory test may also look for these antibodies.
If you are positive for the antigen, that means you still have the virus in your body, whether you feel sick or not, and that means you can still spread the disease to others. If you are positive for just the antibodies, that means you've either had a past infection or you have been immunized against hepatitis.
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