I had Hep B surface antigen test twice two years after possible exposure. Both times negative. I thought this was it I am negative but now I see that this test is accurate only for window period less than 3 months. Can you confirm which test to give to exclude the possibility and have conclusive result.
The test for hepatitis B infection is to test for the presence of Hep B surface antigen in the serum. It may not appear immediately after an infection, but it should appear several weeks afterward. It disappears after 6-12 months in case of acute Hepatitis B, but will persist after 6-12 months in case of chronic Hepatitis B.