Hepatitis B is a viral infection that affects the liver. Screening for hepatitis B usually involves blood tests to detect markers of the infection. There are several types of hepatitis B screening tests, but the CDC recommends the use of three panel tests that include a hepatitis B surface antigen (HBsAg) test, a hepatitis B surface antibody (anti-HBs) test, and a total antibody to hepatitis B core antigen (anti-HBc) test.