There are three pairs of immunologic markers for the hepatitis B virus, namely, surface antigen (HBsAg) and surface antibody (anti-HBs or HBsAb), e antigen (HBeAg) and e antibody (anti-HBe or HBeAb), and core antigen (HBcAg) and core antibody (anti-HBc or HBcAb). Since the core antigen is not easily detected in the blood, the “two halves” of the antigen and antibody remain. The significance of the “two halves” test (or Hepatitis B 5) is to find out if the person is infected with Hepatitis B and the specifics of the infection. What are the “two halves”? 1.Hepatitis B virus surface antigen (HBsAg) positive is a sign of hepatitis B virus infection, but does not reflect whether the virus is replicated, the degree of replication and infectiousness. 2.Hepatitis B virus surface antibody (HBsAb) is a kind of neutralizing antibody, HBsAb positive usually means that hepatitis B has recovered or has resistance to hepatitis B virus. If only this item is positive after hepatitis B vaccination, it should be regarded as a normal phenomenon after hepatitis B vaccination. 3.Hepatitis B virus e antigen (HBeAg) positive is the sign of virus replication. If HBeAg is persistently positive for more than 3 months, it often indicates that hepatitis B has a tendency of chronicity. 4.Hepatitis B virus e antibody (HBeAb) is positive as the sign of stopping virus replication, which indicates that the virus replication is reduced and the infectiousness is weaker, but it is not completely free of infectiousness. 5.Hepatitis B virus core antibody (HBcAb) positive is a sign of having been infected or being infected with hepatitis B virus. Among them, core antibody IgM is the sign of recent infection or virus replication. The core antibody IgG is a sign of infection with the hepatitis B virus. Doctors can determine the status and prognosis of hepatitis B infection by using different combinations of the “two halves”. If you find any positive indicator in the “two-half” test report, it is better to consult a specialist. Several common results 1, “triple positive” usually referred to as “triple positive”, that is, surface antigen (HBsAg), e antigen (HBeAg) and core antibody (HBcAb) is positive, while others are negative. Generally speaking, Hepatitis B “triple positive” indicates active viral replication and strong infectiousness, often accompanied by positive Hepatitis B DNA, and the possibility of evolving into chronic hepatitis B is also greater. It should be reminded that “triple positive” is an indicator of the number and activity of hepatitis B virus in the body, which only reflects the status of carrying the virus in the body, and does not reflect the normal liver function, so it cannot be used to determine the severity of the disease. 2.”Small triple positive” Hepatitis B “small triple positive” refers to the surface antigen (HBsAg), e antibody (HBeAb) and core antibody (HBcAb) is positive, and other is negative. A “minor triple positive” means that the hepatitis B virus is replicating in the body, and usually results from a “major triple positive”. e antibody (HBeAb) positivity means that the body has developed a certain degree of immunity to the E antigen. Hepatitis B patients with “minor triple positive” should be examined for HBV-DNA and liver function. If HBV-DNA (+) and liver function is abnormal, it means that hepatitis B virus is active and infectious, if HBV-DNA (-) and liver function is normal, it means that virus replication is not active. If HBV-DNA(-) and liver function is normal, it means the virus replication is not active. 3, “two half” all negative Hepatitis B “two half” all negative, that the body has never been infected with hepatitis B virus, there is no immunity to the hepatitis B virus, it is the indication of hepatitis B vaccination. Adults must check the hepatitis B “two halves” before receiving the hepatitis B vaccine, and can only receive the vaccine if the test indicates that the surface antigen, surface antibody, e antigen, e antibody and core antibody of hepatitis B virus are all negative and the liver function is normal.