After 1 to 2 weeks of infection with the hepatitis B virus, antigens and nucleic acids of the hepatitis B virus appear in the blood, and hepatitis B can be detected by testing for these viral markers. After the hepatitis B virus (HBV) invades the body and reaches the hepatocytes, the viral genomic DNA is replicated in the nucleus of the hepatocytes, transcribed, and the core particles (hepatitis B core antigen, viral nucleic acid, etc.) are synthesized and then transported into the hepatocyte plasma, wrapped in the endoplasmic reticulum and cell membrane with its outer shell portion (surface antigen, etc.), and released from the hepatocytes in the form of germination. HBVDNA appears in the blood soon after HBV infection in adults. HBsAg appears in the blood 1~2 weeks after infection and 11~12 weeks at the latest. HBeAg appears slightly later than HBsAg. HBcAg is mainly present in the core of viral particles and in the nucleus of hepatocytes of hepatitis B patients and is not easily detectable in the blood. These three antigens of hepatitis B virus can stimulate the body’s immune system to produce the corresponding three antibodies, namely HBsAb, HBeAb and HBcAb, but these antibodies usually appear only after the disappearance of their corresponding antigens, so they cannot be used for the diagnosis of HBV infection, which is generally determined by testing HBsAg, HBeAg and HBVDNA to determine whether one is infected with hepatitis B. Therefore, HBsAg, HBeAg and HBVDNA are markers of hepatitis B virus infection, and these indicators can be detected in the blood after 1~2 weeks of virus infection, and if the test result is positive, you should seek medical attention in time.