In our country, most chronic hepatitis B patients are infected with hepatitis B virus when they are infants and children, because the immune function against hepatitis B virus in infancy is not yet complete, so the immune system does not recognize hepatitis B virus and cannot clear it, but treats it as its own and allows it to live in the body, this period is called the immune tolerance period; as the age grows, the immune system gradually becomes complete and Immune cells recognize hepatitis B virus and clear it, because hepatitis B virus exists in liver cells, so immune cells and some antiviral substances secreted by them destroy liver cells and release the virus to destroy it, at this time, because liver cells are destroyed, transaminases increase, and this period is called immune clearance period; but the specific immune function against hepatitis B virus varies greatly among individuals, and some immune function However, the specific immune function against hepatitis B virus varies greatly among individuals, and some immune function is strong enough to clear the hepatitis B virus soon, but some are not very strong, thus causing continuous chronic inflammation and fibrosis in the liver, and over time, some patients develop cirrhosis or even hepatocellular carcinoma. After this period, the virus is suppressed by the immune function, and the virus activity is weakened or stopped, which is then clinically manifested as HBsAg positive, anti-HBe positive, HBV DNA negative, and normal liver function, which is called inactive carrier period (immune control period); however, when the immune function is low, such as when exertion and illness, use of immunosuppressive drugs, chemotherapy, etc., the immune function When the immune function is suppressed, the virus becomes active again and HBV DNA becomes positive, which is called the reactive period. Of course, not everyone has a clear four-stage process, some people can have two stages overlapping together, and some people do not have a particular stage, etc. Therefore, when the body’s immune function has not yet recognized and initiated the clearance of hepatitis B virus (such as the immune tolerance period), the application of antiviral therapy is not appropriate, only when entering the immune clearance period (such as transaminase abnormalities, except those caused by alcohol, drugs, etc.), is the best time for anti hepatitis B virus treatment is the best time.