Hepatitis B surface antibody is not lifelong and the value of hepatitis B surface antibody decreases year by year, so it is necessary to monitor the change of the quantitative five indicators of hepatitis B once a year. If the hepatitis B surface antibody titer is less than 100 IU, a booster shot is recommended, especially for people with a family history of hepatitis B disease. For hepatitis B, it is currently preventable and controllable. The most important thing to prevent hepatitis B at present is vaccination. As long as the vaccine is administered and surface antibodies to hepatitis B are produced, you basically will not be infected with hepatitis B. All you need to do is to monitor the changes in the surface antibody values of hepatitis B. In addition, after antiviral treatment, the number of viruses in hepatitis B patients will continue to decline until it is undetectable. Such patients are basically not infectious.