The second positive item of the hepatitis B half refers to the positive surface antibody of hepatitis B. Such patients are protected and will not be infected with hepatitis B. The second positive item of the hepatitis B half refers to the positive surface antibody of hepatitis B. For those who are negative for hepatitis B surface antibody, they need to be vaccinated with the hepatitis B vaccine, which is routinely given in three doses. For people with positive surface antibodies to hepatitis B, no special treatment is needed. If there is a person with hepatitis B in the family, it is recommended to dynamically monitor the change in the value of hepatitis B surface antibody titer, and if the value is less than 100 IU then a booster shot is needed.