Weakly positive hepatitis B surface antibodies need to be reinjected with the hepatitis B vaccine, as weakly positive antibodies indicate insufficient resistance to the hepatitis B virus. When exposed to a large amount of hepatitis B virus, the hepatitis B surface antibody will be neutralized quickly, so there is still a possibility of being infected by the hepatitis B virus. For those who are weakly positive, if they have close contact with hepatitis B virus carriers, the antibodies may be gradually consumed and turn negative, and the body has no resistance to hepatitis B at this time. It is recommended that those who have a quantitative surface antibody of <10 units or less should receive the hepatitis B vaccine again, so that the surface antibody number of the body is >10 or more, preferably above 100, so that the resistance to hepatitis B is stronger.