Hepatitis B vaccine is a vaccine used to prevent hepatitis B. After vaccination, the vaccine stimulates the body’s immune system to produce protective hepatitis B surface antibodies (anti-HBs), so that the body has immunity against hepatitis B and is not infected by the hepatitis B virus. Hepatitis B vaccination requires 3 doses of vaccination, according to the 0, 1 and 6 months procedure, i.e. after the first vaccination, the second and third doses are given at 1 and 6 months intervals. The vaccination site is intramuscularly in the anterior lateral thigh for newborns and intramuscularly in the middle deltoid muscle of the upper arm for children and adults. Hepatitis B vaccination is given to newborns as early as possible, within 24 hours of birth. For newborns whose mothers are HBsAg-positive, a combination of high-efficiency hepatitis B immunoglobulin and hepatitis B vaccine should be used, i.e., in addition to routine hepatitis B vaccination after birth, hepatitis B immunoglobulin should be administered as early as possible within 24 h (preferably within 12 h after birth) at a dose of ≥100 IU. The protection rate for blocking mother-to-child transmission with hepatitis B vaccine alone is 87.8%, and the protection rate for combined immunization interventions is 91.2-97%. protection rate was 91.2-97%. Once accidental contact with blood and body fluids of HBV-infected patients, HBsAg, anti-HBs, ALT, etc. should be tested immediately. If the person has received hepatitis B vaccine and the anti-HBs is known to be ≥10mIU/ml, no special treatment can be given; if the person has not received hepatitis B vaccine or has received hepatitis B vaccine but the anti-HBs is <10mIU/ml or the level of anti-HBs is unknown If you have not received hepatitis B vaccine or have received hepatitis B vaccine but the level of anti-HBs is less than 10mIU/ml or the level of anti-HBs is unknown, you should immediately inject HBIG 200~400IU and complete the routine 3 doses of hepatitis B vaccine. About 30% of people produce antibodies after the first dose of hepatitis B vaccine, about 50% to 70% after the second, and about 90% after the third, and the protection period of the vaccine generally lasts about 12 years. Some people do not produce antibodies after the vaccine and need a higher dose. There are also a few people who are unable to produce antibodies after multiple high-dose injections due to genetic reasons, and these people should avoid close contact with infectious sources to prevent being infected by the hepatitis B virus. It should be noted that the antibody titer produced after hepatitis B vaccination will gradually decrease over time and should be tested regularly. When the antibody titer is less than 10 IU/mL, the human body will lose immunity to hepatitis B. The hepatitis B vaccine should be replenished in time to ensure the effective titer of anti-HBs in the body for a long time, so as to achieve the purpose of real prevention of hepatitis B virus infection.