1.Hepatitis B vaccine prevention Vaccination against hepatitis B is the most effective way to prevent HBV infection. The targets of hepatitis B vaccination are mainly newborns11 , followed by infants and children, unimmunized people under 15 years old and high-risk groups (such as medical personnel, people who are often in contact with blood, staff of childcare institutions, organ transplant patients, people who often receive blood transfusions or blood products, people with low immune function, family members of HBsAg-positive people, men who have sex with men, people with multiple sexual partners and people who inject drugs intravenously). The vaccine should be administered to all patients (including those who have received blood transfusions or blood products). Three doses of hepatitis B vaccine are required for the entire course, according to the 0, 1, and 6 month schedule, i.e., after the first dose of vaccine, the second and third doses are given at intervals of 1 month and 6 months. For adults, three doses of 20 μg recombinant yeast hepatitis B vaccine or 20 μg CHO recombinant hepatitis B vaccine are recommended. For those who are immunocompromised or non-responders, the vaccine dose (e.g. 60 μg) and number of doses should be increased; for those who do not respond to the 3-dose immunization program, another 60 μg or 3 doses of 20 μg recombinant yeast hepatitis B vaccine can be administered, and the anti-HBs in the serum should be tested 1~2 months after the second hepatitis B vaccination. 2. Prevention after accidental contact When there is a broken skin or mucous membrane after accidental contact with the blood and body fluids of HBV-infected person, it can be treated as follows20: 1. Serological testing: HBV DNA, HBsAg, anti-HBs, HBeAg, anti-HBc, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) should be tested immediately, and within 3 and 6 months retest. 2. Active and passive immunization: If you have received hepatitis B vaccine and are known to be anti-HBs positive, you may not have special treatment. If you have not received hepatitis B vaccine or have received hepatitis B vaccine but the anti-HBs is <10 IU/L or the level of anti-HBs is unknown, you should immediately inject 200-400 IU of HBIG and receive one dose of hepatitis B vaccine (20(g)) at different sites at the same time, and receive the second and third doses of hepatitis B vaccine (20(g) each) 1 month and 6 months later respectively. After being positive for hepatitis B antibody, you can remain positive for 15 to 18 years and get protection from getting hepatitis B again. 3. Management of patients and carriers Family members of patients are tested for serum HBsAg, anti-HBc and anti-HBs, and those who are susceptible (negative for all three markers) are vaccinated against hepatitis B. The infectivity of hepatitis B patients and HBV carriers depends mainly on the level of HBV DNA in the blood, but not on serum ALT, AST or bilirubin levels. For chronic HBV infected patients and inactive HBsAg carriers, they can work and study as usual, but they should be followed up medically on a regular basis.