It is only after the fourth dose of hepatitis B vaccine that you have 33.8 mIU/ml of antibodies, and you do not need a fifth dose of hepatitis B vaccine for the time being. Routine hepatitis B vaccine requires three injections, and the vaccination program is 0-1-6 months. 95% of healthy children and young people can produce sufficient hepatitis B surface antibodies after three doses of hepatitis B vaccine, but the level of antibody expression decreases gradually with the passage of vaccination time. According to the Technical Guidelines for Hepatitis B Immunoprophylaxis for Chinese Adults (2012), if the surface antibody against hepatitis B is <10mIU/ml or all the two halves of hepatitis B are negative, it is necessary to receive hepatitis B booster vaccination, and if the surface antibody against hepatitis B is 10~99mIU/ml or only the surface antibody against hepatitis B in the two halves of hepatitis B is weakly positive, and all the others are negative, it is generally not necessary to receive hepatitis B booster vaccination. Those who are negative in both half pairs of Hepatitis B, generally do not need booster shots. Therefore, those who have received hepatitis B booster vaccination and have hepatitis B surface antibody of 33.8mIU/ml can effectively protect against hepatitis B infection, and it is generally believed that the expression of antibody can be maintained for more than ten years, so there is no need to receive hepatitis B vaccine for a short period of time. Hepatitis B vaccine is an effective means of protection against hepatitis B infection, and in the case of high-risk groups such as immunocompromised or healthcare workers, regular monitoring of hepatitis B markers and other indicators.