(1) blocking mother-to-child transmission: the mother is a HBsAg-positive newborn. Intramuscular injection of hepatitis B immunoglobulin must be given within 48 hours after birth (the earlier the better), and once every 1 month, and then combined with hepatitis B vaccine, the protection rate for the baby can reach 70% ~ 90%.
(2) Prevention of hepatitis B virus infection under special circumstances: When people susceptible to hepatitis B accidentally encounter the risk of hepatitis B virus infection on some occasions, they can use hepatitis B immunoglobulin alone. For example, when doctors, nurses and inspectors accidentally stab their fingers with a needle tip or cut their fingers with a scalpel in the process of treating, nursing or drawing blood to detect carriers of hepatitis B surface antigen, the blood of patients with hepatitis B virus can enter the above-mentioned people through skin trauma. In this case, the infected person should immediately (within 12 hours) inject 1 hepatitis B immunoglobulin, and then inject again after 1 month to prevent infection.