Viral hepatitis B (Hepatitis B) is a common infectious disease of category B in China, which is one of the key infectious diseases to be prevented and treated, and is mainly transmitted through blood, mother-to-child and sexual transmission. Close daily contact with hepatitis B patients, their blood, breast milk, vaginal secretions, etc. contain hepatitis B virus, which may cause hepatitis B virus infection if it enters the body through mucous membranes or tiny abrasions and fissures in the skin. Unsafe injections (drug abuse, drug addicts, etc.) and unclean sex also pose a risk. There is an effective hepatitis B vaccine to prevent hepatitis B infection. In addition, avoiding excessive contact with infected persons, avoiding medical transmission (unregulated use of syringes, blood products, etc.), and avoiding bad sexual behavior are all effective preventive measures.