Viral hepatitis B, or hepatitis B, is an infectious disease caused by the hepatitis B virus that mainly damages the liver. Hepatitis B is mainly transmitted through contact with the blood and body fluids (semen and vaginal fluids) of infected persons. 2, sexual contact transmission: unprotected sexual intercourse, homosexual sexual contact. 3, close contact transmission: blood, semen, vaginal secretions, breast milk of hepatitis B patients or carriers may contain hepatitis B virus, which is contagious and can contaminate utensils and objects. Young children may be infected through scratching and biting; using contaminated objects in daily life such as razors, nail clippers, and intravenous drug injection (sharing needles with others) may also be infected with hepatitis B. 4. Blood-borne transmission: Receiving blood or blood products contaminated by hepatitis B virus. In developed countries or regions, blood donors are screened for the hepatitis virus, so the likelihood of contracting hepatitis through receiving blood in these regions is extremely low. 5. Medical transmission: If medical devices are contaminated with hepatitis B virus and not sterilized or not handled properly can cause transmission, such as dental and other medical procedures, cosmetic surgery (tattoos, piercings), etc. The infection rate through sharing needles with hepatitis B patients is 30%.