Hepatitis B is a common infectious disease in Hong Kong. It is mainly transmitted vertically from an infected mother to her new born baby and can also be transmitted through infected blood or body fluids gaining entry into a person's body, such as sharing a needle and syringe among intravenous drug abusers, ear piercing, tattoo or through unprotected sexual intercourse.
In Hong Kong, about 8% of the population are chronic Hepatitis B virus carriers. Although they are infected, most of them show no symptoms of the disease. About one quarter of these carriers will subsequently develop chronic hepatitis, and they are more prone to develop cirrhosis of liver or liver cancer. For people who have never been infected, it is advisable to receive Hepatitis B vaccination to ensure immunity. Blood tested positive for Hepatitis B surface antigen and/or nucleic acid will be discarded and the donor will be informed of the test result and advised not to donate again.