HBV infection is prevalent worldwide, but the intensity of HBV infection varies greatly from region to region. According to the World Health Organization, about 2 billion people worldwide have been infected with HBV, 350 million of whom are chronically infected with HBV, and about 1 million people die each year from liver failure, cirrhosis and primary hepatocellular carcinoma (HCC) caused by HBV infection. Xu Rulong, Department of Infectious Diseases, Nanchang Ninth Hospital, 2006 National Hepatitis B Epidemiologic Survey, China’s general population aged 1-59 years old, HBsAg carrier rate of 7.18%, children under 5 years old, HBsAg is only 0.96%. According to this projection, China’s existing chronic HBV infection of about 93 million people, of which about 20 million cases of chronic hepatitis B patients. HBV is a blood-borne disease, mainly transmitted through blood (e.g., unsafe injections, etc.), mother-to-child and sexual contact. Due to the implementation of strict HBsAg screening of blood donors, HBV infection caused by blood transfusion or blood products has been less frequent; transmission through broken skin and mucous membranes is mainly due to the use of non-strictly sterilized medical devices, invasive diagnostic and therapeutic operations and surgeries, and unsafe injections, especially drug injections, etc.; other factors such as pedicures, tattoos, pierced earrings, accidental exposures to medical personnel in the course of their work, and the use of razors and toothbrushes can also be transmitted (Ⅲ). Others, such as foot tattoos, earring piercing, accidental exposure of medical personnel at work, and sharing of razors and toothbrushes, can also be transmitted (III). Mother-to-child transmission mainly occurs in the perinatal period, mostly through contact with the blood and body fluids of HBV-positive mothers during labor and delivery (Ⅰ). With the application of hepatitis B vaccine combined with hepatitis B immune globulin, mother-to-child transmission has been greatly reduced. Unprotected sexual contact with an HBV-positive person, especially if the person has multiple sexual partners, increases the risk of HBV infection (I). HBV is not transmitted through the respiratory and digestive tracts, so daily study, work or living contacts such as working in the same office (including sharing computers and other office supplies), shaking hands, hugging, living in the same dormitory, eating in the same restaurant and sharing toilets, which do not involve exposure to blood, are generally not contagious with HBV. Epidemiological and experimental studies have not found that HBV can be transmitted by blood-sucking insects (mosquitoes, bedbugs, etc.).