For chronic viral hepatitis B, the main routes of transmission are blood transmission, sexual transmission, and vertical transmission; the hepatitis B virus is not transmitted within saliva. Whether the patient is infectious or not also depends on whether the patient’s virus is replicating, i.e. whether the patient’s blood test for hepatitis B triple system is a major triple-positive or minor triple-positive situation. In the case of small triplets, there is no replication of the virus and the patient can continue to observe. In the case of major triple-positive, the patient will have hepatitis B DNA and liver function drawn, if it indicates that the hepatitis B DNA virus has replicated and combined with liver function damage. At this point, the patient is considered to be in the window phase of viral replication, and antiviral treatment can be actively considered. Patients have a certain degree of contagiousness, and their blood and body fluids are likely to carry hepatitis B virus, so they should be properly isolated. If there is a family member with chronic viral hepatitis B, the toothbrush, razor and utensils used daily should be properly isolated to avoid transmitting the hepatitis B virus to the family. If a normal member of the family has an open wound, contact with the patient’s blood should be avoided so that he/she will not be infected with chronic viral hepatitis B.