Hepatitis B check more than twenty years ago, husband and children are not infected usually due to the hepatitis B virus is less contagious or husband and children have hepatitis B antibodies and other cases. 1. small contagious: hepatitis B virus contagious mainly depends on the replication of the virus, if the virus replication is active, the contagiousness is relatively large, and vice versa, the contagiousness is relatively weak, if the hepatitis B virus in the body is in the replication of the inactive state, then the husband and the child may not be infected. 2. Hepatitis B antibody: If the husband and children already have hepatitis B antibody, then even if they have hepatitis B their chances of being infected will be very low. Because hepatitis B is a contagious disease, in order to reduce the risk of family members getting infected, it is recommended that the whole family have regular medical checkups.