Reduction of infectivity in chronic hepatitis B virus carriers among healthcare providers and pregnant women by antiviral therapy.

The main purpose of therapy for infectious diseases is restoration or protection of the patient's health, but suppression or elimination of infectious agents is also important. In two well-defined situations, reduction of potential infectivity may be the main reason for therapy in hepatitis B virus (HBV) carriers who do not suffer from significant disease: (1) healthcare providers who perform exposure-prone procedures to prevent transmission of HBV to individuals, and (2) pregnant women in the third trimester to prevent transmission to the fetus. This article describes the necessity to recognize highly viremic HBV-infected individuals in these situations, the methods to estimate the risk of transmission, and the therapeutic possibilities to prevent transmission. With today's methods of monitoring HBV DNA, it is possible to reliably estimate the risk of transmission. The drugs entecavir or tenofovir are able to suppress infectivity of HBV carriers to levels acceptable for healthcare providers performing exposure-prone procedures. According to the CDC, 'chronic HBV infection in itself should not preclude the practice or study of medicine, surgery, dentistry, or allied health professions.' Treatment of pregnant women with very high levels of HBV DNA prevents the transmission to the fetus and further if the newborn receives immediate active/passive immunization against HBV.