Hepatitis B: global importance and need for control.

Hepatitis B is a disease of global importance, with greater than 300 million carriers of the virus world-wide. Hepatitis B virus (HBV) is the cause of up to 80% of cases of primary liver cancer, the single most important cause of mortality globally. In countries where HBV carrier rates reach 10%, HBV infection may account for 3% of total mortality, a level which exceeds polio-related mortality before the introduction of polio vaccine. The only means by which hepatitis B can be eventually eliminated is mass vaccination of infants with hepatitis B vaccine as part of the Expanded Programme on Immunization (EPI) in areas of the world where the HBV carrier rate exceeds 2.5%. With recent dramatic increases in hepatitis B vaccine production and decreases in per-dose price, there are grounds for optimism that global HBV infection rates may be reduced by as much as 90% over the next 10 years.