Hepatitis B virus: Asian perspective

Abstract

Chronic hepatitis B virus (HBV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma in Asia. HBV is generally endemic in many parts of Asia. China has the largest number of chronic HBV patients worldwide (74.6 million), with hepatitis B surface antigen (HBsAg) seroprevalence in different regions of China ranging from 3.7% to 10.4%. Other Asian countries with a high HBsAg seroprevalence include Taiwan, Mongolia, Vietnam and Uzbekistan. Migratory and behavioral patterns influence HBsAg seroprevalence rates, and the impact of HBV vaccination is gradually emerging in the younger age groups. Seroprevalence of antibody to the hepatitis B core antigen (anti-HBc) is gaining epidemiological significance due to the risk of HBV reactivation during high-risk immunosuppressive therapy. HBV genotypes B and C are commonly found in East and South East Asia, while genotypes A and D are the common genotypes in South and Central Asia. Under-treatment of HBV might be common from a public health perspective, and there is currently a paucity of evidence on the epidemiological effect of nucleoside analogue therapy on HBV-related complications. Based on available prescription patterns, nucleoside analogue coverage could be improved among the elderly age groups.