Prevalence of hepatitis E virus infection in Thailand

Hepatitis E, also known as epidemic, non-A, non-B hepatitis, is an acute, enteric, infectious disease. The disease is usually mild, except in pregnant women, who suffer a high fatality rate from fulminant hepatic failure. Information on the disease in Thailand is limited. The prevalence of antibodies to the aetiological agent, hepatitis E virus (HEV), was therefore studied, in various groups of subjects from several regions of this country, using commercial ELISA for anti-HEV IgG and IgM. The prevalence of anti-HEV IgG, which was 9%-22% in the adult subjects (blood donors, pregnant women, patients with acute hepatitis and cases seen during an outbreak of hepatitis), increased with age. It was relatively low in children and adolescents from Bangkok (3.6%) and in children from the north-east (1.8%-6.2%) and south (2.3%) of the country. Five (7%) of the 68 patients with acute viral hepatitis who were tested for anti-HEV IgM were found positive. Although these five cases had jaundice (four cases), diarrhoea (three) and/or dark urine (at least four cases), all of these clinical signs were self-limiting and had no sequelae. Given the apparently high prevalence of HEV infection in young adults in Thailand, control measures, including provision of clean water supplies and better personal sanitation and food hygiene, should be implemented to prevent an epidemic of the disease.