Hepatitis E in India

Abstract

Hepatitis E is an enterically transmitted disease prevalent in developing countries in epidemic and sporadic forms. The waterborne epidemic of hepatitis in Delhi in 1955 was shown to be due to non-A–non-B aetiology, later confirmed as hepatitis E. Thereafter, a large number of epidemics of the disease have been reported from different parts of the country. Hepatitis E is the major cause of sporadic viral hepatitis among adults. High mortality among pregnant women, especially in the third trimester, and predilection for young adults remain the characteristic feature. However, the exact reasons remain unidentified. Hepatitis E virus (HEV) is an RNA virus belonging to a newly identified Hepeviridae family. The human HEV from India belongs to genotype-1 while pigs circulate genotype-4. So far, no zoonotic transmission is reported. The virus has been shown in water, sewage and soil samples. Faecal contamination of drinking water is the major source of HEV infection. Intrafamilial and parenteral transmissions are rare. The virus was transmitted to chimpanzees and rhesus monkeys. Highly sensitive and specific immunoassays have been developed for the detection of both IgM and IgG-anti-HEV antibodies. A clinical trial is awaited following the development of an effective recombinant protein-based vaccine. A significant reduction in hepatitis E was shown in pregnant women receiving human immunoglobulins. Several basic studies have thrown light on the role of different genes/proteins of the virus in the pathogenesis/replication of the virus.