Once known as enterically transmitted non-A, non-B hepatitis, hepatitis E virus (HEV) is the sole member of the family Hepeviridae, genus Hepevirus . First isolated and distinguished from hepatitis A virus in 1980, HEV was classified in the Caliciviridae family from 1988 to 1998 and then the unassigned genus Hepatitis E-like viruses (Wang and Zhuang 2157).