Hepatitis E virus (HEV) belongs to the Calcivirus family. It is a polyadenylated single-strand RNA non-enveloped virus. Its epidemiology is similar to that of hepatitis A: transmission by the faecal-oral route and incidence in epidemic or sporadic form. The incubation period is 15 to 64 days. It infects young adults 15 to 40 years of age causing acute or fulminant disease. Hepatitis E infection can be fatal in pregnant women. Diagnosis depends on measuring increased aminotranferase activity and detecting specific IgG and IgM antibodies during the acute phase of the disease (the jaundice). Anti-HEV specific IgG antibodies persist for about one year.