Viral hepatitis E. Current knowledge and future problems

: Hepatitis E is the principal enterically-transmitted non-A, non-B, non-C hepatitis, responsible for large epidemics of acute hepatitis associated with fecal contamination of drinking water in under-developed and developing countries. In contrast, in the industrialized world, the infection occurs rarely and sporadically, usually in individuals who originated from or traveled to regions of known endemism. However, serological and virological studies have provided evidence that hepatitis E virus may be circulating in geographical areas not previously considered to be endemic. Hepatitis E is a self-limiting, acute disease with an overall mortality rate of 0.4-4%, although a more severe course has been observed in pregnant women, in whom mortality can rise to 20%. Enzyme immunoassays and polymerase chain reaction are available for definitive diagnosis. The immune serum globulins have not evidenced certain beneficial effects during hepatitis E epidemics, and candidate vaccines have not yet reached the clinical trial stage.