[Is endemic hepatitis E infection present in developed countries?--Accumulating information about the hepatitis E...

There are several new data on the acute viral hepatitis particularly on infectious non-A-non-C hepatitis viruses. The hepatitis E virus infection was originally thought to be limited only for certain geographic areas and humans. Recently, it has been demonstrated the genetic diversity and worldwide distribution of hepatitis E virus in human population, as well as, the circulation of the virus in many species of animals. It is evident, that hepatitis E virus can spread by fecally contaminated water (waterborne transmission), by meat of infected animals (food-borne transmission), by animal-human contact (zoonotic transmission), and even by transfusion (blood-borne transmission). The frequency of hepatitis E virus infections among the acute hepatitis cases with unknown origin is supposed to be more than 10%. In the differential diagnosis of hepatitis, possible hepatitis E virus infection must be now taken into account even in those areas and countries, like in Hungary, where the infection was previously thought to be non-endemic. To confirm the clinical diagnosis of hepatitis E virus infection, virus specific ELISA and molecular methods are now available. In the near future, a molecular epidemiological study will be organized for the detection of hepatitis E virus in Hungary in collaboration with 9 European countries.--This review covers all aspects of the hepatitis E virus infection including the characteristics and transmission of the etiological agent, the clinical symptoms, its epidemiology, laboratory diagnosis, and some possible control measures.