[How to investigate and diagnose autochthonous hepatitis E?].

In developed countries, HEV infection was still recently considered as rare, and as an imported disease from endemic areas by travellers. Hepatitis E virus is now recognized mainly as an autochthonous disease in these countries. Although the source and the route of contamination remain uncertain, several cases of food-borne (zoonotic transmission) and blood-borne transmission have been recently reported. The mortality rates in industrialized countries seems to be higher than in endemic areas, since the infection occurs more frequently in elderly people with underlying chronic liver disease (mortality rate approaching 70% in this subgroup of patients). By contrast, whereas mortality rate rises by 20% during pregnancy in developing countries, no death in pregnant woman from developed countries secondary to an autochthonous case has been reported so far. Lastly, HEV infection may be a cause of chronic hepatitis in immunocompromised patients (mostly in solid organ-transplant recipients) which can evolve to cirrhosis.