Hepatitis E virus in humans, farm animals and animals from the sylvatic environment

Hepatitis E virus (HEV) is a hepatovirus causing infections in humans and in many animal species. According to the current knowledge, HEV strains have been classified in the genus Orthohepevirus, family Hepeviridae, which encompasses strains belonging to one of seven virus genotypes. Genotypes 1 and 2 have only been found in humans, while genotypes 3 and 4 have been detected in humans, pigs, deer, rabbits and mongoose. The other HEY genotypes infect wild animals. However, the full spectrum of animal species being the natural reservoir of HEV has not been fully recognized. The clinical course of hepatitis in animals is asymptomatic, and infections do not cause significant losses in animal farming. Unlike in animals, infections in humans, and especially in pregnant women, can cause serious health problems. The identification of new virus strains in the animal reservoir and the possibility of transmission of some animal HEV strains to humans make the issue of public health protection and food safety even more important. This article provides an overview of data on the prevalence of HEV infections in animals and their impact on human and animal health.