Hepatitis E Virus Infection in Macaca Mulatta

One of the five known hepatitis viruses that can infect humans is hepatitis e virus (hev). the first documented infection that was caused by hev occurred in 1955 during an outbreak in new delhi, india (1). hev is a small nonenveloped particle that belongs to the family hepeviridae and the genus hepevirus. its single-stranded rna genome has approximately 7200 base pairs (2). by genomic sequence analysis, there are four genotypes (1- 4) and at least 24 subgenotypes (1a-1e, 2a-2b, 3a-3j, and 4a-4g) of hev in humans and other mammals (4). avian isolates of hev were initially proposed to constitute the fifth genotype of hev; but, due to their shorter genome and low homology with mammalian isolates, they have been categorized as a member of a separate genus (3). hev genotypes 1 and 2 are limited to humans, and genotypes 3 and 4 are common between humans and other mammalian species (5).