Article ID: JJID.2019.129
Cynomolgus monkey is an important experimental animal for hepatitis E virus (HEV) infection. In Japan, cynomolgus monkeys are imported mainly from Asian countries for use at animal facilities and institutions. However, the status of HEV infection in cynomolgus monkeys remains unclear. A total of 187 pairs of serum and fecal samples were collected from cynomolgus monkeys (Macaca fascicularis) imported from China and Cambodia to detect anti-HEV IgG and IgM antibodies as well as HEV RNA. Based on an enzyme-linked immunosorbent assay using HEV-like particles derived from genotype 3 HEV as the antigen, 184 of 187 (98.4%) and 102 of 187 (54.5%) samples were found to be positive for anti-HEV IgG and IgM antibodies, respectively. In contrast, all 45 serum samples collected from cynomolgus monkeys bred and grown at the Tsukuba Primate Research Center, Japan, were negative for both antibodies. However, real-time quantitative reverse transcription polymerase chain reaction detected no HEV RNA in any of the 187 serum and fecal samples. These results strongly indicated that HEV infection is common in imported cynomolgus monkeys. A source of HEV-free monkeys for HEV studies is urgently needed.
