Detection of HEV-specific antibodies in four non-human primate species, including great apes, from different zoos in Germany

Abstract

The hepatitis E virus (HEV) has been described in humans and various animal species in different regions of the world. However, the knowledge on natural HEV infection in non-human primates and the corresponding risk of zoonotic transmission is scarce. To determine whether primates in captivity are affected by HEV infection, we investigated 259 individual sera of clinically healthy non-human primates of 14 species from nine German zoos. Using a commercial double-antigen-sandwich ELISA and a commercial IgG ELISA, 10 animals (3·9%) reacted positive in at least one assay. Three ape species and one Old World monkey species were among the seropositive animals: bonobo (Pan paniscus), gorilla (Gorilla gorilla gorilla), lar gibbon (Hylobates lar) and drill (Mandrillus leucophaeus). Testing for anti-HEV-IgM antibodies by commercial ELISA and for viral RNA by reverse-transcription real-time polymerase chain reaction resulted in negative results for all animals indicating the absence of acute HEV infections. In the past, no clinical signs of hepatitis were recorded for the seropositive animals. The results suggest that non-human primates in zoos can get naturally and subclinically infected with HEV or related hepeviruses. Future studies should evaluate potential sources and transmission routes of these infections and their impact on human health.

Survey for Hepatitis E virus infection in non‐human primates in zoos in Spain

“…Five of the 33 species tested presented at least one animal with anti‐HEV antibodies. The seropositivity detected in our study (4.4%) was in accordance with that found in NHPs in zoos in Italy (4.6%; 4/86) and Germany (3.9%; 10/259) (Melegari et al, ; Spahr, Knauf‐Witzens, Dähnert, et al, ). In contrast, previous studies failed to detect anti‐HEV antibodies in NHPs in zoos from China (0/2) and Korea (0/1) (Song et al, ; Zhang et al, ).…”

“…Additionally, since there is a direct relationship between volume of food ingested and size of animal, the probability of HEV infection could also be proportionally higher. Ingestion of contaminated water or meat products is considered the main route of HEV transmission in humans (Pavio et al, ) and probably also in NHPs (Spahr, Knauf‐Witzens, Dähnert, et al, ). However, since the diet of these species is mainly herbivore and the virus has also been detected in fruit and vegetables (Kokkinos et al, ; Terio et al, ), they should be considered possible sources of infection.…”

“…In this context, the seroconversion detected in one chimpanzee confirms HEV circulation in zoo C between 2015 and 2016. Even though biosecurity measures are implemented in the facilities housing NHPs in the zoos sampled in this study, the transmission of HEV by direct or indirect contact with other NHPs, humans, or other sympatric species, such as wild rats and cats, cannot be ruled out (Huang et al, ; Spahr, Knauf‐Witzens, Dähnert, et al, ; Zhang et al, ). In this context, natural infection and transmission of HEV among NHPs housed together in the same facilities have been evidenced previously (Yamamoto et al, ).…”

“…Non‐human primates (NHPs) have been widely used as models in HEV studies, confirming their susceptibility to HEV infection by genotypes 1–4 (Reviewed in Spahr, Knauf‐Witzens, Vahlenkamp, et al, ; Kenney & Meng, ). Likewise, serological and molecular studies have evidenced natural exposure to HEV in NHPs (Hirano et al, ; Melegari et al, ; Spahr, Knauf‐Witzens, Dähnert, et al, ; Spahr, Knauf‐Witzens, Vahlenkamp, et al, ). Nevertheless, information on the role of these species in the epidemiology of HEV is still very limited.…”

Detection of hepatitis E virus antibodies among Cercopithecidae and Hominidae monkeys in Cameroon

“…A previous study also showed the presence of anti-HEV IgG antibodies among gorilla and drill in Germany. 11 Some studies have shown the presence of anti-HEV IgG antibodies in other species of non-human primates, including the Japanese monkeys, rhesus monkeys, cynomolgus monkeys, Taiwanese monkey and white-naped mangabey. 9,10,12 Meanwhile three NHP in this study had IgM markers indicative of recent HEV infection, that is, chimpanzee, olive baboon and agile mangabey.…”