Elephant Endotheliotropic Herpesvirus 1, 4 and 5 in China: Occurrence in Multiple Sample Types and Implications for Wild and Captive Population Surveillance

Abstract

Elephant endotheliotropic herpesviruses (EEHVs) are important causes of death in both captive and wild Asian elephants (Elephas maximus). Nothing is known about the prevalence of EEHVs in wild or domestic elephants in China. To determine if EEHVs are present in elephants in China, 126 wild elephants from three populations and 202 captive individuals from zoos (n = 155) and the Wild Elephant Valley (n = 47) were screened using semi-nested polymerase chain reaction assays with EEHV-redundant and EEHV1/4/5-specific primers. EEHV1B and EEHV4 were detected in samples from both wild (EEHV1B:8/126; EEHV4:2/126) and captive (EEHV1B:5/155; EEHV4:9/155) elephants, while EEHV1A (six cases) and EEHV5 (one case) were only present in the captive elephants from the Wild Elephant Valley. EEHV1 was detected in blood and trunk and oral swabs; EEHV4 was detected in trunk and oral swabs as well as feces; EEHV5 was found in trunk and oral swabs. No significant age or sex association with EEHV1A, EEHV1B, or EEHV5 positivity was observed. An age association with EEHV4 positivity was found, with all unweaned elephants being EEHV4 positive, but an association with the sex of the elephant was not observed. These findings represent the first documentation of EEHV presence in captive and wild elephants in China. These findings also document EEHV1B and EEHV4 shedding in feces and demonstrate the utility of fecal screening as a tool for investigating EEHV4 infection in wild populations of elephants. It is recommended that EEHV testing be included in surveillance programs for captive and wild elephants in China.

Obesity status and its relative factors of captive Asian elephants (Elephas maximus) in China based on body condition assessment

“…Nevertheless, we suggested that long-term engagement in performance might harm the mental health of elephants, leading to stereotypical behavior. Furthermore, since captive elephants in the Wild Elephant Valley were not completely isolated from local wild elephant populations, some pathogens (e.g., EEHVs) carried by captive elephants might spread during their roaming in natural forests and cause the infection of wild individuals (Yang et al 2022).…”

First fatal elephant endotheliotropic herpesvirus type 5 infection in a captive Asian elephant in Germany

“…A 20-month-old Asian elephant in the UK was euthanized after showing a rapidly progressive disease with severe oedema and haemorrhage in the internal organs [9]. One more EEHV-5 case was reported in a captive elephant in China, which was diagnosed during a prevalence survey on EEHVs in captive animals and wild-life in China [10].…”