DETECTION OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS (EEHV) IN FREE-RANGING AFRICAN ELEPHANTS (LOXODONTA AFRICANA) IN THE KRUGER NATIONAL PARK, SOUTH AFRICA

Tanya J Kerr; Jana van Heerden; Wynand J Goosen; Léanie Kleynhans; Peter E Buss; Erin Latimer; Michele A Miller

doi:10.7589/JWD-D-22-00015

DETECTION OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS (EEHV) IN FREE-RANGING AFRICAN ELEPHANTS (LOXODONTA AFRICANA) IN THE KRUGER NATIONAL PARK, SOUTH AFRICA

J Wildl Dis. 2023 Jan 1;59(1):128-137. doi: 10.7589/JWD-D-22-00015.

Authors

Tanya J Kerr¹, Jana van Heerden¹, Wynand J Goosen¹, Léanie Kleynhans¹, Peter E Buss², Erin Latimer³, Michele A Miller¹

Affiliations

¹ Department of Science and Innovation-National Research Foundation Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, Tygerberg 7505, South Africa.
² Veterinary Wildlife Services, South African National Parks, Kruger National Park, Private Bag X402, Skukuza 1350, South Africa.
³ Elephant Herpesvirus Laboratory, Smithsonian's National Zoo and Conservation Biology Institute, 3001 Connecticut Ave. NW, Washington, DC 20008, USA.

PMID: 36584337
DOI: 10.7589/JWD-D-22-00015

Abstract

Elephant endotheliotropic herpesvirus (EEHV) infection can cause acute, often fatal, EEHV hemorrhagic disease in free-ranging and human-managed Asian elephants (Elephas maximus) and human-managed African elephants (Loxodonta africana). However, significant knowledge gaps exist pertaining to the presence of EEHV in free-ranging African elephant populations. We retrospectively screened 142 opportunistically collected samples (blood, n=98; bronchoalveolar lavage (BAL) fluid, n=21; trunk wash (TW) fluid, n=23) obtained between 2010 and 2020 from 98 free-ranging African elephants in the Kruger National Park, South Africa, for the presence of different EEHVs, as well as determining the real-time quantitative PCR positivity rate in this population. With the use of validated, previously published DNA extraction and real-time quantitative PCR protocols provided by the National Elephant Herpesvirus Laboratory (Washington, DC, USA), EEHV was detected in nine male African elephants from samples collected in 2011 (n=1), 2013 (n=1), 2018 (n=2), 2019 (n=4), and 2020 (n=1). Viral detection was more common in respiratory compared with blood samples. Six elephants tested positive for EEHV2 subtype (blood, n=2; BAL, n=3; TW, n=2), including one individual that tested positive on matched respiratory samples (BAL and TW). Four elephants tested positive for EEHV3-4-7 (blood, n=1; BAL, n=2; TW, n=1), whereas EEHV6 was not detected in any of the study animals. One elephant tested positive for both EEHV2 and EEHV3-4-7 in the same BAL sample. Even though the levels of viremia varied between 158 and 1,292 viral genome equivalents/mL blood and viral shedding of EEHV2 and EEHV3-4-7 was detected in respiratory samples, no clinical signs were observed in these apparently healthy elephants. These findings are consistent with reports of asymptomatic EEHV infection in human-managed African elephants.

Keywords: Loxodonta africana; African elephant; EEHV; Kruger National Park; elephant endotheliotropic herpesvirus.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Elephants*
Herpesviridae Infections* / epidemiology
Herpesviridae Infections* / veterinary
Herpesviridae* / genetics
Humans
Male
Parks, Recreational
Retrospective Studies
South Africa