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Updated: Jun 29, 2026
09:57
Development and Validation of a Quantitative PCR Method for Equid Herpesvirus-2 Diagnostics in Respiratory Fluids
Published on: March 17, 2016
New hosts for equine herpesvirus 9
Mark D Schrenzel1, Tammy A Tucker, Taryn A Donovan
1Zoological Society of San Diego, Wildlife Disease Laboratories, Escondido, California 92027, USA. mschrenzel@sandiegozoo.org
Emerging Infectious Diseases
|October 2, 2008
Summary
Equine herpesvirus 9 caused encephalitis in a polar bear, originating from Grevy's zebras. This finding expands the known hosts for this virus to include new species and orders.
Area of Science:
- Veterinary Virology
- Wildlife Disease Ecology
- Comparative Pathology
Background:
- Equine herpesvirus 9 (EHV-9) is known to cause neurological disease in various animal species.
- The natural host range and transmission dynamics of EHV-9 in wildlife are not fully understood.
Purpose of the Study:
- To identify the causative agent of progressive encephalitis in a polar bear.
- To investigate the potential sources and expand the known host range of Equine herpesvirus 9.
Main Methods:
- Viral detection and identification in affected polar bear tissues.
- Source tracing through epidemiological investigation of potential equid reservoirs.
- Comparative genomic analysis to confirm viral identity.
Main Results:
- Equine herpesvirus 9 was identified as the cause of encephalitis in the polar bear.
- The virus was traced to Grevy's zebras, indicating a potential reservoir species.
- EHV-9 was also detected in an aborted Persian onager, further extending the host spectrum.
Conclusions:
- The natural host range of Equine herpesvirus 9 is expanded to at least six species across three mammalian orders.
- This study highlights the potential for cross-species transmission of EHV-9 from equids to other mammalian wildlife.
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