During an outbreak of equine herpes virus 1 (EHV-1) in a zoological institution, one Thomson´s gazelle (Eudorcas thomsoni) died acutely with neurologic signs, whereas a second individual showed neurologic signs progressing to stupor which allowed supportive therapy along with intramuscular florfenicol (Nuflor, Essex Tierarznei, München, Germany), flunixin-meglumine (Finadyne RP, Essex Tierarznei, München, Germany), and oral famciclovir (Famvir, Novartis, Barbera del Valles, Spain). During the following three days, three to six animals of a colony of guinea pigs which were housed in an adjacent room to the hoofstock area, were found dead each day. The second Thomson’s gazelle and remaining guinea pigs were euthanatized due to high risk of infection and poor prognosis. Meningoencephalitis due to EHV-1 was diagnosed in all affected animals.
This is the first report of EHV-1 in caviidae but equine herpes viruses have been described to cause fatal infections in a range of non-equid species.1,2,4,6,7 Thomson´s gazelles appear to be a particularly susceptible unnatural host.3,5,8 Equid species were assumed the reservoir and the proximity of the susceptible species to equids is considered critical. The described Thomson’s gazelles were housed in a multispecies exhibit with other hoofstock, including zebras (Equus quagga boehmi).
After the outbreak, a serologic survey of all species kept in proximity with equid species was conducted. Unfortunately, there was disagreement in the results from different laboratories on the same samples but there was clear evidence for seropositivity in the equids. Vaccination protocols were introduced to prevent further outbreaks.
The authors would like to thank Dr. Prof. B. Grummer and Dr. Prof. L. Haas from the Institute of Virology at the University of Veterinary Medicine in Hannover, Germany, for characterizing the equine herpes virus.
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