Pathogenicity of a New Neurotropic Equine Herpesvirus 9 (Gazelle Herpesvirus 1) in Horses

Abstract

Pathogenicity of equine herpesvirus 9 (EHV-9), a new type of equine herpesvirus isolated from Gazella thomsoni, in horses was investigated by intranasal inoculation of EHV-9 (10⁷ pfu) to two conventionally reared 8-months old half-bred weanling horses. Fever higher than 39°C was recorded. Virus was recovered from nasal swabs and peripheral blood mononuclear cells. Both horses developed neutralizing antibody to EHV-9. Perivascular infiltration of mononuclear cells and glial reaction were found in the olfactory and limbic systems. The results suggested that EHV-9 has a pathogenicity in horses.