An attending veterinarian reported two confirmed cases of neurologic equine herpesvirus (also known as equine herpesvirus myeloencephalopathy or EHM) in Wheatland County, Alberta, Canada.
Ten other horses at the boarding facility were suspected of having disease and were exhibiting mild nasal discharge. Twenty horses were exposed.
There is a voluntary quarantine in place.
The first confirmed case was in a 14-year-old Paint mare that had onset of clinical signs on May 5 that included ataxia, hind limb ataxia, nystagmus and weakness of the hind limbs. She was confirmed with EHM on May 10. She was affected and alive at the time of this report.
The second horse was a 9-year-old Quarter Horse mare that had onset of clinical signs on June 2 that included ataxia in all limbs, hind limb ataxia, being unable to back up, dog sitting, stumbling, and ataxia when turning. The mare was confirmed with EHM on June 8. She was affected and alive at the time of this report.
To learn more about neurologic equine herpesvirus read this Fact Sheet.