The Canadian Animal Health Surveillance System has confirmed that two horses have been identified with a neurological form of the Equine Herpesvirus in a barn in the Saint-Lazare region of Montérégi, QC. A vaccinated horse is severely affected and must be eaten; The other animal has been quarantined. The recent introduction of a new horse into a stable without prior quarantine is one of the risk factors for this outbreak.
The equine herpesvirus type 1 is highly contagious and can manifest in respiratory, neurological, and abortive disorders. Horses can shed the virus and infect other horses without showing obvious signs of illness. A sick horse that has developed symptoms is usually still contagious for 1 to 2 weeks (up to 21 days) after they disappear.
The symptoms of the neurological form of the disease and the degree of infection can vary between horses and can be manifested by fever, decreased appetite, depression, mild to severe loss of coordination ( often more evident in the hind limbs), urinary incontinence, caudal atony, etc. Sometimes death is necessary in severely affected horses. This depends on various factors, including the presence of a highly pathogenic strain of the virus.
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