11/19/2025
There have been a number of confirmed cases of EHV/EHM lately, both in Canada and the USA. So here’s what you need to know about the disease 🚨
Equine Herpesvirus is a common virus in horse populations worldwide. The most common species are EHV-1, which causes respiratory infections, abortion and can cause neurological disease (EHM), and EHV-4, which most commonly causes respiratory disease.
The disease is highly contagious and gets spread through nasal secretions, both through direct (nose to nose contact) and indirect (through equipment, people,…) contact.
When infected, most horses will develop a fever, become lethargic, go off feed and water. If the disease progresses, respiratory signs (like coughing and nasal discharge) and neurological signs (ataxia, trouble swallowing, loss of tail tone, weakness in the hind end,…) can become apparent.
As this is a viral infection, no specific treatment is available. Treatment of the disease is therefore largely focused on supportive care (IV fluids, anti-inflammatories,…).
This is why prevention is so important!!!
There are things you can do to help control the spread and help protect your horse.
We recommend vaccinating against EHV, especially if your horse is frequently in contact with other horses.
Practice strict biosecurity when visiting with your horse at the barn and when travelling. Avoid contact with other horses, use your own food and water bucket, don’t share grooming supplies, etc.
Herpes vaccines cover for type 1 and type 4, but the vaccine is made for respiratory and abortion form of the disease. There is not a vaccine made for the neurological/meningitis form, which is what our biggest concern is today.
If you have questions regarding the disease, or you suspect your horse may be affected, please do not hesitate to reach out to us via phone (780-922-3647) or email ([email protected])
The AAEP also has some great resources for owners at aaep.org/resource/ehv-faq-for-owners/
