Routine vaccinations are a vital part of caring for your horse

Just as vaccines protect the health of people, they also help minimize the risk and severity of disease in horses. Across Ontario, the diseases we most commonly vaccinate against for horses are:
Highly recommended for all horses


A fatal neurological virus that is exceedingly well controlled with routine vaccination.


Horses are particularly prone to tetanus for two main reasons: they suffer a lot of wounds, and the tetanus bacteria is commonly found in horse feces. Tetanus is generally fatal for horses, whereas vaccination is extremely effective at preventing tetanus from developing. Failure to vaccinate for tetanus could reasonably be viewed as abusive management.


Eastern and Western Encephalitis Virus (EEE/WEE) and West Nile Virus (WNV): Infected horses show a range of symptoms, including lack of muscle control, weakness of the limbs, the need to lean on supports or lie down, muscle tremors and fever. Cases are most likely to appear in late summer and early fall. In addition to vaccination, mosquito population control is also very important. Be sure to eliminate any standing water on your property!

Recommendation dependent on lifestyle of the horse (showing, travelling, boarding, etc.)


A contagious virus that frequently circulates at horse shows, the flu principally affects the upper respiratory tract. Infection results in respiratory disease, setbacks in training and potentially more serious complications such as pneumonia and pleuritis. Please note that many secondary complications may be a result of horses returning to work too soon. Affected horses should be rested for at least as many weeks as the number of days they were clinically ill. Unfortunately, the immunity generated in response to influenza vaccines is short-lived. For this reason, we usually recommend an initial dose be administered just ahead of show season, with additional doses given every 3 months to boost protection throughout the risk period.


There are many strains of the Herpes virus in horses. The main forms of the virus cause poor performance and respiratory disease, abortion in pregnant mares and, in some cases, neurological disease. Vaccination together with good hygiene and biosecurity practices are essential to control for all forms of this disease.


This highly contagious bacterial disease spreads rapidly, particularly among large groups of stressed horses. A positive strangles case in a show barn could result in the quarantine of all horses on the property. The quarantine would remain in effect until you can demonstrate that none of the horses is shedding the bacteria. A strangles outbreak is definitely not something you want to risk in the middle of show season!


We believe our Equine Wellness and Preventative Care Program, combined with good nutrition and regular exercise, will help keep your horse healthy, happy and full of competitive spirit. Let us assist you in determining the best healthcare plan for your horse.

Learn more about:


Allossery Equine Veterinary Services
11499 York Durham Line
Mount Albert, Ontario
L0G 1M0

(289) 338-2068