Close this search box.

Equine “Core” Vaccines – An Equine Veterinarian Truck Dashboard Perspective

Equine “Core” vaccines- Tetanus, Eastern (EEE) and Western Encephalomyelitis (WEE), West Nile and Rabies. You can educate yourself on the importance of protection from these diseases from your veterinarian, on websites, textbooks and magazines. But what does the decision to vaccinate to protect your horses from these diseases mean to you, your horses and your veterinarian?



I allude to the “dashboard” in the title, as that will be my view on this hot Friday evening of the long weekend in August after another full and busy day of veterinary practice. Despite being on call, I am still hoping to join my family for a cookout at the beach. Sadly, this is not how the lovely summer evening will unfold for me, my clients or their horse.

The emergency call comes through; a valued family horse that suddenly seems to be seizuring, drooling, unable to stay standing and is uncontrollable. A frustrating drive to the farm is next- the highway is slow with rented motorhomes, SUVs with kayaks on top, plenty of pickups with boats. It seems everyone is headed off for a great weekend, and I am fighting traffic to get to a horse in serious trouble.

I arrive at the farm, and assessing the patient for TPR (temperature, pulse, respiration) is a nonstarter, as the patient is frantically trying to gain his feet and dripping with sweat in the heat. After crashing through a couple of fences, and with the help of a firefighter neighbour, we finally manage to get the patient sedated/anesthetized while we develop a treatment plan.

Question number one- vaccination status? The horse’s owners in this case are skeptical of vaccines- they have only consented to annual Tetanus vaccine. Could this be Rabies-zoonosis number one? West Nile? Eastern/Western Encephalomyelitis? Without vaccination for Rabies -who has been exposed? As the medications wear off, the neurologic symptoms return.

Transportation for hospitalization, more advanced diagnostics and supportive care is not a reasonable option in this rather remote location, especially given the dangerous state of the patient. Euthanasia is sadly the only humane and practical choice.

Post mortem diagnostics are recommended, given the potential of zoonotic disease and for disease surveillance for the rest of the herd and neighbouring farms. Human exposure for Rabies is a significant concern- several people attended to the seizuring horse. But like so many places in Canada, the nearest diagnostic laboratory for full post mortem is a day’s drive away, and it is a weekend. Now what? Remove the head for testing at a Rabies testing facility which is an entire province away? In the summer? On a weekend? And I have to convince the client to allow this?

Fast backward to the conversation we had last spring, when I explained the importance of core vaccinations and I was questioned whether vaccination for these diseases is “truly necessary”. If we could have foreseen this day, the decision whether or not to vaccinate would likely have been different.

Horse owners, please consider routine vaccination for core diseases. The annual cost far outweighs the potential animal suffering, risk of zoonotic disease exposure and the cost of emergency veterinary care. These kinds of situations are almost 100% preventable with low reaction rate vaccines. In addition, most vaccine companies now also provide an immunization guarantee, so if your vaccinated horse gets an infectious illness, they may be able to provide you with diagnostic and treatment support.

We have the means at our fingertips, we just need to get better about herd immunity!

Equine Core Vaccine Diseases- some not so “Fun Facts”

  • Core Vaccines provide protection from diseases that have the potential for significant public health consequences, are required by law and / or rules and regulations in some cases, are highly infectious and pose the risk of serious disease
  • Equine mortality rates for Core vaccine diseases are 100% for Rabies, 75% for Tetanus, 33% for West Nile, 90% for EEE, and 50% for WEE
  • In the US, human deaths for EEE in 2019 have increased from an average of 5-10 to 30 in 2019 so this disease seems to be on an upswing of prevalence
  • Post exposure treatment for humans exposed to a Rabid animal are in excess of $7,500 per person, and many people may be exposed to a single sick horse
  • Liability of owners regarding exposure of persons to zoonotic diseases is a developing concern

Written by Bettina G Bobsien, BSA, DVM, Diplomate ABVP [Equine],