Page 31 - New Mexico Summer 2021

Risk-based vaccinations are based on a risk-benefit analysis of the lifestyle of your horse. The use of these vaccines vary from region to region and from population to population within a given
area. Risk-based vaccinations include those for Equine Viral Arteritis, Equine Influenza, Equine Herpesvirus/Rhinopneumonitis, and Strangles.
or human to human. Like EEE/WEE, vaccination is recommended in the spring prior to vector season. When I first moved to New Mexico from east Texas, I figured there would be a much lower incidence of WNV
in the arid part of the state I was residing... wrong! Because of all the irrigating that takes place, mosquitoes are still a real threat.
Tetanus: unlike the first 2 disease
groups mentioned, tetanus is not caused by
a virus. Tetanus is caused by a soil borne bacteria: Clostridium tetani. All horses are at risk of tetanus, and it is often fatal in unvaccinated horses. Horses are significantly more susceptible to these bacteria than people, which is why we get a tetanus shot every 10 years or so, but your horse will receive a booster if they sustain a laceration, puncture, or have surgery 6 months or more post vaccination. It is common for tetanus toxoid to be included in our combo vaccines, so frequently owners do not realize their horse has in fact been vaccinated for tetanus. Tetanus is the “T” in the frequently used “EWT” or ”VEWT” vaccine. There is also an available tetanus toxoid vaccine that is usually given when a booster is required following a laceration, etc.
Rabies: this viral disease is 100% fatal
if contracted. The good news, however, is that it is 100% preventable with vaccination. Rabies is the disease on the core vaccination list with the greatest risk to horses and people alike and is a tremendous public health concern. Rabies, unlike the other diseases mentioned, is transmissible from horse to horse and horse to human. We
don’t think twice about providing a rabies vaccine to our dogs (because it is state
law) and everyone has seen Ole Yeller
and knows what a rabid dog looks like. But rabid horses often present differently with vague, even mild, neurologic symptoms
that then progress to manic and more severe and dangerous neurologic symptoms. In
the period before a horse progresses to the severe stages of the disease many people
can potentially be exposed, thus creating a public health nightmare. While, thankfully, incidence of rabies in horses is low, many people do not realize that their horse is still at risk of contracting this terrible disease.
Risk-Based Vaccination Diseases
Risk-based vaccinations for diseases such as influenza and equine herpesvirus (or rhinopneumonitis, aka rhino) are common practices in our racing and breeding populations as these upper respiratory diseases often spread quickly through a barn. While they have a high morbidity, meaning lots of horses get sick, they are typically low mortality (not many will die). But as we
in New Mexico know all too well, equine herpesvirus doesn’t always play nice and
stay a simple upper respiratory infection. Aside from the terrible neurologic condition Equine Herpesvirus Myeloencepahlopathy (EHM) that can occur, EHV also causes abortion in pregnant mares. So, while your young racehorse might just get the snots and run a fever and feel crummy, your exposed
pregnant mare could suffer an abortion. Worse even, you could end up dealing with what is referred to as an abortion storm, or abortion outbreak, where many mares abort in a short period of time.
Planning a vaccination protocol for your horse herd can seem a daunting task, but addressing the needs of each class of horse
in your population (racehorse, broodmare, weanling, yearling, stallion) can help simplify the process. Deciding which vaccine to use, and when to use it, is a plan you should make with your veterinarian. While some vaccines are available through your local feed store or supply store, understand that most vaccine manufacturers will stand by their product when administered by a veterinarian and in many cases will provide treatment in the event of a vaccine failure (this depends on the individual vaccine
and company). While the core vaccination requirements will remain the same, differing series of vaccines may be required based on the classification of horse you are dealing with. Understanding the diseases being targeted and why it is important to provide protection to our equine companions in the form of vaccination makes it easier as well. As the saying goes, an ounce of prevention
is worth a pound of cure. Vaccination is a simple way to help improve the overall health and well-being of our horses.
Planning a vaccination protocol for your horse herd can seem a daunting task but addressing the needs of each class of horse can help simplify the process.
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