The Spring Vaccines Your Horse Needs

Is your horse up-to-date on the vaccines he needs to stay healthy through the year? Protect him from seven core diseases and learn what else he might need. 

By Luke Bass, DVM, With Kaycie Timm

female veterinarian administers a vaccine
Protect your horse from harmful illness that could keep him out of the show pen by vaccinating against seven major diseases this spring. (Photo by Shelley Paulson)

When you’re prepping for a horse show, you likely have a mental or paper checklist of everything you need. Hay, feed, tack, buckets, blankets—the list goes on and on. Before you start ticking off those items, though, there’s a more important list you need to evaluate: spring vaccinations. When your horse is transported and shown, both of which induce stress and expose him to potential illness, it’s important to provide immune protection to keep him at his best. Vaccinating prior to show season allows you to maximize your horse’s performance so he can compete at the peak of his ability.

Core Protection

Start by arming your horse to combat the five core diseases for which the equine veterinary population suggests annual vaccinations. Those are:

  1. West Nile Virus
  2. Tetanus
  3. Rabies
  4. Eastern Equine Encephalomyelitis (EEE)
  5. Western Equine Encephalomyelitis (WEE)

These five annual vaccines can be given in early spring if you live in a warmer climate, but in colder areas, it’s best to wait until April or May. However, if your show season kicks off early in the year, aim to vaccinate about two weeks before potential exposure (your first show of the year). That will give your horse time to develop an immune response to fight off diseases and recover from any potential reactions to the vaccines. 

Visit to learn more about these five core vaccines and how they protect your horse from disease.

Additional Defense

For a show horse, your veterinarian will likely recommend adding two more vaccines: influenza and EHV-1. Unlike the five core vaccines, these two need to be administered every six months, or as often as every three months if your horse is on the road frequently. The same two-week rule goes for those boosters—vaccinate at least two weeks before a show to maximize protection and give your horse time to get back to normal. Keep in mind, the vaccination for EHV-1, equine herpesvirus, protects against the respiratory form of the disease, not the neurologic strain. There isn’t a vaccine to protect against the neurologic form of herpes, but preventing the respiratory form with EHV-1 is still very important. 

You might also need to consider the strangles vaccine. Although there are two vaccines available that protect against this disease, they’re not as effective as the seven previously mentioned vaccines because strangles is a bacteria, not a virus. Younger horses—specifically yearlings up to 4-year-olds—are more prone to contracting strangles, because their immune system is weaker due to lack of exposure. Consult your veterinarian to determine the best strangles-control system for your horse, whether that’s a vaccine or other measures that fit your health-care program. 

Other region-specific vaccinations may be necessary, too, depending on what your horse might be exposed to where you live and compete. Consult your veterinarian to find out what diseases are prevalent in your area, taking your horse-show travel plans into account. Remember to consider any specific requirements mandated by certain facilities or show management. Some might require documentation of vaccines given within a certain date, so be sure you have what you need ahead of time to avoid problems. 

Administration Options

Your veterinarian will administer six of the seven core vaccines discussed here with an intramuscular shot. For the influenza vaccine, you can opt for an intramuscular or intranasal vaccine, depending on your horse’s needs. The intranasal option works faster, because it stimulates a different branch of the immune system. So, if you find your horse is lacking protection fewer than two weeks before you leave for a show, this option will take effect faster than an intramuscular vaccine. Additionally, if your horse is prone to react adversely to injections, using the intranasal vaccine will lessen the number of injections he receives.

Potential Reactions

Anytime your horse receives a vaccination, there’s a chance he might experience a noticeable reaction. The vaccine is intended to produce an immune response—that’s what keeps him from catching the disease if he’s exposed in the future—so an immune reaction might occur, too. The most common reaction you’ll see is swelling at the injection site. That might make it difficult for your horse to bend, which could keep him from wanting to eat or drink. Other common responses include lethargy or low-grade fever. 

Make note: Although you can buy vaccines and administer them yourself, that’s not always the best option. When a veterinarian inoculates your horse and there’s a reaction that requires treatment, the vaccine manufacturer offers insurance that can cover some veterinary costs related to the vaccine reaction. If you self-administer, your horse won’t be eligible for that coverage. 


Dr. Luke Bass graduated from Colorado State University and worked in Central California at an equine referral practice for five years before returning to CSU to head the Equine Field Service department, where he has served for the past six years. He’s board-certified in Equine Practice and certified in Equine Acupuncture.