07/31/2025
When is the last time you had a frank conversation during which you listened to your VETERINARIAN guide your decision making process to appropriately vaccinate for your horses? Not the person at the grain store, not Dr. Google, not an online forum, but your VETERINARIAN?
Every year we see cases of preventable diseases in horses who were either not vaccinated or not properly vaccinated.
The RABIES vaccine is almost 100% effective and rabies is a fatal zoonotic disease. Horses vaccinated against the WEST NILE VIRUS are more than thirty times less likely to contract disease than unvaccinated horses yet many unvaccinated horses unnecessarily die from it every year. The TETANUS vaccine is almost 100% effective, and you guessed it – we see horses die of tetanus sadly, simply because they were not properly vaccinated.
Here’s the skinny on equine vaccines:
1. CORE VACCINES: EVERY horse in the United States has the same risk of most diseases REGARDLESS of their potential contact with other horses & should be vaccinated annually with against:
a. Encephalitis: Spread via infected mosquitoes from the wild bird population & not spread horse to horse
i. West Nile Virus
ii. Eastern Equine Encephalitis
iii. Western Equine Encephalitis
b. Tetanus – in the environment & horses are very susceptible
c. Rabies – spread by contact with saliva of infected animals, common wild hosts: raccoon, skunk, bat, fox, etc
2. RISK BASED VACCINES: Communicable / Infectious diseases for which we vaccinate: diseases spread between horses
a. Influenza: every 6 months
b. Herpes (EHV1 & EHV4): every 6 months
i. NOTE: there is no effective vaccine against the neurologic form
c. Strangles: annually and only in high risk scenarios
3. ADDITIONAL RISK BASED VACCINES:
a. Potomac Horse Fever – contracted by consuming may flies (caddis flies) typically in water sources & common in our area
i. We recommend the Potomac horse fever vaccine as a core vaccine twice a year in our region
b. Botulism – associated with decay (greater significance when feeding round bales & silage)
i. we recommend botulism as part of the pre-foaling vaccination protocol for all broodmares
ii. we recommend botulism as part the annual vaccine protocol for all horses eating round bales
iii. we strongly encourage owners to vaccinate against botulism as we are in a regions with a high botulism risk
4. Pregnant Broodmares
a. EHV-1: months 3, 5, 7, 9
i. To prevent EHV-1 associated abortion
b. Rotavirus: months 8, 9, 10
i. Recommended for farms with a history of rotavirus diarrhea
c. Clostridium: 6 & 3 weeks pre-foaling
i. Recommended for farms with a history of clostridial foal diarrhea
d. All annual vaccines including botulism: month 10
5. Old horses need vaccinations just as routinely as young horses and perhaps in some cases more frequently
6. Foals should begin being vaccinated no sooner than 4 months of age and closer to 6 months to avoid the interference of maternal antibodies and for their immune system to be appropriately developed to make antibodies
7. Unvaccinated horses require boosters of all vaccines at 3-4 weeks following the initial dose
a. Botulism requires two subsequent boosters following the initial vaccination
NOTE: areas of the country have varying risk for the encephalitities and may recommend increased vaccine frequency.
Second NOTE: This is by no means a comprehensive plan for vaccinating every horse. A plan unique to your horse and your region should be made with your VETERINARIAN.
Please, please, please talk to your equine veterinarian and make a plan to keep your horses safe from preventable diseases. Their lives may depend on it.
