Vaccination needs depend on the individual horse, how it’s used, its age, its environment, and your geographic location. Your veterinarian can help you plan the best vaccination program for your horse, but this is a start.
| Disease | Foals | Yearlings | Adult Horses | Broodmares |
| Tetanus | 2-4 months 1st dose Repeat in 3-4 weeks | Annual | Annual | Annual + 4-6 weeks prior to foaling |
| Encephalomyelitis (EEE-WEE) | 2-4 months 1st dose Repeat in 3-4 weeks | Annual-Spring | Annual-Spring | Annual + 4-6 weeks prior to foaling |
| Influenza | 3-6 months 1st dose Repeat in 3-4 weeks Booster every 3 mo. | 3 month intervals | 3 month intervals | 6 month intervals with booster 4-6 weeks prior to foaling |
| Rhinopneumonitis (EHV-1 & EHV-4) | 2-4 months 1st dose Repeat at 2-3 month intervals | 3 month intervals | 3 month intervals | 5th, 7th, & 9th months pre-foaling |
| Rabies | 2-4 months | Annual | Annual | Annual |
| Strangles | 2-3 months | Biannual for high risk horses | Biannual for high risk horses | Biannual + 4-6 weeks pre-foaling |
| Potomac Horse Fever | 2-4 months | Biannual | Biannual | Biannual + 4-6 weeks pre-foaling |
| Botulism (Type B) | 2 weeks – 8 months | Check with Vet | Check with Vet | Series of 3 doses a month apart – final dose 2-4 weeks pre-foaling |
In many parts of the United States, horseowners also vaccinate to protect their horses from West Nile Virus.
What is West Nile Virus? Is there a vaccine for horses and should I use it?
West Nile Virus is a sometimes-fatal virus transmitted to birds, horses, and humans through infected mosquitos. Most parts of the continental United States have seen at least some occurrences of West Nile Virus infection, typically during the summer months when mosquitos are most active.
As of 2004, two vaccines are licensed for use in horses to reduce the risk of West Nile infection. They are West Nile Innovator from Fort Dodge Animal Health and Recombitek from Merial. Both vaccines have met USDA requirements for safety testing. Although the vaccines have not been proven to completely eliminate the virus, they do significantly reduce the amount of virus circulating in the blood. Most veterinarians recommend them – be sure to check with yours if you have any questions.
Adult horses are typically given two doses of vaccine. The second dose should be 3-6 weeks after the first, and should be given at least one month before mosquito season. Vaccinated adult horses generally need a booster shot annually.
Foals typically receive three doses: one at 3-4 months of age, another one month later, and a final dose 6-8 weeks after the second. They also receive a booster the following spring.
Whether or not you choose to vaccinate your horses for West Nile Virus, you should remove potential mosquito breeding grounds. These include areas of standing water such unused water troughs, old tires, and containers of accumulated rainwater, as well as piles of decaying organic matter such as leaves and manure. Add mosquito dunks or fish to continually-used water troughs and ponds to kill mosquito larva, and set up mosquito traps. Your local authorities may also set up aerial spraying for mosquito reduction.