In the United States, the American Association of Equine Practitioners has designated Eastern and Western Equine Encephalytis, West Nile Virus, Tetanus and Rabies as "Core" vaccinations. This means that the AAEP believes that all horses in the US should be vaccinated against these diseases yearly. There are several other vaccinations that are considered "risk based" vaccinations, meaning that they should be given based upon the horse's risk of exposure. Risk factors can include geographic location, age and use of the horse and management of the horse.
Horse owners should contact their local veterinarian to discuss the recommended vaccinations for their area and situation.