Vaccines are the first line of defense against the spread of disease. They are not a guarantee your horse won’t get sick, but they reduce his risk and lessen the symptoms. Knowing which vaccines to give and when can be overwhelming. The American Association of Equine Practitioners (AAEP) is an organization that keeps equine practitioners up-to-date on medical and surgical information. They provide Vaccinations Guidelines that gives recommendations on Core Vaccination Guidelines and Risk-Based Vaccination Guidelines.
The principles of AAEP vaccine recommendations are based on the following:
A “standard” vaccination program for all horses does not exist. Each individual situation requires evaluation based on the following criteria:
- Risk of disease (anticipated exposure, environmental factors, geographic factors, age, breed, use, and sex of the horse)
- Consequences of the disease (morbidity/mortality, zoonotic potential)
- Anticipated effectiveness of the selected product(s)
- Potential for adverse reactions to a vaccine(s)
- Cost of immunization (time, labor and vaccine costs) vs. potential cost of disease (time out of competition; impact of movement restrictions imposed in order to control an outbreak of contagious disease; labor and medication if, or when, horses develop clinical disease and require treatment, or loss of life.)
The first consideration of an immunization program is referred to as the Core Vaccines:
- Eastern and Western encephalomyelitis
- West Nile virus
These vaccines are deemed essential for all horses to receive annually no matter the horse’s age, breed, gender or geographical location.
In contrast, risk-based vaccinations are those given for specific reasons due to increased risk based on age, breed, gender, activity and/or geographical locale. These include:
- Equine influenza
- Equine herpesvirus (rhinopneumonitis)
- Strangles (Streptococcus equi)
- Equine viral arteritis (EVA)
- Potomac horse fever (PHF)
- Rattlesnake bite
- Rotaviral diarrhea
Depending on the incidence of disease outbreak in your local area, there might be need to use one or more of these risk-based vaccines at some point in time. Some are intended solely for use in breeding animals (EVA), or especially targeting protection of foals (botulism, Rotavirus). Some are given to mitigate a disease outbreak in the local area (strangles, leptospirosis, PHF and anthrax).
Respiratory Virus Vaccines
Respiratory virus vaccines are recommended and in commonplace use for horses that travel and/or compete since they are exposed to large numbers of horses from all over. In addition, competition horses have an overlay of stress that impacts the immune system, rendering them more susceptible to acquiring disease. To mitigate the risk of a potential respiratory viral outbreak, USEF (United States Equestrian Federation) now requires immunization of all horses for influenza and herpesvirus within six months of participation in USEF shows. For decades, the Federation International Equestrian (FEI) has required influenza boosters every six months for equine competitors at FEI events.
The Bottom Line
Which vaccines you select for your horse is best considered after a conversation with your veterinarian as to how to best curtail infectious disease issues for your horse. There are many manufacturers producing a large variety of safe and effective vaccine options. Safety and efficacy studies are required by the government before licensing to ensure the highest degree of immune protection and the best safety protocols in administration.