Ask an Expert

EPM Vaccine

March 18, 2013

Find out whether you can vaccinate your horse against equine protozoal myeloencephalitis.

Ask an ExpertQuestion:

I live in north central Virginia and have an 11-year-old gelding. Can/should I vaccinate him against EPM? Can this vaccine be given with other vaccines, or should it be done at a separate time?

For the answer to this question, we consulted Dr. Sandi Farris with the American Association of Equine Practitioners.


In the past, equine protozoal myeloencephalitis (EPM) vaccines were available on the market for use in horses. Protection in those horses was, unfortunately, poor, and the vaccines were removed from manufacture. As of now, there is no USDA-approved vaccine against EPM. What a help it will be when there is one with a high level of protection!

The best thing horse owners can do now to protect against the protozoal disease is minimize the intermediate hosts (opossums, cats, raccoons and skunks are most likely culprits) by keeping grain and water sources secured, decreasing host access to horse pastures, and keeping your horses as healthy and stress free as possible. buy cheap viagra I am sure the ongoing research will, one day, lead to a useful vaccine.

Dr. Sandi Farris, member of the American Association of Equine Practitioners