Advances in diagnostics and treatments have greatly reduced the number of horses who succumb to Equine protozoal myeloencephalitis (EPM). This potentially debilitating neurological disease remains a threat to horses throughout the United States. Its range is spreading, too. Finding more effective ways to prevent and treat this disease continues to challenge researchers.
Horses can develop EPM when they ingest feed and water contaminated with Sarcocystis neurona, one-celled organisms called protozoa that are spread by opossums and carried by other wildlife. Less commonly, another protozoan, Neospora hughesi, causes the disease.
Source: Equus, April 14, 2017.
The lack of a good research model is one of the primary challenges EPM researchers must overcome—whether investigating treatments or potential vaccines: It is difficult to cause a horse to develop EPM in laboratory conditions.
Also see: EPM: The Master of Disguise, April 13, 2017. (Sponsored Content)
INSIGHTS: Three FDA-approved anti-protozoal drugs are now available to treat EPM:
- Ponazuril (tradename Marquis; generic name toltrazuril sulfone), an oral paste administered once daily for 28 days.
- Pyrimethamine and sulfadiazine (tradename Rebalance), an oral suspension administered once daily for as long as 120 days.
- Diclazuril (tradename Protazil), a pelleted, alfalfa-based top-dressing fed for 28 days.