Summary: The parasites causing equine protozoal myeloencephalitis are ubiquitous in U.S. horses, yet fewer than one percent of the horses that carry one or both of the parasites develop clinical symptoms of EPM. Find out more about these parasites and which horses may be more predisposed to EPM.
Source: The Horse.
Horses cannot catch EPM from each other; rather, they’re exposed to the microbes via feed or water contaminated by opossum scat. Exposure and subsequent infection can lead to neurologic clinical signs such as clumsiness, muscle atrophy and lameness.