Equine Protozoal Myeloencephalitis: An Updated Consensus Statement with a Focus on Parasite Biology, Diagnosis, Treatment, and Prevention

J Vet Intern Med. 2016 Mar-Apr;30(2):491-502. doi: 10.1111/jvim.13834. Epub 2016 Feb 9.

Abstract

Equine protozoal myeloencephalitis (EPM) remains an important neurologic disease of horses. There are no pathognomonic clinical signs for the disease. Affected horses can have focal or multifocal central nervous system (CNS) disease. EPM can be difficult to diagnose antemortem. It is caused by either of 2 parasites, Sarcocystis neurona and Neospora hughesi, with much less known about N. hughesi. Although risk factors such as transport stress and breed and age correlations have been identified, biologic factors such as genetic predispositions of individual animals, and parasite-specific factors such as strain differences in virulence, remain largely undetermined. This consensus statement update presents current published knowledge of the parasite biology, host immune response, disease pathogenesis, epidemiology, and risk factors. Importantly, the statement provides recommendations for EPM diagnosis, treatment, and prevention.

Keywords: Encephalitis; Equine myeloencephalopathy; Equine neurologic; Equine protozoal disease; Myelitis; Neospora hughesi; Sarcocystis neurona.

Publication types

  • Review

MeSH terms

  • Animals
  • Antiprotozoal Agents / therapeutic use*
  • Coccidiosis / drug therapy
  • Coccidiosis / veterinary
  • Encephalomyelitis / drug therapy
  • Encephalomyelitis / parasitology
  • Encephalomyelitis / veterinary*
  • Horse Diseases / drug therapy
  • Horse Diseases / parasitology*
  • Horse Diseases / pathology
  • Horses
  • Neospora / isolation & purification
  • Practice Guidelines as Topic*
  • Sarcocystis / isolation & purification
  • Sarcocystosis / drug therapy
  • Sarcocystosis / veterinary

Substances

  • Antiprotozoal Agents