Examination of Risk Factors for Equine Protozoal Myeloencephalitis

1. Introduction

Equine protozoal myeloencephalitis (EPM) is a serious and often fatal neurologic disease of horses.^1–3 There are currently no known preventive measures for this disease. Studies of infectious diseases in other species have shown that control programs based on identified risk factors can be as important as implementation of vaccination programs.4 The purpose of this study was to identify potential risk factors for the development of clinical EPM.². Methods Horses presented to The Ohio State University Veterinary Teaching Hospital from 1992 through 1995 were eligible for enrollment. All horses that had any neurologic deficits diagnosed were enrolled in the case series if cerebrospinal fluid (CSF) analysis identified antibodies to Sarcocystis neurona using Western blot analysis or species-specific DNA using polymerase chain reaction (PCR). Two separate control series were identified; one group included horses with other neurologic diseases (neurologic controls), and the second included horses presented for reasons other than neurologic disease (nonneurologic controls). Horses with EPM were compared with the two control series independently to identify risk factors for disease. […]