Equine herpesvirus type 1 (EHM) myeloencephalopathy: a potential danger or a worthless illusion!
Subject Areas : clinical veterinary science
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Keywords: myeloencephalopathy, horse, herpesvirus,
Abstract :
Equine Herpesvirus Myeloencephalopathy (EHM), caused by Equine Herpesvirus type 1 (EHV-1), is a neurologic condition marked by ataxia, urinary retention, limb paralysis, and occasionally death. The disease can affect both vaccinated and unvaccinated horses, with a higher prevalence in older and female horses. EHV-1 exists in two main genotypes: neuropathogenic (D752) and non-neuropathogenic (N752), the former being more virulent. Transmission occurs through direct and indirect contact, including nasal secretions, contaminated equipment, and fetal fluids. Diagnosis is based on clinical signs, PCR testing, cerebrospinal fluid analysis, and histopathology. There is no definitive treatment; however, supportive care alongside antiviral, anti-inflammatory, and anticoagulant therapy may improve outcomes. Preventive measures rely on strict biosecurity, quarantine, and stress reduction. While vaccination may not prevent EHM, it can reduce respiratory disease and abortion associated with EHV-1. Early detection and proper outbreak management are essential for controlling disease spread and minimizing losses.
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