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Equine Disease

Equine Herpes Virus Type 1 Neurological

Equine Herpes Virus Type 1 Neurological (EHV-1) is a serious disease in horses involving inflammation of small blood vessels in the spinal cord and/or brain.

EHV-1 Neurological disease can be transmitted:

  • through the air from respiratory infection
  • by direct or close contact between horses
  • by contact with contaminated equipment, clothing, or hands.

A genetic test for identifying latent equine carriers of EHV-1 Neurological is available.


Horses with EHV-1 Neurological disease have a weakness and paralysis of the muscles of the hind limbs that causes lack of coordination, gait abnormalities and the inability to stand up from a sitting position.

The time between an initial EHV-1 infection of the respiratory tract and the onset of neurological signs is about 8 - 12 days. The neurological symptoms appear suddenly and reach peak intensity within 48 hours.


Horses with symptoms should be isolated and kept 40 feet or more from other horses. Owners should contact their veterinarian.

While vaccines are available, none are specifically labeled for the neurological form of EHV-1.

EHV-1 Neurological is resistant to vaccination and the prognosis for non-recumbent horses is favorable, but very poor for horses that remain down longer than 24 hours.

More information on EHV-1.