The Facts on EHV-1

As horse owners, we want to make sure our horses stay as healthy as possible.  Part of that responsibility includes understanding common equine diseases, so that we can prevent them before they start.  Here’s some quick facts on the virus EHV-1.

cartoon horse with a cold
EHV-1 is a respiratory infection
  • EHV-1 is an abbreviation for Equine herpesvirus-1.
  • It is 1 of 4 EHV strains.
  • It is a virus, meaning it does not respond to antibiotics.
  • It routinely causes upper respiratory infection in young horses, under 2 years old.
    • Symptoms include fever, lethargy, nasal discharge, loss of appetite, and persistent cough.
    • The virus usually runs its course and horses recover without incident.
  • In rare cases, adult horses show symptoms of respiratory infection, and develop a secondary disease called equine herpes myeloencephalopathy (EHM).
  • EHM is a serious neurological disease.
    • Symptoms include lack of coordination, inability to stand, leg swelling, and inability to eliminate waste. These symptoms are also commonly found in other neurological diseases such as West Nile Virus.
  • Diagnosis is done by a veterinarian with a nasal swab test.
  • Because it is a virus, supportive care is the only treatment option.
  • EHV-1 is contagious and spread through horse-to-horse contact.
    • It is transferred through the air up to 35 feet.
    • It can survive on surfaces up to 7 days under normal circumstances, but can remain alive for a maximum of 1 month under perfect environmental conditions.
  • EHV-1 is easily killed with disinfectants.
  • At-risk farms should observe quarantine procedures for a minimum of 2 weeks, keeping horses isolated and disinfecting equipment, tack, clothing, and other surfaces.
  • Farms with confirmed cases should observe quarantine procedures for longer, about 4 weeks.
  • If there is an outbreak in your area, it is best to reduce the risk of exposure.
    • Keep your horses at their home base.
    • Don’t let your horse meet new friends.
    • Don’t share equipment, tools, etc.

To stay up to date and monitor disease outbreaks in your area, visit the Equine Disease Communication Center’s website <http://www.equinediseasecc.org>.