All About Equine Influenza

Equine Influenza is a highly contagious respiratory disease that can be spread directly and indirectly to horses.

Incubation period is 1-3 days post exposure and symptoms usually appear 3-5 days after the horse has been exposed.

Symptoms include:

  • Fever
  • Poor appetite
  • Dry harsh cough
  • Nasal discharge

Younger horses have more server symptoms from equine influenza than older horses.


  • Direct transmission: saliva, nasal discharge, and air (droplet from coughing and snorting within 50 yards).
  • Indirect transmission: community water troughs, shoes, clothing, feeders, equipment, tack, brushes, trailers, and hands.

If your horse does become infected contact your veterinary so the horse can be treated with proper supportive care.

The virus can be spread for 7-10 days post infection and horses should be isolated from other horses at your barn, horse shows, trail rides, and traveling for 14 days.

Equine Influenza does not spread to humans.


Prevention is key to keeping your horse and barn healthy.

  • Vaccinated horses can still become infected with equine influenza and shed the virus. Horses that have had the vaccine within 2-4 months should be protected. This vaccine should be given to your horse twice a year. Vaccines are important because they help prime the immune system and help prevent the risk of infection and aid in the prevention of disease. Work with your veterinary to make sure your horse is receiving proper vaccines based on the location of your horse, if you travel with your horse, and exposure to other horses.
  • Bring your own water bucket to shows with you.
  • Don’t let your horse touch noses with strange horses. Always tie your horse away from others.
  • Wash your hands or use hand sanitizer to help prevent spreading the virus.
  • Disinfect equipment, trailer, clothes, shoes, etc. after shows or traveling.
  • If you have an infected horse at your barn make sure to always take care of the infected horse last and wash your hands.

*If you have any questions or concerns please do not hesitate to contact your County Livestock Extension Agent by email or call your local veterinarian.


  1. American Association of Equine Practitioners, Equine Influenza.

Posted: March 17, 2020

Category: 4-H & Youth, Agriculture, Livestock
Tags: Brittany Justesen, Equine, Equine Influenza, Horse Health, Horses, UF/IFAS Extension

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