West Nile Virus – Is Your Horse At Risk?

West Nile virus is a mosquito-borne disease that causes inflammation or swelling of the brain and spinal cord. Since its discovery in New York in 1999, the incidence of West Nile virus in horses has more than doubled. Once horses show clinical signs of illness, the disease is fatal nearly 40% of the time

West Nile Virus Symptoms in Horses

These symptoms can be confused with rabies, EPM (“Possum Disease), equine encephalitis, and other serious neurological diseases. If you see these signs in your horse, see your veterinarian immediately.

  • Stumbling or tripping
  • Muscle weakness or twitching
  • Partial paralysis
  • Loss of appetite
  • Depression or lethargy
  • Head pressing or tilt
  • Impaired vision
  • Wandering or circling
  • Inability to swallow
  • Inability to stand up
  • Fever
  • Convulsions
  • Coma
  • Death

How do horses get West Nile Virus? 

The cycle starts with infected birds, which can travel long distances in a short amount of time. When a mosquito bites a bird carrying the West Nile virus, it too becomes infected. The mosquito then feeds on a horse, human or other mammal. Once a horse has been bitten, it may take only 5 to 15 days for signs of West Nile virus to appear.


There is no specific treatment for West Nile virus. Your veterinarian may be able to provide supportive therapy that can save your horses life. However, in addition to good mosquito control, there is now a vaccine that may aid in the prevention of disease caused by West Nile virus.

Mosquito Control Tips

  • Keep horses stabled during dawn and dusk, when mosquitoes are most active
  • Turn off lights that attract mosquitoes at night
  • Use fluorescent lights, which do not attract mosquitoes
  • Keep screens in stable windows
  • Eliminate common mosquito breeding areas like shallow stagnant water and puddles
  • Empty water collecting in buckets, tarps or tires
  • Clean water troughs once a week
  • Use mosquito repellent

The WNV Vaccine The U.S. Department of Agriculture has granted a full license for the first West Nile virus vaccine for horses. Only the Fort Dodge Animal Health vaccine is labeled for vaccination of healthy horses as an aid in the prevention of disease caused by West Nile virus. The recommended dose is two 1-mL doses, three weeks apart, plus annual revaccination. The vaccine is available only from a licensed veterinarian. It is important to remember that vaccines that protect your horse against Western, Eastern and Venezuelan equine encephalitis do not protect against encephalitis caused by West Nile virus. If you vaccinate against Western, Eastern and/or Venezuelan encephalitis, you should vaccinate against West Nile virus as well.

For More information, you can visit http://www.equinewestnile.com

Mosquito Control Products:
Eco-Trap Mosquito Trap System
The Original Lentek Mosquito Trap

0 comments on “West Nile Virus – Is Your Horse At Risk?

  1. Khan

    Well – Nobody posted in the forum for over a year and it was mailny all spam – but if you have any ideas for what you want to see, feel free to e-mail. Other than that, I am not entirely sure how its changed. The focus was always on issues, news and discussion on or about our great city – it hasn’t really changed but we are certainly open to suggestions for how to improve it.People are free to suggest blog topics for us to discuss – just contact us and let us know. Otherwise we just post the things that we are concerned about. We do have an excellent resource of political cartoons being drawn by a local artist I hope to take advantage of that a bit more – and if you would like to submit your own story feel free to contact us.


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