The West Nile virus has been around the US and North America for about 10 years now. The West Nile virus can be life threatening to both horses and humans alike and should be taken very seriously. The way the disease is transmitted to horses is by a mosquito bite. A mosquito takes a meal from a bird infected with WNV, and then goes and feeds on a horse. Some horses infected with the disease show no signs at all; meanwhile the virus causes inflammation of the spinal cord and brain and can often be fatal.

The best way to combat the West Nile virus is to prevent your horse from getting it in the first place. Here are a few tips to help keep your barn and horse mosquito free:

1. Eliminate potential mosquito breeding areas. Get rid of old tires (a lot of people use tires to hold tarps on top of manure piles) and any other plastic receptacles as well as anything that can hold unwanted water. Eliminate any standing, or stagnant water.
Clean your roof gutters regularly. Millions of mosquitoes can breed in roof gutters each season.
2. If not possible to eliminate all breeding sites, spay with larvicides, but do this with caution and consult a mosquito specialist.
3. Clean your horse’s water trough regularly and always replace with fresh water. Don’t just add fresh water to the old water.
4. Bring your horse inside during peak mosquito hours. Mosquitoes are most active at dusk and dawn.
5. Place screens around stalls if mosquitoes are especially bad in your area.
6. Keep the lights out in your barn at night and at dusk and dawn. Lights attract mosquitoes.
7. Spray your horse with a fly spray made to repel mosquitoes. This may deter mosquitoes from biting your horse.
8. Keep all birds including chickens and ducks well away from the stable. Remove them completely if possible.
9. Protect yourself as well; wear long, covering clothing when going outdoors in the evening. Cover your skin and apply mosquito repellent.
10. Consider getting your horse vaccinated for the West Nile Virus. The vaccine is an important step in the prevention of West Nile Virus. Without the vaccine horses affected have a 65 percent chance of recovery if treated. 35 percent of all horses affected are likely to die of the illness.

Symptoms your horse may show if infected with West Nile Virus are:

Lack of coordination
Excitability and seizures
Stumbling and limb weakness
Facial paralysis
Droopy eyelids and lower lip
Sleepiness, dullness and listlessness
Inability to get up
Mild fever, blindness and muscle trembling

If your horse is displaying any of the above symptoms or you suspect he may be infected with West Nile virus, call your vet immediately. There is no specific treatment for West Nile virus, but veterinarian support is strongly recommended. Also it is important to diagnose WNV because infection is an indication that mosquitoes carrying the virus are in the area and need to be eliminated.