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Protect Your Horse!

May contain: horse, mammal, animal, person, human, and equestrian

Vaccinate today if your horse hasn’t already had the initial series of two WNV vaccinations 3-4 weeks apart plus annual boosters.  Horses are not fully protected until they have had two initial injections and are up to date with booster vaccinations.

In 2012, a total of 22 horses were confirmed positive for WNV. The positive horses were located in thirteen counties in California.  Eight of the positive horses were euthanized. Compare these numbers to the 2004 year when 540 horses were infected of this number 228 were euthanized.


Birds carrying the West Nile Virus are bitten by mosquitoes that transfer the virus to horses, other birds and other mammals including humans. Birds in the crow and jay family are thought to be the most common carriers, although some other species including waterfowl may be carriers of WNV. WNV is not transferred from horse to horse or horse to human.


Horses that have contracted the WNV may have elevated temperature, listlessness, apathy, weakness, poor coordination, partial or full paralysis, nervousness, lethargy or drowsiness, and seizures. Many horses are infected with WNV and show few, if any symptoms.


WNV can be fatal, but many horses recover fully and are able to take on a normal workload. Others may show some signs of weakness or neurological damage.


Drug, vitamin, and fluid therapies may help although there is no specific course of treatment. Veterinarian supervision is essential.