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Kittitas County horse hit with West Nile virus infection 

OLYMPIA — West Nile virus (WNV), a potentially fatal disease in equines, has been confirmed in a one-year-old Quarter horse gelding located in Ellensburg, the Washington State Department of Agriculture (WSDA) announced today. The horse was euthanized and had not been vaccinated for West Nile virus.

It is the third horse of the year reported by the Washington Animal Disease Diagnostic Laboratory in Pullman as a positive case of West Nile virus. On July 24, the lab reported the first two cases—a horse in Toppenish that was euthanized and a Prosser horse that was recovering.

The veterinarian that treated the Ellensburg horse reported it had traveled to Othello to pasture recently but returned to Kittitas County two weeks ago.

WNV is spread by mosquitoes that have fed on an infected bird. The disease can sicken people, horses, many types of birds, and other animals. It is not spread from horses to other animals.

Last year, Washington had confirmed cases of WNV in horses in Yakima, Grant, Benton and Kittitas counties. In previous years, WNV horse cases have been detected in Western Washington as well. Virtually all of the horses that acquired West Nile virus last year were not current with vaccinations.

WNV is fatal in about one-third of all horses that show clinical signs, although most horses do not become ill and show no symptoms at all. Those that do become ill display loss of coordination, loss of appetite, confusion, fever, stiffness, and muscle weakness, particularly in the hindquarters.

"Vaccinating your horse or getting the proper booster shots is the best way to help protect your animal," Dr. Leonard Eldridge, state veterinarian said. Eldridge advises that horses vaccinated last year but that weren't yet given a booster this year be given a booster shot now. It should become effective in two weeks.

The state veterinarian also recommends that horse owners take measures to reduce mosquitoes. Precautions include removing standing water from yards and barns and regularly changing water in troughs or bird baths that could be a source of mosquito breeding.

Veterinarians who learn of potential WNV cases in horses or other animals should contact the State Veterinarian's Office at (360) 902-1881.

Additional information on WNV can be found at the state Department of Health Web site at www.doh.wa.gov/WNV and at the U.S. Department of Agriculture Web site at www.aphis.usda.gov/vs/nahss/equine/wnv.

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