West Nile Virus in WA

This was posted Aug. 1 by the Washington State Department of Agriculture.

West Nile virus found in Moses Lake and Toppenish area horses—first cases in 2008

OLYMPIA – West Nile virus (WNV), a potentially fatal disease in equines, has been confirmed in two horses, one in Moses Lake and the other in the Toppenish area, the Washington State Department of Agriculture (WSDA) announced today.

These are the first confirmed cases this year of horses contracting West Nile virus in Washington. Last year, eight horses were confirmed for the disease, all in Yakima County.

Washington State University’s Animal Disease Diagnostic Laboratory in Pullman reported the positive test results to WSDA today.

The 24-year-old gelding quarter horse in Moses Lake appears to be recovering. The Yakima County horse, a five-year-old quarter horse mare, has been euthanized. Neither horse was vaccinated for WNV.

“The best way to protect a horse from West Nile infection is vaccination,” said Dr. Leonard Eldridge, state veterinarian. “Horse owners with concerns should contact their veterinarian for information on vaccines and annual booster shots.”

Eldridge also recommended that horse owners take measures to reduce mosquito populations by removing standing water from yards and barns and changing water in troughs or bird baths that could be a source of mosquito breeding.

West Nile virus is spread by the bite of an infected mosquito and can infect people, horses, many types of birds, and other animals. Humans cannot contract WNV through contact with an infected horse. Infected horses do not spread the disease to other horses or animals. Mosquitoes become carriers when they feed on an infected bird. Horses that contract WNV may show signs such as loss of coordination, loss of appetite, confusion, fever, stiffness and muscle weakness, particularly in the
hindquarters. Many horses and other animals contracting WNV do not become ill and show no symptoms at all. About one-third of horses that become ill die.

Veterinarians and horse owners should report potential cases of West Nile virus in horses by calling the State Veterinarian’s Office at (360) 902-1878.

More WNV information is available on the following Web sites:
• Department of Health: www.doh.wa.gov/WNV
• Washington State University: www.wnv.wsu.edu
• Department of Agriculture: www.agr.wa.gov
Go to the Animal Health section after clicking on “Food and Animals.”