West Nile Virus Confirmed in Horses in Pair of Washington Counties

The Washington State Department of Agriculture (WSDA) confirmed the presence of West Nile virus in two horses from Grant and Benton counties. The horses, which were not vaccinated or were under-vaccinated for the disease, are both recovering.

Photo: Adobestock

Photo: Adobestock
OLYMPIA – The Washington State Department of Agriculture (WSDA) confirmed the presence of West Nile virus in two horses from Grant and Benton counties. The horses, which were not vaccinated or were under-vaccinated for the disease, are both recovering. 
 
The Washington Animal Disease Diagnostic Laboratory in Pullman, operated by Washington State University, reported the positive test results to WSDA’s State Veterinarian’s Office last week. 
 
West Nile virus is spread by mosquitoes that have fed on infected birds. The disease sickens people, horses, birds, and other animals, but it does not spread directly from horses to people or other animals.
 
The disease is fatal to horses in about a third of the cases where clinical signs are apparent. However, most horses do not become ill and show no symptoms. Horses that do become ill can display loss of coordination, loss of appetite, confusion, fever, stiffness, and muscle weakness, particularly in their hindquarters.
 
In 2021, the USDA reported 220 equine cases involving West Nile virus. Numbers for 2022 are not yet posted.  - Source: WSDA