West Nile virus has been found in a horse north of Hermiston, Umatilla County officials announced Wednesday.
The results were confirmed through testing at the Oregon State University Veterinary Diagnostic Lab in Corvallis, a news release said.
“This is the first detection in a horse in Umatilla County since 2009. The positive horse comes five weeks after officials first detected the virus in mosquitoes in Umatilla County,” the release said.
Both horses and humans get the virus from mosquitos that have fed off infected birds, the release said. Most people who contract it don’t get sick, although some develop flu-like symptoms, said Sarah Williams, Umatilla County Public Health Division director, in the release.
“In rare cases West Nile may cause encephalitis, or inflammation of the brain. Individuals with severe or unusual headaches should seek medical care as soon as possible,” she said in the release.
Infected horses show neurological signs, including weakness, lack of coordination affecting the hind limbs and muscle tremors, the release said. A vaccine is available from veterinarians, it said.