By STEVE BROWN
A Washington state horse was euthanized this week after it contracted West Nile virus, and four other horses in Idaho and Oregon were diagnosed with the disease.
Veterinarians are urging horse owners to vaccinate their animals.
A 2-year-old gelding in Yakima County, Wash., was put down after it contracted the virus and its condition worsened, Washington state veterinarian Leonard Eldridge said. Confirmation of the illness came from the Washington Animal Disease D …