West Nile virus has been found in two horses at Charles Town Races & Slots in West Virginia, the Associated Press reported.
"They showed symptoms of being stiff and irritated," Judi Rice, sanitation supervisor with the Jefferson County Health Dept., told the county board of health the week of Sept. 8. "One of them fell and could not get up."
The mosquito-borne virus has been detected in dead birds in 22 of West Virginia's 55 counties this year. The first equine case of the virus was discovered in a horse in Hancock County, where Mountaineer Race Track & Gaming Resort is located.
State veterinarian Martha Hunt said she wasn't aware of the infected horses at Charles Town, according to the Associated Press. Two horses at the track were diagnosed with the virus in 2002, Rice said.
West Nile can cause flu-like symptoms in humans and potentially fatal swelling of the brain. No human cases have been reported in the state this year. The spread of the disease is expected to slack off in the fall as cooler temperatures slow the activity of mosquitoes.
Rice said racetrack officials have worked with health officials to reduce areas where mosquitoes can breed.