The mosquito-borne illness, West Nile Virus, has been found in five East Tennessee horses.
Two of those horses are from Washington County while the other three hail from Bradley, Cumberland and Sullivan counties.
The State Veterinarian Dr. Charles Hatcher has confirmed the sickness, blaming mosquitoes and other biting insects.
Hatcher warns horse owners to take preventative measures.
The best way to prevent the illness is the vaccine.
However, sick horses cannot directly infect people with West Nile Virus.