An advisory by the state veterinarian and other animal health care officials has been issued to horse owners regarding the possible re-emergence of eastern equine encephalitis. The disease is transmitted, much like the West Nile virus, through mosquitoes.

“Horse owners should be aware of symptoms of viral encephalitis and consult their local veterinarian should their horse develop any signs associated with this group of diseases,” said state veterinarian Ron Wilson.

The first case in Tennessee was confirmed some time last week in Anderson County. Cases have also been reported in the nearby states of Florida, Georgia, North Carolina and South Carolina.

Health officials are also concerned about other mosquito-borne diseases because of the expected increase in the number of West Nile cases during the summer months.

Both equine encephalitis and West Nile virus are transmitted when a mosquito feeds on an infected bird and then passes it on to horses.

Even though eastern equine encephalitis occurs sporadically in Tennessee, the mortality rate in horses is high, according to Wilson. He also believes the spread of West Nile has increased awareness of other nervous system diseases, including eastern equine encephalitis.

It is extremely important for horse owners to know and understand the symptoms for both West Nile and eastern equine encephalitis. Symptoms for both diseases include decreased alertness, blindness or impaired vision, aimless wandering or circling, head pressing, inability to swallow and convulsions.

“Definitive diagnosis is important in tracking the spread of viral infections,” Wilson said. “It requires a commitment on the part of the horse owners working with their local veterinarian and verifying test results through laboratory analysis.”

Vaccines protecting against encephalitis and western equine encephalitis, a variant of the disease, are currently available. An approved West Nile vaccine is also available. Wilson urges horse owners to review their horse’s immunization records.

The State Department of Agriculture’s Kord Animal Laboratory located in Nashville provides diagnostic services for livestock owners and private veterinarians. For more information, please call the state veterinarian’s office at 615-837-5120.