The Tennessee state veterinarian’s office has confirmed a horse with Eastern equine encephalomyelitis (EEE) in Gibson County, Tennessee. | Photo: Wikimedia Commons

The Tennessee state veterinarian’s office has confirmed a horse with Eastern equine encephalomyelitis (EEE) in Gibson County, Tennessee. The horse was euthanized, and all other horses on the premises were vaccinated, with boosters to follow in two weeks. The horse marks the state’s first equine EEE case.

EEE 101

Eastern equine encephalomyelitis is caused by the Eastern equine encephalitis virus, for which wild birds are a natural reservoir. Mosquitoes that feed on EEE-infected birds can transmit the virus to humans, horses, and other birds. Horses do not develop high enough levels of these viruses in their blood to be contagious to other animals or humans. Because of the high mortality rate in horses and humans, EEE is regarded as one of the most serious mosquito-borne diseases in the United States.