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N.C. Sees its Third Case of Eastern Equine Encephalitis of the Year

close up of horse's muzzle
Update: A fourth case of Eastern Equine Encephalitis has been confirmed in Duplin County. More information:

As a third case of Eastern Equine Encephalitis is confirmed in North Carolina, horse owners are encouraged to update vaccinations and be aware of signs of EEE infection.

The North Carolina Department of Agriculture and Consumer Services’ Veterinary Division said Thursday that a horse that died in Onslow County has tested positive for EEE. A previous EEE case was confirmed in Onslow County on July 11. The first North Carolina case of the year was reported on July 9 in a horse from Richmond County that was euthanized after contracting the virus.

EEE is spread by mosquitoes and causes brain and spinal cord inflammation. Katie Sheats, NC State College of Veterinary Medicine assistant professor of equine primary care, said signs of infection could include a range of symptoms from fever, impaired vision and aimless wandering to leaning on structures and walking in circles. Horses may also have difficulty swallowing, may stumble when walking, have seizures or experience unexplained, sudden death. It can take three to 10 days for EEE signs to appear.

Sheats said EEE is fatal in 90 percent of infected horses. Most cases are reported in the late summer and early fall. EEE vaccination, the most effective prevention tool, is readily available and is preferably administered by a veterinarian to ensure vaccine quality and correct timing of administration. Suspected EEE cases should be immediately reported to a primary care veterinarian.

Humans, other horses and birds cannot contract EEE directly from an infected horse, though infection may occur from a bite by a mosquito carrying the disease. Humans are rarely infected with EEE and exposure risk is minimized by using insect repellent and covering exposed skin, especially during outdoor activities at dusk and at night when mosquitoes are most active, said Sheats.

For more information on protecting horses from EEE, Sheats answers common questions here.

Further resources:

NC State Equine Veterinary Service

North Carolina Department of Agriculture and Consumer Services’ Veterinary Division

North Carolina Veterinary Medical Association

The Centers for Disease Control and Prevention