North Carolina officials say two horses --including one in Eastern Carolina-- have died from Eastern Equine Encephalomyelitis, a mosquito-borne disease.
According to state officials, an 18-month-old Paint from Carteret County and a 3-year-old Quarter horse from Bladen County, showed signs of generalized weakness, stumbling, depression and inability to stand or eat.
The horse in Carteret County was euthanized on July 21, and the Bladen County horse died on Aug. 2, state officials said. Neither of them were vaccinated.
They are North Carolina's first reported cases of EEE in horses this year, according to the state. Earlier this summer, New Hanover County officials reported that the disease was found in a chicken flock.
North Carolina recorded 15 EEE cases in horses in 2013.
The disease causes inflammation or swelling of the brain and spinal cord, and is usually fatal, said state officials. Symptoms include impaired vision, aimless wandering, head pressing, circling, inability to swallow, irregular staggering gait, paralysis, convulsions and death.
Once a horse has been bitten by an infected mosquito, it may take three to 10 days for symptoms to appear.
"If your horses exhibit any symptoms of EEE, contact your veterinarian immediately," said State Veterinarian David Marshall. "Several serious contagious diseases, such as West Nile virus, equine herpes virus and rabies, have similar symptoms and should be ruled out."
EEE is preventable with vaccination. Marshall said owners should talk with their veterinarians about vaccines to not only protect horses from EEE, but also from the West Nile virus.
The vaccinations initially require two shots, 30 days apart, for horses, mules and donkeys that have no prior vaccination history. Marshall suggests getting a booster shot every six months.
State officials said mosquitoes can breed in any puddle that lasts longer than four days. Removing any source of standing water can reduce the chance of exposing animals to EEE or West Nile. Keeping horses in stalls at night, using insect screens and fans, turning off lights after dusk, and using insect repellants can also help protect animals from mosquitoes.
There is no evidence that horses can transmit the virus to other animals or people through direct contact, said health officials.