FOR IMMEDIATE RELEASE
THURSDAY, JULY 23, 2009
||Dr. Tom Ray, director of animal health programs
NCDA&CS Veterinary Division
Three horses test positive for a mosquito-borne disease
RALEIGH — North Carolina has recorded its first three equine fatalities due to a mosquito-borne disease this summer.
Two horses in Beaufort County were the first N.C. equine to test positive this year for Eastern Equine Encephalomyelitis, State Veterinarian Dr. David Marshall announced today. The unvaccinated horses were treated by a veterinarian and euthanized within the past two weeks after presenting symptoms of EEE.
The third horse was confirmed positive at the department’s Rollins Animal Disease Diagnostic Laboratory this week after being euthanized in Columbus County. There have been no reported cases of West Nile virus in horses in North Carolina to date.
State officials have seen a decline in equine EEE and WNV cases the last few years, but they caution equine owners to continue the vaccination protocol against these potentially fatal diseases because the diseases are historically cyclical in nature, with years of few reported cases followed by years with widespread disease.
The vaccines consist of an initial shot followed three weeks later by a booster shot. The vaccine is not fully effective until several weeks after the booster is given, so the earlier in the season the vaccine is administered, the more effective it will be. Equine owners should consult their private veterinarian about an appropriate vaccination schedule.
“The best way to prevent these possibly fatal diseases is to vaccinate horses against them. The cost of prevention is minimal compared to losing an animal to this fatal disease,” Marshall said. “I encourage horse owners to continue to take measures to protect their animals because these diseases will continue to pose a threat to horses during the summer and fall months.”
There is also speculation that several years of drought kept mosquitoes — and mosquito-borne diseases — at bay, so this year’s wetter weather could bring more mosquitoes.
Symptoms of EEE, also known as “equine sleeping sickness,” include impaired vision, aimless wandering, head pressing, circling, inability to swallow, irregular staggering gait, paralysis, convulsions and death.
Symptoms of WNV in horses can include loss of appetite and depression, fever, weakness or paralysis of hind limbs, convulsions, impaired vision or hyperexcitability. A veterinarian should be consulted if an animal is exhibiting symptoms of either of these diseases.
People, horses and birds can become infected from a bite by a mosquito carrying the virus, but there is no evidence that horses can transmit the virus to other horses, birds or people through contact. People should take precautions to limit the breeding grounds for mosquitoes to protect humans and animals.