EEE Confirmed In Virginia

Ten horses in Virginia have died of neurological symptoms thought to be caused by Eastern equine encephalitis (EEE), according to Bruce Akey, DVM, director of the state's laboratory system and president of the American Associa-tion of Veterinary Lab-oratory Diagnosticians. The virus has been isolated and confirmed in six of the horses at the National Veterinary Services Laboratory in Ames, Iowa. Samples from one horse were not sufficient for testing.

EEE is spread from wild birds to horses and humans by the bite of an infected mosquito. Symptoms of the illness include fever, loss of appetite, depression, abnormal white blood cell counts, and an elevated heart rate.

Nine of the horses were from southeastern Virginia and were housed on farms near the towns of Suffolk and Chesapeake. One of the horses submitted was from North Carolina, about eight miles away from the Virginia border. A Virginia practitioner submitted the North Carolina-based horse. Microscopic lesions were found in the horse's brain suggesting EEE, although EEE has not yet been cultured.

"We are recommending to owners that they vaccinate," said Akey. "The product is a killed vaccine product good for one year. If you're in that endemic area of southeast Virginia, however, vaccinate twice a year. Unfortunately, of the horses which have been submitted, none had been properly vaccinated as far as we're able to tell from talking to the owners."

Akey attributes the flare-up of EEE in Virginia to at least three factors. One, the wet and rainy weather the state has been experiencing has produced a bumper crop of mosquitoes; two, horses were not properly vaccinated; and three, this year's strain of the virus seems to be fairly aggressive.

EEE appears in Virginia almost every year, normally with only one or two positive cases detected in the southeastern corner of the state where there is abundant standing water for mosquitoes to breed. Akey said that this is the highest number of cases they have had in one season.

Vaccination is important. Akey also instructs owners to remove standing water around the farm to prevent mosquito breeding, and to keep mosquitoes out of barns as much as possible. He also recommends use of insect repellents on the horses several times a day.

Akey said Virginians have responded well to vaccination recommendations. "The media has made quite a bit of a splash of this situation, so the owners are very aware (of EEE). We've may have gotten more (cases) turned in than in the past because of the media coverage."

About the Author

Stephanie L. Church, Editor-in-Chief

Stephanie L. Church, Editor-in-Chief, received a B.A. in Journalism and Equestrian Studies from Averett College in Danville, Virginia. A Pony Club and 4-H graduate, her background is in eventing, and she is schooling her recently retired Thoroughbred racehorse, Happy, toward a career in that discipline. She also enjoys traveling, photography, cycling, and cooking in her free time.

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