Eastern Equine Encephalitis (EEE) in NC

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The first 2 cases of Eastern Equine Encephalitis Virus (EEE), also known as sleeping sickness and blind staggers, for 2014 were officially reported last Friday, August 8. EEE is a virus that is transmitted by mosquitoes and attacks the nervous system in horses, thus causing death or permanent brain damage if the horse does survive. Both horses, one in Carteret County and one in Bladen County, were euthanized. Last year North Carolina had 15 reported cases of EEE by the end of mosquito season.

Once bitten by an infected mosquito, it may take anywhere from 3-10 days for horses to start showing clinical signs of EEE. Early signs of EEE are severe depression, a high fever of 105 degrees Fahrenheit, lack of appetite, and not responding to touch. EEE is a fast acting virus, so horses will develop later symptoms of the disease such as: knocking down fences and walls, blindness, ‘staggering’/being unsteady, and being unable to control their limbs. Horses usually die within 2-3 days of showing clinical signs of EEE. There is no cure for EEE. Around the clock, intensive nursing and Veterinarian care can save an infected horse’s life, but since EEE attacks the nervous system, the horse will have permanent brain damage. Prevention is the best protection from EEE.

Vaccinate your horses for EEE. The first time your horse is vaccinated, they will be given 2 injections, by your vet, about 2-4 weeks apart. After that, horses will require a booster shot every year since immunity for EEE can wear off. It is best to vaccinate in the early spring, before mosquito season, to give your horse a chance to build up immunity. If you haven’t already, start a mosquito control program. Mosquitoes breed in still water, so look for and drain places with standing water (like spare tires collecting rainwater) as often as you can. In wet summers, when there are lots of puddles for mosquitoes to breed in, you can try adding a few drops of oil-based insect repellent in the puddles to kill mosquito larvae, also known as ‘wiggles’. Protecting your horses with fly sheets can also be a good idea.

Lastly, mosquitoes can transmit EEE to humans too (the disease cannot travel between an infected horse to a human or vice versa), so remember to wear mosquito repellent yourself this summer!