The virus is spread by the bite of a mosquito that has fed on an infected bird or rodent. Humans can also become infected, as documented by one confirmed case involving a Camden County woman in mid-July. Signs or symptoms of EEE in horses are usually noticed about five days after they are bitten by an infected mosquito. Initially, horses are depressed and quiet. Other signs include impaired vision, aimless wandering, head pressing, circling, inability to swallow, irregular staggering gait, paralysis, convulsions, and death.
Most deaths occur within two to three days after symptoms appear.
About 90 percent of the equine who show signs of the disease will die and the remaining 10 percent will be permanently impaired, said State Veterinarian Dr. David Marshall. The symptoms of EEE are similar to those of rabies, making it essential that a definitive diagnosis be made. There is no specific treatment for animals affected with EEE, making vaccinations essential to the prevention of the disease. An initial vaccination consists of two vaccine injections 30 days apart. It is recommended that booster vaccinations be given every 6 months, preferably in the early spring and late summer or early fall.