Eastern equine encephalitis (EEE) is a rare but serious viral disease spread by mosquitoes that can affect people and horses. EEE can also cause disease in captive birds such as the ring-necked pheasant, emu, ostriches, quail and ducks. EEE infection and disease can occasionally occur in other livestock, deer, dogs, other mammals, reptiles and amphibians. EEE is transmitted by the bite of an infected mosquito. Mosquitoesbecome infected by feeding on infected birds. Infected mosquitoes will then occasionally feed on horses, humans and other mammals. Several species of mosquitoes can become infected with the EEE virus (EEEV). EEE is not spread person-to-person, from people to animals or from animals (other than mosquitoes) to people. Most people bitten by an infected mosquito will not develop any symptoms. Severe cases of EEE infection begin with the sudden onset of headache, high fever, chills, and vomiting. The illness may then progress into disorientation, seizures, encephalitis (inflammation of the brain) and coma. Approximately a third of patients who develop EEE die, and many of those who survive have mild to severe brain damage. It takes 4-10 days after the bite of an infected mosquito to develop symptoms of EEE.