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Bureau of Disease Control

Eastern Equine Encephalitis

What Is Eastern Equine Encephalitis?

Eastern Equine Encephalitis (EEE) is a viral illness that can cause inflammation of the brain. In warm weather, the virus reappears in mosquitoes and birds. Similar to West Nile Virus and St. Louis Encephalitis, a mosquito then bites the bird and can in turn bite a mammal or a person. EEE can produce severe disease in horses, some game birds and people. Most cases of EEE in the United States occur in east coast and gulf coast states.

What are the symptoms?

Progress of the disease is very rapid. Symptoms range from mild flu-like illness to encephalitis, coma and death.

How is Eastern Equine Encephalitis treated?

There is no specific cure for Eastern Equine Encephalitis. It is caused by a virus, so antibiotics won’t help. In mild cases, physicians recommend the same remedies you would use for other viruses, such as the flu: drink plenty of water, resting in bed, drinking plenty of fluids, and taking medication such as acetaminophen or ibuprofen to relieve fever and discomfort. In more severe cases treatment may include hospitalization, intravenous fluids, and perhaps even intensive care.

Anyone experiencing severe or unusual headaches should see a doctor as soon as possible. Also, anyone who has been in an area where the virus has been identified and who experiences high fever, muscle weakness, confusion or severe headaches should see a doctor immediately.

How do people catch this disease?

Eastern Equine Encephalitis cannot be passed from person to person. The only way to get the virus is from the bite of an infected mosquito that has the virus in their blood. The mosquito can spread the virus to birds, animals or people, when it bites during feeding. Transmission to people and mammals is relatively rare, but is very serious when it occurs. There were only 182 confirmed cases in the United States during the 36 year period from 1964 – 2000. There have only been 8 confirmed cases in South Carolina during that same time frame.

How can we prevent this illness?

There are many things that you can do to help. Key is reducing the breeding grounds for mosquitoes. Be sure to empty any and all containers that hold standing water, and keep them emptied. You can reduce the possibility of this infection even more by taking a few other simple steps:

  • Wear long sleeved shirts and long pants when you go outside
  • Stay inside at mosquito feeding time; dawn, dusk and early evening
  • Spray clothing with a mosquito repellant containing DEET
  • Apply insect repellant containing DEET to exposed skin
  • There is a vaccine available for horses. For more information, contact your veterinarian

Mosquito control is key in reducing the impact of Eastern Equine Encephalitis. In South Carolina mosquito control is a public service provided by local county governments. To find out the plans for your community, contact the Berkeley ((843) 719-4052), Charleston (843-202-7880), or Dorchester (832-0005 or 563-0005) County Mosquito Abatement Programs.