Eastern Equine Encephalitis

Eastern Equine Encephalitis (EEE) is a rare but serious disease caused by a virus that is spread by mosquitoes. 

EEE is a type of sickness that can affect horses and humans. It is mainly found in certain parts of the United States. The virus that causes EEE is carried by mosquitoes. When a mosquito bites an infected bird, it can become infected with the virus. Then, if that mosquito bites a horse or a person, it can pass on the virus and make them sick.

In humans, EEE can cause two different types of infections. The first type is like having the flu, with symptoms such as fever, headache, muscle pain, and joint pain. Most people with this type of infection get better on their own.

The second type of infection is more severe and can affect the brain. This can lead to problems like seizures, confusion, and even a coma. It is very important to get medical help if someone has these symptoms because it can be life-threatening.

To prevent EEE, it's essential to take steps to avoid mosquito bites. This includes using bug repellents, wearing long sleeves and pants when outside, and staying indoors during times when mosquitoes are most active, like dawn and dusk. It's also important to get rid of standing water around your home where mosquitoes can breed.

While EEE is rare, it's still important to be aware of it and take precautions if you live in or visit areas where it has been found. Remember, if you have any concerns or think you might have EEE, talk to a doctor who can provide the right guidance and treatment.

  • What is Eastern Equine Encephalits?

    Eastern Equine Encephalitis (EEE), or "Triple E," is a rare but severe mosquito-borne viral disease primarily affecting horses and humans. The name "Eastern Equine Encephalitis" comes from the fact that horses are particularly susceptible to the virus and often suffer severe illness or death when infected. 

  • How is Eastern Equine Encephalitis spread?

    EEE virus is primarily transmitted through the bite of infected mosquitoes. 

  • What are the symptoms of Eastern Equine Encephalitis?

    Most people infected with EEE do not develop symptoms. For those who develop symptoms, the time from infected mosquito bite to onset of illness (incubation period) ranges from 4 to 10 days.

    The illness can start with general flu-like symptoms such as fever, headache, muscle pain, and joint pain. However, the disease can progress to a more severe form, causing inflammation of the brain (encephalitis), which can lead to neurological symptoms, seizures, coma, and, in some cases, death. Severe EEE has a high mortality rate, with approximately one-third of infected individuals dying from the disease, and many survivors experiencing long-term neurological complications.

  • What is the treatment for Eastern Equine Encephalitis?

    There is currently no specific antiviral treatment for EEE in humans, and supportive care is the main approach to managing the disease. Prevention measures, such as mosquito control, wearing protective clothing, and using mosquito repellents, are essential to reduce the risk of infection. Vaccines are available for horses, but there is no approved vaccine for humans.

  • What can be done to prevent the spread of Eastern Equine Encephalitis?

    Preventing the spread of Eastern Equine Encephalitis (EEE) among humans primarily involves taking measures to reduce mosquito populations and minimize exposure to mosquito bites. Here are some key preventive measures:

    1. Mosquito Control: Reducing mosquito populations is crucial in preventing the transmission of EEE. This can be achieved through various methods such as:

      • Eliminating or treating standing water sources where mosquitoes breed, such as stagnant pools, buckets, and flower pots.
      • Applying larvicides to kill mosquito larvae in areas of standing water that cannot be drained.
      • Using insecticides or employing professional mosquito control services to target adult mosquitoes.
    2. Personal Protection: Minimizing exposure to mosquito bites is essential to prevent EEE. Individuals should:

      • Use mosquito repellents containing DEET, picaridin, or oil of lemon eucalyptus on exposed skin.
      • Wear long sleeves, long pants, and socks to cover the skin, especially during peak mosquito activity times.
      • Avoid outdoor activities during dusk and dawn when mosquitoes are most active.
    3. Environmental Modification: Modifying the environment can help reduce mosquito breeding sites and their access to humans:

      • Keep windows and doors screened to prevent mosquitoes from entering living areas.
      • Repair or replace damaged screens on windows and doors.
      • Install mosquito nets or bed nets over sleeping areas, particularly for infants and young children.
    4. Awareness and Education: Public education about EEE and mosquito-borne diseases is important for individuals to understand the risks and take necessary precautions. This includes:

      • Disseminating information through local health departments, schools, community organizations, and media outlets.
      • Providing guidance on mosquito bite prevention strategies and raising awareness about EEE symptoms and the importance of seeking medical attention promptly.
    5. Animal Vaccination: Vaccinating horses against EEE can help reduce the risk of transmission to humans and prevent severe illness in equine populations.

    It's worth noting that EEE is relatively rare, and the risk of infection varies by geographic location. However, implementing these preventive measures can help mitigate the spread of the disease and minimize the potential impact on affected communities.

  • How many cases of Eastern Equine Encephalitis are reported in Georgia and the US each year?

    The Georgia Department of Public Health tracks and monitors cases of mosquito diseases, including Eastern Equine Encephalitis, through passive surveillance systems which relies on healthcare providers to submit laboratory results and medical records for review. 

    Georgia Data

    From the years 2018 to 2022, a total of 4 cases of Eastern Equine Encephalitis were reported in Georgia residents. 

    National Data

    Eastern Equine Encephalitis Virus - Data & Maps (CDC) [external link]

    Case Surveillance

    What is Case Surveillance? (CSTE) [external link]

    NOTE: Disease surveillance systems primarily count cases based on the patient's residential location rather than the specific location of exposure.


Page last updated 07/05/2023