Press Releases


DPH Advises Residents to Take Extra Precautions to Prevent Contracting Eastern Equine Encephalitis

Residents are Advised to Protect Themselves and Their Children by Avoiding Outdoor Activity from Dusk to Dawn, When Mosquitoes are Most Active

The Connecticut Department of Public Health today is urging residents to continue personal preventive measures to avoid mosquito bites and reduce the chance of contracting eastern equine encephalitis (EEE) virus. Residents are advised to protect themselves and their children by minimizing outdoor activity from dusk to dawn, when mosquitoes are most active.  The mosquitoes that carry the virus are active until the first heavy frost.

The EEE virus has been identified in mosquitoes in 12 towns and in horses in two other towns.  Towns where mosquitoes have tested positive for EEE include: Chester, Haddam, Hampton, Groton, Killingworth, Ledyard, Madison, North Stonington, Plainfield, Shelton, Stonington, and Voluntown.  Horses have tested positive for EEE virus in Colchester and Columbia this season, and the virus has been detected in a flock of wild pheasants.  Other states throughout the Northeast are also experiencing an active season for EEE.  In addition to the virus being found in mosquitoes, human cases of EEE infection, including fatalities, have been identified this year in Massachusetts, Rhode Island, and New Jersey.  No human cases of EEE have been identified in Connecticut so far this year.

“Connecticut residents, especially those in the eastern part of the state, should continue to take mosquitoes seriously and take routine precautions to prevent mosquito bites.” cautioned DPH Commissioner Renée Coleman Mitchell. “The mosquitoes that carry the virus are active until the first heavy frost.”

The DPH advises against unnecessary trips into mosquito breeding grounds and marshes as the mosquitoes that transmit EEE virus are associated with freshwater swamps and are most active at dusk and dawn.  Overnight camping or other substantial outdoor exposure in freshwater swamps in Connecticut should be avoided.  Even though the temperatures are getting cooler, it is important to remember mosquito season is not over and residents should continue to take measures to prevent mosquito bites, including wearing protective clothing and using repellents.

Although EEE-infected mosquitoes continue to be detected in the southeastern corner of the State, the numbers are beginning to decline and we are not experiencing the excessively high levels of activity seen in Massachusetts.  There are currently no plans to implement widespread pesticide sprays in the State. 

The EEE virus is a rare but serious disease transmitted by mosquitoes which acquire the virus by feeding on wild birds. The virus cannot be spread person-to-person or from horses to humans. On average, there are 6 human cases of EEE reported each year in the United States. Symptoms include fever, headache, stiff neck, and reduced consciousness. Individuals experiencing these symptoms should seek medical care immediately. Approximately 25-50% of cases are fatal and one-half of survivors suffer permanent neurological damage. In Connecticut, the first locally-acquired human case occurred in the fall of 2013. That patient died from the infection. 
Personal precautions to avoid mosquito bites include: 

  • Be sure door and window screens are tight fitting and in good repair.
  • While outdoors, wear shoes, socks, long pants, and long-sleeved shirts. Clothing should be light colored and made of tightly woven materials that keep mosquitoes away from the skin.
  • Consider using mosquito repellent when it is necessary to be outdoors and always use them according to label instructions. The most effective repellents contain DEET or Picaridin. 
  • Limit infants’ and children’s exposure to mosquitos and dress them in protective clothing when outdoors. 
  • Use mosquito netting if sleeping outdoors.

    For information on what can be done to prevent getting bitten by mosquitoes and the latest mosquito test results and human infections, visit the Connecticut Mosquito Management Program web site at

    For more information about EEE prevention visit the CDC website