Mosquitos in Darien has tested positive for Eastern Equine Encephalitis (EEE), Darien’s Department of Health announced Thursday. This is the first time mosquitos in Darien have tested positive for EEE since October 2009. The State of Connecticut’s Mosquito Management Program said mosquitos trapped in Darien on Oct. 7, tested positive for Eastern Equine Encephalitis (EEE).

The Connecticut Agricultural Experimental Station will continue to monitor the situation in Darien. Mosquitos will be trapped weekly throughout October until no virus is detected or mosquitos are no longer seen in the area. Mosquito breeding season is over and the overall number of mosquitos continues to decrease. The risk of transmission of mosquito-borne diseases is low, but is not yet zero.

The 10-day forecast for Darien is for mild weather. However, residents should continue to take precautionary measures that prevent mosquito bites — especially on warmer days. The Health Department recommends residents:

● Minimize outdoor activities the hour before and after sunset, especially when temperatures remain above 50 degrees in the evening

● When outdoors use approved mosquito repellent and wear long sleeves and pants

● Ensure window screens and door screens are intact

Risk for mosquito-borne disease is virtually eliminated by the first local hard frost which kills most remaining adult mosquitoes. A hard, or killing frost, is defined meteorologically as two consecutive hours of temperatures below 28 degrees Fahrenheit or three hours below 32 degrees. This will occur at different times for different communities, and there may even be variation within communities based on local geography.

Although mosquitoes are not killed until a hard frost occurs, they are extremely unlikely to be active when temperatures fall below 50 degrees in the evening, and communities may wish to consider this information when making decisions about scheduling or cancelling planned outdoor events late in the season.

No human cases of EE have been reported in the Darien area.

School response

Darien’s Schools Superintendent Alan Addley informed the district’s parents following the release and advised that some evening activities’ schedules will be modified. Parents are also able to elminate outdoor recess if they choose to. See the full letter below:

Good Evening Parents and Guardians,

This is another update pertaining to Eastern Equine Encephalitis (EEE). Yesterday, Darien’s Health Department announced mosquitos trapped in Darien on October 7, 2019 tested positive for EEE. This is the first time in a decade that mosquitos in Darien have tested positive for EEE.

State and local health officials still emphasize there is minimal risk but continue to recommend personal protective measures be taken during outdoor evening events. There still has been no recommendation to cancel outdoor activities or change school schedules.

Nonetheless, given this new development, and in an abundance of caution, the district will be modifying the start times of some of its evening outdoor activities. The modification to evening activity schedules will be communicated by school administration. Elementary and middle school students still have outdoor recess during the school day. However, should you desire your child not to participate in outdoor recess, please notify your child’s classroom teacher (elementary school) or team leader/flex teacher (middle school) via email tomorrow morning and the school will include your child in alternate indoor recess activities. These practices across the district will remain in place until we experience a hard local frost.

Thank you for your understanding as we respond to this unique situation. As previously communicated, we continue to be in close communication with local and state health officials and will update you with any changes in position going forward. Thankfully, mosquito season is nearly over!


Alan Addley, Ed.D.

Superintendent of Schools