Press Releases

09/30/2019

DPH Announces Death of the Third Person Diagnosed With Eastern Equine Encephalitis (EEE) This Year and the Diagnosis of EEE in A Fourth Person Who Remains Hospitalized After Five Weeks

Residents, Especially Those in the Southeastern Part of the State from the Lower Connecticut River Valley to the Rhode Island Border, are Advised to Protect Themselves and Their Children by Taking Personal Precautions to Prevent Mosquito Bites Until the First Hard Frost of the Fall.  Consideration Should Also be given toMinimizing Outdoor Activity from Dusk to Dawn, When Mosquitoes Are Most Active

Department of Public Health (DPH) State Epidemiologist Dr. Matthew Cartter today is announcing that an East Haddam resident who died during the third week of September was confirmed today to have had Eastern Equine Encephalitis (EEE) by the Centers for Disease Control and Prevention (CDC).  This person, who is between 60 and 69 years of age, became ill during the second week of September 2019.

The Department also learned today that the CDC has also confirmed EEE to be the cause of illness for a resident of Colchester who became ill during the third week of August and who remains hospitalized.  This person is between 40 and 49 years of age.

“Sadly, this has been an unprecedented year for EEE activity in Connecticut,” said Dr. Matthew Cartter, the DPH State Epidemiologist.  “Before this year we have had only one human case of EEE in Connecticut, and that was in 2013.  ”  

“We have had four human cases of EEE, three of which were fatal.  All four were most likely exposed to infected mosquitoes sometime between August 11, 2019 and September 8, 2019, which was the peak period of mosquito activity in Connecticut” said Dr. Cartter.  “All four residents live in a part of eastern Connecticut where EEE activity has not been a problem before this summer.”

“In the southeastern part of the state from the lower Connecticut River valley to the Rhode Island border region, the risk of becoming ill as a result of being bitten by a mosquito infected with EEE virus is low but not zero;” cautioned Dr. Cartter.  “The forecast is for cooler weather to arrive by the weekend, but the risk of EEE will not be gone until the first hard frost.”

States throughout the Northeast are also experiencing an active season for EEE.  In addition to the virus being found in mosquitoes, there have been a total of 12 human cases of EEE infection in Massachusetts, including three fatalities, and three human cases in Rhode Island, including 1 fatality.  Although EEE-infected mosquitoes continue to be detected in the southeastern corner of Connecticut, the numbers are declining and we are not experiencing the excessively high levels of activity seen in Massachusetts. There are no plans to implement widespread pesticide sprays in the State.  Both Massachusetts and Rhode Island have completed aerial spraying for mosquitoes for the season.  

Yesterday, the Connecticut Agricultural Experiment Station identified EEE virus in mosquitos that were trapped last week in its Bethany and Middlefield sites.  Residents of these towns are advised to protect themselves and their children by taking personal precautions to prevent mosquito bites.  Consideration should also be given to minimizing outdoor activity from dusk to dawn, when mosquitoes are most active.  

Most persons infected with EEE have no apparent illness, however some can be very ill. Severe cases of EEE (involving encephalitis, an inflammation of the brain) begin with the sudden onset of headache, high fever, chills, and vomiting 4 to 10 days after a mosquito bite.  The illness may then progress to disorientation, seizures, or coma.

EEE is one of the most severe mosquito-transmitted diseases in the U.S. About one-third of people with EEE die from the disease and there is significant brain damage in most survivors.  While there is a vaccine for horses, there is no vaccine for people.

DPH continues to ask Connecticut residents not to take unnecessary trips into marshes and freshwater swamps as these are typically breeding grounds for mosquitoes that transmit the EEE virus, with such mosquitoes being 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, mosquitoes continue to be active until the first heavy frost and residents should continue to take measures to prevent mosquito bites.

EEE virus is not the only vector-borne disease in Connecticut that can cause encephalitis.  This year, we have had one case of encephalitis caused by West Nile virus.  Powassan virus, which is  relatively new in Connecticut and can be transmitted by the bite of the black-legged tick, can also cause encephalitis.  This year, we have had four human cases of Powassan virus infection, one of which ended in a fatality.

Connecticut Mosquito Management program

The management of mosquitoes in Connecticut is a collaborative effort involving the Department of Energy and Environmental Protection (DEEP), the Connecticut Agricultural Experiment Station (CAES) and the Department of Public Health (DPH), together with the Department of Agriculture and the Department of Pathobiology at the University of Connecticut (UCONN). These agencies are responsible for monitoring and managing the state’s mosquito population levels to reduce the potential public health threat of mosquito-borne diseases.

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 https://portal.ct.gov/mosquito

For more information about EEE prevention, please visit the CDC website:
https://www.cdc.gov/easternequineencephalitis/gen/pre.html