Press Releases

09/16/2019

DPH Announces First Human Case of Eastern Equine Encephalitis Identified In Connecticut This Season

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

Department of Public Health (DPH) Commissioner Renée D. Coleman-Mitchell today is announcing that an adult resident of the town of East Lyme has tested positive for Eastern Equine Encephalitis (EEE). This is the first human case of EEE identified in Connecticut this season. The patient became ill during the last week of August with encephalitis and remains hospitalized. Laboratory tests, which were completed today at the Centers for Disease Control and Prevention (CDC) Laboratory in Ft. Collins, Colorado, confirmed the presence of antibodies to the virus that causes EEE.  

“EEE is a rare but serious and potentially fatal disease that can affect people of all ages,” cautioned DPH Commissioner Renée Coleman Mitchell.  “Using insect repellent, covering bare skin and avoiding being outdoors from dusk to dawn are effective ways to help keep you from being bitten by mosquitoes.” 

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, there have been a total of eight human cases of EEE infection in Massachusetts and one human case in Rhode Island, with one case in each state resulting in a fatality.

“This is the second human case of EEE ever reported in Connecticut,” said Dr. Matthew Cartter, Director of Infectious Diseases for the DPH.  “The first human case of EEE reported in Connecticut occurred in the fall of 2013.”
Link to information on 2013 case: 
https://portal.ct.gov/-/media/Departments-and-Agencies/DPH/dph/infectious_diseases/CTEPINEWS/Vol34No3pdf.pdf?la=en

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 declining and we are not experiencing the excessively high levels of activity seen in Massachusetts. There are currently no plans to implement widespread aerial pesticide spraying in the State.  

Severe cases of EEE virus infection (involving encephalitis, an inflammation of the brain) begin with the sudden onset of headache, high fever, chills, and vomiting. The illness may then progress into disorientation, seizures, and coma.  Approximately a third of patients who develop EEE die, and many of those who survive have mild to severe brain damage.  There is no specific treatment for EEE.  Antibiotics are not effective against viruses, and no effective anti-viral drugs have been discovered.  Severe illnesses are treated by supportive therapy which may include hospitalization, respiratory support, IV fluids, and prevention of other infections.  It takes 4 to 10 days after the bite of an infected mosquito to develop symptoms of EEE.

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