State of Connecticut Mosquito Management Program

Press Releases

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08/18/2023

DPH announces first case of West Nile virus infection this year

CONTACT:    Chris Boyle—Director of Communications
860-706-9654 – christopher.boyle@ct.gov

HARTFORD, Conn.– The Connecticut Department of Public Health (DPH) today announced that a Connecticut resident has tested positive for West Nile virus (WNV) infection. This is the first human case of WNV-associated illness identified in Connecticut this season.

The female is a resident of New Haven County and is between 50-59 years of age. She became ill during the third week of July with West Nile fever and has since recovered. Laboratory tests confirmed the presence of antibodies to WNV.

"As we approach the end of summer and continue to enjoy time outdoors with family, friends, and neighbors, it is important to prevent mosquito bites to reduce your risk of exposure to West Nile virus infection," said DPH Commissioner Manisha Juthani, MD.  “Using insect repellent, covering bare skin, and avoiding being outdoors during the hours of dusk and dawn are effective ways to help keep you from being bitten by mosquitoes."

"The mosquitoes that carry West Nile virus are most abundant in urban and suburban areas and are most active between dusk and dawn. We anticipate continued risk for human infection until mosquito activity subsides in October,” added Philip Armstrong, ScD, medical entomologist at the Connecticut Agricultural Experiment Station.

West Nile virus has been detected in Connecticut every year since 1999 and is the most prevalent mosquito-borne disease in the US. Most people infected with WNV do not develop symptoms. About one in five people who are infected develop West Nile fever, an illness which includes a fever and other symptoms such as body aches, joint pain, headache, or a rash. About one out of 150 infected people develop a severe illness affecting the central nervous system. About one out of 10 cases of severe illness are fatal. People over the age of 60 are at highest risk of serious illness.

Tips for reducing mosquitoes around homes

Mosquitoes require water for reproduction. The following are measures that can help reduce mosquitoes:

  • Eliminate standing water suitable for mosquitoes. Dispose of water-holding containers, such as ceramic pots, used tires, and tire swings.
  • Drill holes in the bottom of containers such as those used for recycling.
  • Clean clogged roof gutters.
  • Turn over objects that may trap water when not in use, such as wading pools and wheelbarrows.
  • Change water in bird baths on a weekly basis.
  • Clean and chlorinate swimming pools. When pools are not in use, use pool covers and drain when necessary.

Tips for avoiding mosquito bites when outdoors

Mosquitoes require a blood meal for reproduction. The following are measures that can help reduce bites from mosquitoes that feed on people:

  • Minimize outdoor activities at dusk and dawn when mosquitoes are most active.
  • Wear shoes, socks, long pants, and long-sleeved shirts. Clothing material should be tightly woven and loose fitting.
  • Use mosquito netting when sleeping outdoors.
  • Consider the use of CDC-recommended mosquito repellents, containing DEET, picaridin, oil of lemon eucalyptus, IR3535, or 2-undecanone, and apply according to directions, when it is necessary to be outdoors.
  • When using DEET, use the lowest concentration effective for the time spent outdoors (for example, 6 percent lasts approximately two hours and 20% for four hours) and wash treated skin when returning indoors. Do not apply under clothing, to wounds or irritated skin, the hands of children, or to infants less than two months old.
  • Be sure door and window screens are tight fitting and in good repair to avoid mosquito bites when indoors.

The State of Connecticut Mosquito Management Program is a collaborative effort involving the Department of Energy and Environmental Protection, the Connecticut Agricultural Experiment Station, the Department of Public Health, the Department of Agriculture, and the University of Connecticut Department of Pathobiology and Veterinary Science. These agencies are responsible for monitoring the potential public health threat of mosquito-borne diseases.

The CAES maintains a network of 108 mosquito-trapping stations in 87 municipalities throughout the state. Mosquito traps are set Monday through Thursday nights at each site every ten days on a rotating basis. Mosquitoes are grouped (pooled) for testing according to species, collection site, and date. Positive findings are reported to local health departments and on the CAES website.

For information on West Nile virus and how to prevent mosquito bites, visit the Connecticut Mosquito Management Program website.