The woman is a resident of New Haven County and is between 50 and 59 years old, DPH said.
She became ill during the third week of July with West Nile fever and has since recovered.
"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 Dr. Manisha Juthani. “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."
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 that 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. Of those, about one of 10 are severe and can be fatal, officials said.
People over the age of 60 are at highest risk of serious illness.
For information on West Nile virus and how to prevent mosquito bites, visit the Connecticut Mosquito Management Program Web site at www.ct.gov/mosquito.
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