The Connecticut Mosquito Management Program announced Aug. 8 that mosquitoes trapped in nine towns from July 25 to Aug. 1 tested positive for West Nile virus. These results represent the first positive mosquitoes identified in New Canaan, Danbury, Darien, Easton, Fairfield, Hamden, Litchfield, Stratford and Woodbridge by the Connecticut Agricultural Experiment Station (CAES) this year.

In 2011, WNV-positive mosquitoes have been trapped in 15 municipalities: Bridgeport; Danbury; Darien; Easton; Fairfield; Greenwich; Hamden; Litchfield; New Britain; New Canaan; Orange; Stamford; Stratford; Westport; and Woodbridge. There have been no reports of Connecticut residents contracting illnesses related to WNV infections this year. In 2010, WNV-positive mosquitoes were trapped in 24 municipalities with 11 reported human cases.

"As expected, we continue to find mosquitoes infected with West Nile virus in more locations in lower Fairfield County and are now seeing an expansion into other areas of Connecticut," said Dr. Theodore G. Andreadis, chief medical entomologist, CAES, said in a press release. "Over the next few weeks and into early fall, we expect to see further build-up of West Nile virus with increased risk for human infection throughout the state, especially in densely populated communities."

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The state uses a network of 91 mosquito-trapping stations in 72 municipalities maintained by the CAES to monitor WNV activity. Mosquito traps are set Monday through Thursday nights, and conducted at each site every 10 days on a rotating basis. Mosquitoes are grouped for testing according to species, collection site and date. Each pool is tested for the presence of viruses of public health importance. Positive findings are reported to local health departments, in press releases, and on the CAES website at

In response to the latest West Nile findings, beginning this week, The Town of New Canaan will treat the catch basins to help control the breeding of mosquitoes which may be carriers of the West Nile Virus. The EPA registered treatment being used is VectoLex CG.

According to the New Canaan Health Department, the easiest and best way to avoid WNV is to prevent mosquito bites.

- When you are outdoors, use insect repellent containing DEET or other EPA-registered active ingredients. Follow the directions on the package.

- Many mosquitoes are most active at dusk and dawn. Be sure to use insect repellent and wear long sleeves and pants at these times or consider staying indoors during these hours.

- Make sure you have good screens on your windows and doors to keep mosquitoes out.

- Get rid of mosquito breeding sites by emptying standing water from flower pots, buckets and barrels. Change the water in pet dishes and replace the water in bird baths weekly. Drill holes in tire swings so water drains out. Keep child wading pools empty and on their sides when they aren't being used.

According to the Health Department, West Nile Virus is generally a self-limited disease and many people who become infected do not realize it because it can run a mild course. More serious cases can occur in immune compromised people with AIDS, auto immune disorders or those who are undergoing chemotherapy. Persons in these risk categories should be especially careful to follow the prevention strategies outlined on the web sites below.

For information about West Nile virus and how to prevent getting bitten by mosquitoes, visit the Connecticut Mosquito Management Program website at or