SHELTON — Mosquitoes in Shelton have recently tested positive for the West Nile Virus, the Naugatuck Valley Health District announced Tuesday (Sept. 1).

The mosquitoes were collected at a trapping station on Aug. 25 in the area of Shelton Avenue, according to the NVHD.

The station is monitored by the Connecticut Agricultural Experiment Station, part of the state’s Mosquito Management Program, according to the announcement.

The detection of WNV in mosquitoes does not mean that all mosquitoes are infected or that a human case has occurred locally,” according to the NVHD announcement. “However, it confirms local virus activity and reinforces the importance of preventing mosquito bites.”

State officials have reported increasing West Nile Virus activity, particularly in Fairfield and New Haven counties, with the risk expected to continue through September.

Mosquito trapping is conducted daily from June through October at 108 permanent locations throughout the state. The Shelton trap site is the only site in the NVHD jurisdiction.

“Residents throughout the Naugatuck Valley should take simple precautions to protect themselves and their families from mosquito bites,” said NVHD Health Director Jessica Kristy. “This finding is an important reminder that West Nile virus is circulating in our area, even as summer comes to an end.”

The warm weather, high humidity, and frequent rainfall have created ideal conditions that are conducive to the spread of West Nile Virus infected mosquitoes. The species of mosquito that tested positive for West Nile Virus, Culex pipiens, can be found in a wide variety of places, such as old tires, stagnant pools of ground water, artificial containers, or catch basins, according to the NVHD announcement.

NVHD recommends that residents:

  • Minimize time spent outdoors between dusk and dawn when mosquitoes are most active.
  • When it is necessary to be outdoors, use mosquito repellents containing an EPA-registered active ingredient, including DEET, Picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol (PMD), or 2-undecanone. EPA registration of skin-applied repellent products indicates that they have been evaluated and approved for human safety and effectiveness when applied according to instructions on the label.
  • Wear shoes, socks, long pants, and a long-sleeved shirt when outdoors for long periods of time, or when mosquitoes are more active. Clothing should be light-colored, loose-fitting, and made of tightly woven materials that keep mosquitoes away from the skin.
  • Wear clothing and gear treated with permethrin. Permethrin is an insecticide that kills or repels mosquitoes and ticks.
  • Be sure door and window screens are tight-fitting and in good repair.
  • When sleeping outdoors, use tents or mosquito netting in an unscreened structure. Treat camping gear with permethrin when possible.
  • Cover strollers and baby carriers with mosquito nets when outside.
  • Replace your outdoor lights with yellow “bug” lights, which tend to attract fewer mosquitoes than ordinary lights. The yellow lights are NOT repellents, however.

Additionally, NVHD recommends the following steps to remove mosquito habitats:

  • Eliminate standing water in rain gutters, old tires, buckets, plastic covers, toys, tires, or any other container where mosquitoes can breed.
  • Turn over plastic wading pools, wheelbarrows, etc.
  • Empty and change the water in bird baths, fountains, rain barrels, and potted plant trays at least once a week to destroy potential mosquito habitats.
  • Keep swimming pool water treated and circulating.
  • Use landscaping to eliminate standing water on your property.

Click here to learn more about the State of Connecticut Mosquito Management Program.

Mosquito traps are set and attended by CAES staff about every 10 days on a regular rotation, and then at least once a week after detection of the virus, in order to assess potential public health risks. Mosquitoes are grouped (pooled) for testing according to species, collection site, and date.

On Aug. 27, 2026, CT DPH announced the first human case of WNV-associated illness in a Connecticut resident this season. The case is a male resident of Middlesex County and is between 30 and 39 years of age.

Towns with West Nile virus (WNV) Infected Mosquitoes this week: Bethel, Darien, Hamden, New Haven, Orange, Shelton, Stamford, Trumbull, West Hartford, Weston, Westport, Woodbridge


Towns with West Nile virus (WNV) Infected Mosquitoes in 2026: Bethel, Branford, Bridgeport, Cheshire, Cromwell, Danbury, Darien, East Haven, Fairfield, Greenwich, Haddam, Hamden, Killingworth, Manchester, Meriden, Middlefield, Milford, Montville, New Britain, New Canaan, New Haven, North Branford, North Haven, North Stonington, Norwalk, Old Lyme, Orange, Shelton, South Windsor, Stonington, Stamford, Stratford, Trumbull, West Hartford, West Haven, Weston, Westport, Woodbridge

Counties with West Nile virus (WNV) Human Cases: Fairfield = 1, Middlesex = 1

For more information, click here.