The Jefferson County Health Department found a sample of adult mosquitoes in unincorporated Fenton that tested positive for West Nile Virus – the second positive sample in Jefferson County this season, the agency reported.
The sample was collected Sept. 23.
The first positive sample was found in Hillsboro on Sept. 5, the Health Department reported.
Judy Tufts, the Health Department’s emergency response supervisor, said the mosquito season starts once temperatures rise above 70 degrees and stay there. She said the season normally starts around late May and early June and goes to early October.
The mosquitoes that tested positive for the virus were found in surveillance traps the Health Department set up, Tufts said.
She said there are 100 sites around the county with surveillance traps.
Emergency response vector technician Scott Darrough said residents should continue taking measures to avoid mosquito bites and to prevent, or at least minimize, population growth in mosquitoes.
Some protection measures include using insect repellent containing 20-50 percent DEET or Picaridin, wearing light-colored clothing and removing standing water sources that can be sites for mosquitoes to lay eggs in, such as old tires, cans, buckets, flower pots or pools.