Denton’s first mosquito trap to turn up positive for West Nile virus this year was found at the Robson Ranch community on the southwest side of the city.
Ken Banks, the city’s director of environmental services, said the trap was set Oct. 1 and the results came back from the state’s laboratory late Tuesday.
The city’s response plan has not changed from Level 4, which steps up trapping and public notices but doesn’t call for any targeted ground-level spraying, Banks said.
He has been in touch with Robson Ranch officials about reminding residents to take extra precautions, including making efforts to drain standing water and using larvacide to treat water that can’t be drained.
While the early signs this year were for another bad year, as last year was, the season turned out to be mild for Denton, Banks said.
“I thought we might get to the end of the season without a positive mosquito pool,” he said.
The city’s first and only human case so far was identified in July. The city adjusted its trapping to cover the neighborhood around that particular case, but no mosquito pools ever turned up positive there, Banks said.
Moreover, the cooler weather that has followed several cold fronts and rain since the beginning of October should slow the mosquitoes down, he said. The type of mosquito that carries the West Nile virus locally doesn’t breed as well in such weather conditions.
Banks expects the city to continue trapping through at least the end of the month.
The decision to end trapping depends largely on the weather, he said.
Denton contracts with the University of North Texas for the service.
Many of the positive mosquito pools that have been found in Denton County have been in the southern part of the county, including the cities of Flower Mound, Lewisville and Highland Village.
One positive pool was found near Meadowview Park in Corinth in August.
Sarah McKinney, spokeswoman for the Denton County Health Department, said it was surprising to hear of a positive pool at this time.
“We didn’t expect to see them so late in the year. We’ve had sort of a resurgence in the last few weeks,” she said.
McKinney said the county was planning to stop its own testing and trapping Sept. 26, the week the first positive pool report was received from the state.
McKinney said that typically when the weather starts cooling, there will be a drop in mosquitoes, but it’s difficult to compare testing data for years past because the county was not doing testing then and positive pools of mosquitoes could have gone unnoticed.
“We’re kind of establishing a baseline with our testing,” she said.
McKinney said health officials are going to extend testing through Oct. 24.
PEGGY HEINKEL-WOLFE can be reached at 940-566-6881 and via Twitter at @phwolfeDRC.
BJ LEWIS can be reached at 940-566-6875 and via Twitter at @BjlewisDRC.