West Nile Virus Found In Buffalo Grove Mosquitoes

The Lake County Health Department reported Thursday that a pool of mosquitoes in Buffalo Grove tested positive for West Nile virus earlier this month.

“Since West Nile first manifested itself, we’ve had positives almost every year,” Brian Sheehan, Buffalo Grove’s health officer, said.

The pool that tested positive this year was located near the , he said. It was the first batch to test positive this summer in Lake County.

The sample was collected Aug. 4. A preliminary test came back negative, but a routine follow-up test detected infected mosquitoes, he said.

While mosquito abatement efforts are made, wind and temperature conditions have to be right for spraying to be effective, Sheehan said.

“When the temperature drops below 60, they can go out and spray, but it’s like spitting in the wind, so to speak,” he said.

Spraying, which is done by Clarke in Lake County and in Cook County by the Northwest Mosquito Abatement District, takes place when the mosquito population reaches nuisance level, as determined by the number found in traps, or when West Nile virus is detected, Sheehan said.

The village was sprayed for mosquitoes on Aug. 10, before officials learned that infected mosquitoes had been found, he said. The timing of that application is likely why there were not enough mosquitoes to test on Aug. 11, when traps were again checked.

Mosquito pools were tested again last week, Sheehan said. Initial test results found no West Nile-infected mosquitoes, which he hopes the second, more sensitive test, will confirm. He said he was still awaiting test results Friday afternoon.

While conditions must be right for a village-wide spraying to take place, Buffalo Grove spot-treats areas in advance of community-wide events, such as July 4 fireworks and Buffalo Grove Days, Sheehan said.

The village campus will be sprayed in the middle of next week in preparation for the thousands of people expected at the five-day Buffalo Grove Days festival, he said.

The Lake County Health Department provided tips for preventing mosquitoes from breed and avoiding mosquito bites in the announcement it posted Thursday on this site.