How St. Louis County combats rising mosquito numbers

3 months ago 3

ST. LOUIS COUNTY, Mo. – Our weather has been the perfect storm for rising mosquito numbers this summer. The employees at St. Louis County Public Health Vector Borne Disease Prevention are in full force, working hard to keep numbers in control.

“We always seem to be getting this right amount of precipitation to keep life cycles going, but not heavy rainstorms that might flush mosquito eggs away from where they were laid or we are not getting enough dry weather to completely dry everything up,” Amanda Brzozowski, a senior epidemiologist with the St. Louis County Department of Public Health, said.

She says hot and dry conditions are typically when we see the most West Nile virus, but humidity doesn’t hurt.

“What the virus amplifies first in mosquitoes and birds and then in humans after that. So that’s why control activities will first identify West Nile virus positive mosquitoes and then a human case will typically come shortly after that,” she said.

A two-pronged approach is used to try to control the problem. They get the biggest bang for their buck by larviciding, which is the control of larval mosquitoes. They also do adult spraying with their trucks. The time at which they spray depends on what type of mosquitoes they are trying to eliminate