FENTON, Mo. – The Jefferson County Health Department found adult mosquitoes that tested positive for the West Nile Virus on September 23. This is the second positive result of the month after the virus was also found in Hillsboro.
The virus has not been reported in humans.
James Sayers, vector control program supervisor for St. Louis County, said even though it’s rare for humans to contract West Nile, people still need to take precaution.
“Even though we are getting into fall and it can be cooler out, people need to be aware,” he said. “They need to check their property for standing water.”
The Jefferson County Health Department’s Mosquito Control and Surveillance program is checking in on the pesky bugs.
“When you see our trucks rolling down the street that’s an indicator that we have found high numbers of Culex mosquitos or those mosquitos have tested positive for West Nile,” Sayers said.
They initiate spray application which specifically targets the Culex mosquito, the breed that carries the virus.
Heavy rain earlier in the year brought optimal breeding grounds for mosquitoes but surprisingly fewer of the West Nile carrying breed.
“With all the rain we’ve had this year, we have seen a lot of different types of mosquitos. A lot of the nuisance mosquitos. On the other hand, when we get a lot of rain, we tend to see fewer Culex,” Sayer said.
The Culex breed in areas where rain drains and washes the larva away. The weather will continue to help drop mosquito numbers but there is still a wait and see approach. As the temperatures drop, the mosquito activity will drop a little bit but we will see mosquitos until it gets to freezing.
Before it drops to freezing, make sure you still have your bug repellent handy. Be cautious: not all sprays are equal. It’s recommended that you have spray that has at least 25 percent DEET.