BRENTWOOD -- Pesticide fogging trucks will roll through parts of Brentwood Thursday night in an effort to control mosquitoes and prevent the spread of West Nile virus, officials said.
Dead birds found to have West Nile virus were recently discovered in Brentwood, Pleasant Hill and Knightsen. Mosquitoes with the virus found in Brentwood on July 10 and again Monday, according to the Contra Costa Mosquito and Vector Control District.
Fogging trucks will work between 8:30 and 11 p.m., depending on weather, to cover an area bordered on the north by Sand Creek Parkway, on the south by Independence Street and Guthrie Lane, on the east by Sellers Avenue and on the west by Brentwood Boulevard, according to the district.
That area includes Liberty High School, Brentwood Park, a handful of farming fields and several residential neighborhoods.
There is no need for residents to relocate during insect fogging, according to the district, as the pesticides used have been found to pose minimal risks to human health and the local environment.
The chemical to be used Thursday is Pyrocide 7396, and it will be sprayed at a rate of three-quarters of an ounce per acre, according to the district. The active ingredient is pyrethrin, a substance derived from chrysanthemum flowers, according to the Environmental Protection Agency.
Three human cases of West Nile virus were reported in Contra Costa County in 2011, but the virus hasn't been
Mild symptoms include fever, headache, fatigue, occasional skin rashes and fatigue, but a serious infection can bring on symptoms that include disorientation, muscle tremors, partial paralysis and convulsions.
District officials urged residents to be sure to use mosquito repellent.
They are also asking the public to check their properties for standing water and to report any sources that attract the insects. Neglected swimming pools can produce more than 1 million mosquitoes, officials said, and outbreaks can be reported by calling 925-771-6195 or visiting www.contracostamosquito.com.
Staff writer Rick Hurd contributed to this report. Contact Sean Maher at 925-943-8013. Follow him on Twitter at twitter.com/OneSeanMaher.