A dead Western scrub jay found last week in Antioch also tested positive for West Nile virus. Based on the number of dead bird reports, the area east of Somersville Road, west of Deer Valley Road, south of Highway 4 and north of Empire Mine Road in Antioch is at highest risk for West Nile in Contra Costa County, said Deborah Bass, public affairs manager with the Contra Costa Mosquito and Vector Control District.
The current heat wave is expected to increase the risk of West Nile because higher temperatures speed the rate at which the virus replicates in mosquitoes' salivary glands, according to Vector Control.
Property owners are encouraged to routinely check yards and dispose of mosquito water sources, Bass said. They should also maintain water features around their homes.