22 Jul West Nile Virus Detected in County

A Culex tarsalis mosquito, resting on human skin, is currently the main vector of West Nile virus in the western United States. (James Gathany / Centers for Disease Control via Bay City News)

By Audrey Tomlin
Bay City News

The Contra Costa Mosquito and Vector Control District has detected West Nile Virus in the area, the district confirmed on Monday.

A California scrub jay in San Ramon tested positive for the virus, the district said. The scrub jay represents the first bird to test positive for the virus in Contra Costa this year, but both Alameda and Santa Clara counties have also reported infected birds this year, according to a release from the district. Infected birds are often the first sign of the presence of West Nile virus in a particular location, it said.

“We typically start seeing West Nile-positive birds and mosquitoes in Contra Costa County around this time of year,” said Steve Schutz, scientific program manager at the district. “Our neighboring counties have been reporting positive samples for several weeks now. As the weather warms up, the risk of human cases will continue to increase.”

Mosquitoes can spread the virus to humans after feeding on birds that carry the virus. To reduce the risk of mosquito bites and to cut down on the overall mosquito population, Contra Costa residents should dump out any standing water at least once a week, where the insects lay their eggs.

To reduce the risk of mosquito bites, the district recommends using an EPA-registered insect repellent.

Anyone experiencing mosquito issues or who has questions can contact the District at (925) 685-9301 or online at www.contracostamosquito.com.

The district also recommends reporting dead birds. Residents can do so at (877) 968-2473 or online.

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