CONCORD, CALIFORNIA - The Contra Costa Mosquito & Vector Control District (District) reports the first dead bird of the year, and more mosquitoes have tested positive for West Nile virus (WNV) in Contra Costa County.

The dead bird, a California scrub-jay, was picked up in Brentwood. The mosquitoes were collected from a trap in Discovery Bay. Both cities are in eastern Contra Costa County. There are now one dead bird and five groups of mosquitoes that have tested positive for WNV so far this year in Contra Costa County.

Certain birds carry WNV. Once a mosquito bites an infected bird, the mosquito can become infected. Mosquitoes can spread the virus when they bite another bird or person. To reduce the risk of WNV, the District recommends Contra Costa County residents report dead birds because dead birds are often the first sign of WNV in a particular location.

As we enter the Labor Day weekend, continued WNV activity in Contra Costa County serves as an important reminder to residents to also take precautions to reduce the risk of WNV by avoiding mosquito bites.

"Because infected mosquitoes can spread West Nile virus to people through a single mosquito bite, it's important that Contra Costa County residents take precautions to avoid mosquito bites, particularly over this holiday weekend when many people will be enjoying holiday events outdoors. And historically, we see the highest risk of human cases in late August and September. To reduce the risk, use an effective insect repellent when outdoors, particularly just before and after sunrise and sunset. Wear long-sleeve shirts and long pants to avoid areas of exposed skin that can be bitten. And avoid being outdoors where mosquitoes are present," said Steve Schutz, Ph.D., Scientific Program Manager.

According to the Centers for Disease Control and Prevention (CDC) when used as directed, Environmental Protection Agency (EPA)-registered insect repellents are proven safe and effective. The District recommends using EPA-registered insect repellents with one of the following active ingredients:

Always follow the instructions on the label when using insect repellent.

Contra Costa County residents can report dead birds by phone at (877) WNV-BIRD (968-2473) or online. County residents can also request mosquito service for residential property by calling (925) 685-9301 or online.

Contra Costa Mosquito & Vector Control District, an independent special district and public health agency, is located at 155 Mason Circle in Concord. Contact the District to report mosquito problems online or at (925) 685-9301.