CONCORD, CALIFORNIA – The Contra Costa Mosquito and Vector Control District (District) confirms a young American crow from El Cerrito is the first bird to test positive for West Nile virus (WNV) in Contra Costa County this year.
“West Nile virus has been detected in local bird and mosquito populations almost every summer, and the risk of disease transmission will persist until the weather cools off in the fall. So far this summer, one group of mosquitoes from Martinez and one dead bird from El Cerrito have tested positive. The District recommends that all Contra Costa County residents take steps to protect themselves from West Nile virus by avoiding mosquito bites,” said Steve Schutz, Ph.D., Scientific Programs Manager.
Mosquitoes typically become infected with WNV after biting an infected bird. Dead bird reports to the California West Nile Virus Call Center provide important information to the District, as dead birds are often the first sign of WNV in a particular location.
With this weekend’s 4th of July festivities happening across Contra Costa County, it is more important than ever to take precautions to reduce the risk of mosquito bites. As the parades and fireworks will happen at the time of day when the mosquitoes that can transmit West Nile virus are most active, the District recommends residents use EPA-registered insect repellents with one of the following active ingredients:
- DEET
- Picaridin
- The repellent version of Oil of Lemon Eucalyptus
- IR3535
Always follow the instructions on the label when using insect repellent.
To reduce the risk of mosquitoes, the District recommends Contra Costa County residents walk around their front and back yards at least once each week and dump out any amount of standing water to remove locations where mosquitoes can be produced.
If, after dumping out all of the water on the property, the resident still experiences mosquito issues, Contra Costa County residents should contact the District to request mosquito service. Contra Costa County residents pay for District services through property taxes, so there is no additional charge for county residents to request a District service.
Contra Costa County residents can report dead birds by phone at (877) WNV-BIRD (968-2473) or online. County residents can also request mosquito
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