CONCORD, CALIFORNIA – The Contra Costa Mosquito and Vector Control District (District) confirms a California scrub jay from San Ramon is the first bird to test positive for West Nile virus (WNV) in Contra Costa County this year.
The bird was reported to the California WNV Call Center and subsequent testing confirmed the bird was infected with WNV. Infected birds are often the first sign of WNV in Contra Costa County. Alameda and Santa Clara Counties have also reported infected birds so far this year.
“We typically start seeing West Nile-positive birds and mosquitoes in Contra Costa County around this time of year”, said Steve Schutz, Ph.D., Scientific Program Manager. “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.”
To reduce the risk of mosquitoes, the District recommends Contra Costa County residents dump out any amount of standing water at least once per week. And if, after dumping out all of the water on the property, the resident still experiences mosquito issues, Contra Costa County residents can contact the District to request mosquito service.
To reduce the risk of mosquito bites, 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. and report dead birds because dead birds are often the first sign of WNV in a particular location.
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
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