CONCORD, CALIFORNIA – The Contra Costa Mosquito and Vector Control District (District) confirms mosquitoes collected from a trap in Holland Tract are the second group of mosquitoes to test positive for West Nile virus (WNV) in Contra Costa County this year. These mosquitoes were collected from the same location as the first group of mosquitoes to test positive for WNV this year.
“Although fall is officially here, overnight temperatures are still warm enough for mosquitoes and West Nile virus transmission, especially with the recent (but fortunately brief) heat waves. The risk of disease will continue until average overnight temperatures drop below 55°, so residents should continue to protect themselves from mosquito bites and reduce the risk of mosquitoes on their own properties,” said Steve Schutz, Ph.D., Scientific Programs Manager.
To reduce the risk of mosquitoes, the District encourages Contra Costa County residents to dump out any amount of standing water at least once every week. And 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.
To reduce the risk of mosquito bites, the District encourages residents to 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.
