ALAMO -- A dead American crow is the first bird to test positive for the West Nile virus in the new season, according to officials from the county's Mosquito and Vector Control District.
The crow was recently found near the intersection of Danville Boulevard and Camille Place and was the first bird to be tested for the new mosquito season.
"This bird is one of the earliest signs of the West Nile virus we've had in a season in the county to date," said Steve Schutz, the district's scientific program manager, in a news release Friday.
Schutz added it was "no big surprise" the virus has already been detected in Contra Costa County. He said signs of an early season, such as the unusually warm winter in the county, has allowed mosquitoes to thrive. As a result, district mosquito inspectors are already treating mosquitoes sources a month earlier than usual, according to the district.
Since 2005, when the virus first surfaced in Contra Costa County, there have only been two earlier starts to the West Nile virus season, according to district spokeswoman Deborah Bass.
"Unfortunately, the earlier West Nile virus is detected, the earlier we may see human cases," Schutz said.
The two species of mosquitoes in Contra Costa County capable of transmitting the virus prefer to feed on birds; however, people can become infected when a mosquito bites an infected bird and then a person, according to the district. Many people who become infected with the virus show no symptoms, while others exhibit flu-like symptoms including fever, head and body aches, diarrhea or a rash.
In 2012, the last year for which there are records, roughly 212 Contra Costa County residents were infected with the disease, according to Bass.
Residents are also advised to avoid having any standing water near or around their home, to avoid being outdoors when mosquitoes are present, usually at dawn or dusk, and to wear mosquito repellents while outdoors.
The report dead birds, which can then be tested for the virus, call the state hotline at 877-968-2473 or visit www.westnile.ca.gov.
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