A dead bird found in Alamo has tested positive for West Nile virus, the first virus-positive bird to be documented in Contra Costa County this year, the Contra Costa Mosquito and Vector Control District announced Thursday.
The bird, a western scrub jay, was found June 28. Test results came back Wednesday confirming that it had West Nile virus.
Earlier this season, 11 mosquito samples also tested positive for the virus, but the bird is the first evidence this year of the virus' transmission.
In 2008, five people from Antioch, Brentwood, Oakley and Martinez tested positive for the virus, according to Contra Costa Health Services.
The mosquito district is urging people to wear insect repellent, make sure that their door and window screens are in good condition and drain all sources of standing water on their property. People should also vaccinate horses to protect them from the virus.