A dead bird found in Pleasant Hill has tested positive for West Nile virus, Contra Costa Mosquito and Vector Control District officials announced Thursday.
A resident spotted the dead bird near the corner of Chilpancingo Parkway and Camelback Road, district officials said.
Birds carry the virus and pass it on to mosquitoes when the mosquito bites them. Mosquitoes can then pass on the virus to humans through a mosquito bite, according to district officials.
"We are thankful that a resident reported the bird, which gives us the opportunity to understand where virus activity may be taking place in the county," district spokeswoman Deborah Bass said in a statement.
"Our goal is always to treat mosquitoes in their larvae form, in the water, before they have a chance to become flying adults, get the disease from birds, and then infect people. Reports such as these help us toward that goal," Bass said.