CONCORD, Calif. (KRON) – The first dead bird in 2021, in addition to more mosquitoes, have tested positive for West Nile virus, according to the Contra Costa Mosquito and Vector Control District.

A California scrub-jay was found in Brentwood and the mosquitoes were nearby in Discovery Bay.

This year in Contra Costa County, five groups of mosquitoes and now one dead bird have tested positive for the virus.

Officials say some birds carry the virus and if a mosquito bites the bird and becomes infected, the mosquito can spread it to another bird or person.

“Because infected mosquitoes can spread West Nile virus to people through a single mosquito bite, it’s important that Contra Costa County residents take precautions to avoid mosquito bites, particularly over this holiday weekend when many people will be enjoying holiday events outdoors. And historically, we see the highest risk of human cases in late August and September. To reduce the risk, use an effective insect repellent when outdoors, particularly just before and after sunrise and sunset. Wear long-sleeve shirts and long pants to avoid areas of exposed skin that can be bitten. And avoid being outdoors where mosquitoes are present,” said Steve Schutz, Ph.D., Scientific Program Manager.

Residents are advised to take extra precautions heading into Labor Day weekend.

If you see a dead bird, it is advised to report it to the district as this is ‘often the first sign of West Nile Virus in a particular location.’

To report dead birds, call (877) 968-2473 or online.

In the last 16 years, 73 people in the county have been diagnosed with West Nile virus and two people have died since 2006.