Sacramento-Yolo Mosquito and Vector Control continues to see evidence of "widespread West Nile virus activity" throughout Sacramento County.
Just released laboratory tests confirm 19 mosquito samples and 18 dead birds tested positive for the virus.
Vector Control officials say they expect hot summer temperatures to amplify the virus, and they are keeping a close eye on the Citrus Heights area.
Yolo County has also seen activity and some of the dead birds that have recently tested positive were from Davis.
Aerial spraying to combat mosquitoes carrying the West Nile virus have reportedly cut down the number of mosquitoes and infection rates have decreased significantly in the areas treated compared to untreated areas.