The Sacramento-Yolo Mosquito & Vector Control District says a total of two mosquitoes and seven birds have been found in Wilton, Elk Grove and Citrus Heights.
Ground-fogging has been conducted in Wilton and at C-Bar-C Park in Citrus Heights.
The district says the cool weather has helped keep the number of infections at a relatively low level.
Combined, 25 birds and mosquitoes have tested positive for West Nile this year.
