The county's Division of Vector Control was scheduled to treat the area Thursday, weather permitting.
In Suffolk, no animals or humans have tested positive for West Nile virus yet this year, said officials at the county's Department of Health.
Dead birds can indicate the virus, and health officials ask residents who find one to call the West Nile virus hotline at 631-787-2200.
To report mosquito problems or stagnant pools, call the Department of Public Works' Vector Control Division at 631-852-4270. For medical questions related to West Nile virus, call 631-853-3055.
For further information on West Nile virus, or mosquito spraying schedules, see suffolkcountyny.gov/health.
The county planned to spray Thursday night for mosquitoes in Fire Island Pines and Water Island from 6:30 to 10:30 p.m.; in Babylon, North Babylon, West Babylon and North Lindenhurst from 8:30 to 11:30 p.m.; and Mastic Beach, Old Mastic and south Shirley from 7:30 to 11:30 p.m.
Children and pregnant women should remain inside or avoid the area during spraying and for about 30 minutes after. Close windows and doors before spraying begins, and close the vents of or turn off window air-conditioning units.