The West Nile virus has been detected in mosquitoes from Eltingville, a community in southern Staten Island, according to city health officials.
It's the first detection of the virus so far this season, and that no human cases have been reported at this time, they said.
The virus usually causes mild, flu-like symptoms, but officials said it can also cause more serious conditions, like neurological diseases including encephalitis, particularly among the elderly.
Using insect repellent that contains DEET and keeping away from standing water usually draws breeding mosquitoes is recommended.
The health department said it's stepped-up monitoring of mosquitoes in Eltingville.