Dr. Thomas Farley, New York City health commissioner, said the infected mosquitoes were collected from the neighborhoods of New Dorp Beach and Bull's Head on Staten Island and additional traps were installed. No human cases have been detected this season.
"Simple precautions can help protect you and your family," Farley said in a statement. "Wear mosquito repellent when you're outdoors, and cover your arms and legs if you're outside at dawn or dusk. People age 50 and older should be especially cautious, as they are more likely to develop serious illness if they contract the virus."
Not everyone bitten by an infected West Nile mosquito will become ill, Farley said.
In rare cases, West Nile can cause neurological diseases such as encephalitis, a serious inflammation of the brain or spinal cord. It can also cause a milder flu-like illness with headache, fever and fatigue, weakness and sometimes rash.
"If you think you have symptoms of West Nile virus, see a doctor right away," Farley said.
To reduce mosquito exposure:
-- Use an approved insect repellent containing DEET, picaridin, oil of lemon eucalyptus, not for children age 3 and under, or products that contain the active ingredient IR3535.
-- Ensure all windows have screens without holes.
-- Eliminate any standing water from your property since it provides breeding sites for mosquitoes.
-- Make sure roof gutters are clean and drain properly.
-- Clean and chlorinate swimming pools, outdoor saunas and hot tubs.