NEW YORK (CBSNewYork) -- The New York City Department of Health has announced new measures to fight this year's outbreak of the flu.
Starting Dec. 31, kids ages 6 months to 59 months will be required to get the flu shot.
The Health Department says it's trying to address the increased influenza risk facing children under 5 in group settings such as preschools and child care centers.
In announcing its new mandate, the Health Department said more than 100 children died from the virus nationwide during last flu season, according to the Centers for Disease Control. So far this season, seven pediatric deaths have been reported.
Earlier this month, the state Department of Health said the virus is now "prevalent" in New York.
On Long Island, Nassau County Health Commissioner Dr. Lawrence Eisenstein said the county is dealing with a flu cluster.
At Lee Road Elementary School in the Levittown School District , 115 students were absent Tuesday. Of those, 32 have the flu, according to their parents.
"We have a few confirmed cases, and our disease investigators are now out evaluating why all the children are out," Eisenstein said. "Certainly, not all the children are absent because of the flu."
L.I. School District Dealing With Possible Flu Outbreak
Della Ng said her daughter was home sick with the virus and she took her son out of school with symptoms.
"They get headache, stuffy nose and a lot of fever," she said.
Ng said both of her kids got the flu shot.
"We don't really know where it's coming from," she said. "Everyone from around here has it."
Nassau Health Commissioner Stresses Importance Of Flu Shots
The U.S. Centers for Disease Control and Prevention said earlier this month that this year's vaccine prevents less than half of flu cases because the current strain of the virus mutated.
Still, experts say in addition to plenty of hand washing, the vaccine is important.
"It is the single best preventive measure that we have to help people avoid the flu," said Eisenstein.
Eisenstein told WCBS 880's Sophia Hall that more than half the kids confirmed to have the flu in Levittown did not receive flu shots.
The Levittown School District is asking parents to bring kids with a fever to the doctor. It also says all touched surfaces have been thoroughly cleaned.
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