By CBS3 Staff

PHILADELPHIA (CBS) — Philadelphia will begin vaccinating children ages 12-15 on Thursday after the U.S. Center for Disease Control and Prevention gave its recommendation. The CDC followed the U.S. Food and Drug Administration in recommending the Pfizer vaccine for children 12-15.

It was already approved for those over the age of 16.

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Officials said Wednesday night that at city-run vaccination sites, children ages 12-15 must be accompanied by a parent or guardian with proof of date of birth. That includes access to school or health care portals via cellphone, copy of school or sports health forms, insurance cards, passports, birth certificates or a photo of their birth certificate, or any other document that has the child’s name and date of birth on it.

The city said anywhere that offers the Pfizer vaccine can begin vaccinating children 12-15.

Most city-run clinics have the vaccine, according to the city, including the Center City Vaccination Center.

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The city warns that not all sites in the city have the Pfizer vaccine, so anyone looking to get vaccinated should double-check by calling ahead to confirm the clinic offers it.

Philadelphia residents can find out which city-run clinics offer the Pfizer vaccine and make an appointment by clicking here. For that information at private-run sites, you can click here.

Even before the CDC vote on Wednesday, teenagers were receiving the Pfizer vaccine on Tuesday at the King of Prussia Mall.

“We have been eagerly anticipating the extension to every person,” said Amy Laursen, a mom.

“I’ll be able to hang out with my friends again,” Helena Laursen said, “because I’ve been hanging out with them only like outside and like really far apart, so it’ll be nice to get to see them closer.”

Research on 2,000 teens showed the vaccine is safe and effective. They received the same dose as adults but developed even higher levels of virus-fighting antibodies.

Updated numbers show 22 million children between the ages 5 and 17 have been infected with COVID-19, accounting for 19% of all infections.

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Expanded authorization of the Pfizer vaccine means 85% of the U.S. population would be eligible to receive a COVID-19 vaccine.