Health officials hailed shots for kids aged 5 to 11 as a major breakthrough after more than 18 months of illness, hospitalizations, deaths and disrupted education.

Kid-sized doses of the Pfizer-BioNTech vaccine cleared two final hurdles Tuesday _ a recommendation from CDC advisers, followed by a green light from Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention.

At a Decatur, Georgia, pediatrician’s office Wednesday, 10-year-old Mackenzie Olson took off her black leather jacket and rolled up her sleeve as her mother looked on.

“I see my friends but not the way I want to. I want to hug them, play games with them that we don’t normally get to,” and have a pillow fight with her best friend, Mackenzie said after getting her shot at the Children’s Medical Group site.

With the federal government promising enough vaccine to protect the nation’s 28 million kids in this age group, pediatricians’ offices and hospitals began inoculating children, with schools, pharmacies and other locations planning to follow suit in the days ahead.

The atmosphere surrounding the launch of shots for elementary-age students was festive in many locations. California vaccine sites welcomed children with kid-friendly motifs like inflatable animals and handed out coloring books and prizes. Vehicles lined up before dawn at an Atlanta site where a 10-year-old girl bounced around her family’s car in excitement.

Many pediatricians’ offices were expecting strong interest in the shots at least initially, but health officials are worried about demand tapering off. Almost two-thirds of parents recently polled by the Kaiser Family Foundation said they would wait or not seek out vaccines for their kids.

Brian Giglio, 40, of Alexandria, Virginia, brought his 8-year-old son, Carter, in for vaccination at Children’s National Hospital in Washington, D.C., where kids with underlying conditions got first dibs. Carter has Type 1 diabetes that puts him at risk for complications if he were to become infected.

Giglio said the vaccine was “like a hallway pass for us to begin living life again.” And Carter said he can’t wait to leave masks behind once he’s fully vaccinated, so he can smell the things he used to be able to smell without it.

“I’m ready to trash it,” he said, though the CDC still recommends masks in schools and indoor public spaces where virus activity is high, even for the fully vaccinated.

Cate Zeigler-Amon, 10, was first in line Wednesday for a drive-through vaccination at Viral Solutions in Atlanta. The girl enthusiastically bounced around the car before the shot, which she broadcast live on her computer during morning announcements at her elementary school.