Is the Pfizer vaccine that is being evaluated by federal health officials for younger children the exact same vaccine that teenagers and adults received?
According to Chicago Department of Public Health Commissioner Dr. Allison Arwady, the answer is no.
Full-strength Pfizer shots are recommended for anyone 12 or older, but many pediatricians and parents are anxiously awaiting protection for younger children to stem infections from the extra-contagious delta variant and help keep kids in school.
On Tuesday, a panel of advisers for the U.S. Food and Drug Administration gave Pfizer's child-size COVID vaccine its endorsement.
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While the vaccine for younger children has "the exact same ingredients" and will follow the same timeframe between doses, "it is only going to be a third the dose."
"This is because younger children have a smaller body mass and in studies, they had the same level of antibodies and protection," Arwady said. "But the lower dose makes it less likely that the 5-to-11-year-olds will have side effects."
Arwady noted that the change in dosage will also require smaller needles and different vaccine vials.
"So we won't have people pulling adult and children doses out of the same vial, there is a separate process for child vaccines," she said.
If the FDA authorizes the shots, the CDC will make additional recommendations on who should receive them the first week of November.
Children could begin vaccinations early next month -- with the first youngsters in line fully protected by Christmas.
Illinois Gov. J.B. Pritzker said final approval for vaccines in this age group could come in the middle of next week, clearing the way for the state to begin vaccinations.
"In just a few days time, millions of parents all across the United States should be able to breathe a sigh of relief that they've been holding in for over 18 months now," Pritzker said.
Federal health regulators said late Friday that child-size doses of Pfizer’s COVID-19 vaccine appear highly effective at preventing symptomatic infections in elementary school children and caused no unexpected safety issues.
In their analysis, FDA scientists concluded that in almost every scenario the vaccine's benefit for preventing hospitalizations and death from COVID-19 would outweigh any serious potential side effects in children. But agency reviewers stopped short of calling for Pfizer's shot to be authorized.
The FDA review found no new or unexpected side effects. Those that did occur mostly consisted of sore arms, fever or achiness.
However, FDA scientists noted that the study wasn't large enough to detect extremely rare side effects, including myocarditis, a type of heart inflammation that occasionally occurs after the second dose.
While children run a lower risk of severe illness or death than older people, COVID-19 has killed more than 630 Americans 18 and under, according to the CDC. Nearly 6.2 million children have been infected with the coronavirus, more than 1.1 million in the last six weeks as the delta variant surged, the American Academy of Pediatrics says.