Coronavirus vaccinations for kids under 12 cleared the next phase of the authorization process on Tuesday.
A panel of experts for the Centers for Disease Control and Prevention unanimously endorsed the kid-size shots, putting the U.S. on the brink of a major expansion of vaccinations.
If the CDC’s director, Dr. Rochelle Walensky, signs off as expected, it will mark the first opportunity for Americans under 12 to get the powerful protection of any COVID-19 vaccine.
Once the CDC recommends, children could begin vaccinations as soon as Thursday -- with the first youngsters in line fully protected by Christmas.
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Last week, the Food and Drug Administration authorized Pfizer's COVID vaccine for children ages 5-11.
Full-strength Pfizer shots already are recommended for anyone 12 or older, but pediatricians and many parents are anxiously awaiting protection for younger children to stem infections from the extra-contagious delta variant and help keep kids in school.
While the vaccine for children ages 5-11 has "the exact same ingredients" and will follow the same timeframe between doses, "it is only going to be a third the dose," according to Chicago Department of Public Health Commissioner Dr. Allison Arwady.
"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.
Illinois Gov. J.B. Pritzker said the state has been preparing for the youth shots.
More than 2,200 locations and providers in the state - including family medicine practices, urgent care centers and public health clinics - have enrolled to provide doses to children, Pritzker said in a release.
Initially, the state will receive approximately 306,000 doses for kids 5 to 11, with an additional 73,000 doses for the city of Chicago and more than 100,000 headed to federal government pharmacy partners.
"As a parent, you should call your pediatrician now to make sure they’ve enrolled and have ordered doses," he said. "And I will do everything in my power to continue to follow the science and keep our kids safe.”
Federal health regulators said 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.
Most of the study data was collected in the U.S. during August and September, when the delta variant had become the dominant COVID-19 strain.
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.
Doctors at Advocate Children's Hospital said last week that while cases in children tend to be less severe than those seen in adults, "more children are being hospitalized with severe COVID-19 infection than was seen earlier in the pandemic."
The group also warned that multiple cases of a life-threatening COVID-19-related condition called the pediatric multisystem inflammatory syndrome have been reported in the Chicago area and experts still don't know the long-term effects of COVID-19 on kids.
"As the state's top health officials, and as a board certified pediatrician and mom, I am urging every single parent and guardian to do this for their child," Illinois Department of Public Health Director Dr. Ngozi Ezike said last week. "Make a plan to get them vaccinated for COVID-19."
Both Moderna and J&J's vaccines can only be used on people 18 and older, though Moderna also is studying its shots in elementary school-aged children.