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WASHINGTON - Following the full approval by U.S. regulators of Pfizer’s COVID-19 vaccine for Americans age 16 and older, many parents are still wondering when a vaccine will be made available for younger children as schools across the country resume classes amid a delta variant surge.
A need for a vaccine for younger children has taken on a new urgency due to the new wave of COVID-19 infections. As of Aug. 16, 1,900 children in the United States were hospitalized with COVID-19, according to the U.S. Department of Health and Human Services — setting a new pandemic record for kids.
While many experts say vaccines for children are desperately needed, some say it may be a while before parents with younger kids can get their shots.
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Speaking on NPR’s "Morning Edition" On Aug. 24, National Institutes of Health Director Dr. Francis Collins said it’s "unlikely" that there will be federal approval of COVID-19 vaccines for young children before the end of this year.
"I've got to be honest, I don't see the approval for kids — 5 to 11 — coming much before the end of 2021," Collins said.
Until a vaccine for children becomes widely available, Collins pressed the importance of face masks to curb the spread of the virus.
"If you want to avoid having that outbreak that's going to send all the kids home again, you should be doing everything to avoid that. And that means wearing masks," Collins told NPR. "And by the way, if somebody tries to tell you we don't really have scientific evidence to say that masks reduce infection in schools, that's just not true. There are dozens of publications, both from the U.S. and other countries, to show that's the case. So, boy, I wish we could get over that fight."
RELATED: Younger children more likely to spread COVID-19 in homes than older children, study says
Collins’ comments came after a new study published in "The Journal of American Medicine Association" earlier this month suggested that younger children are more likely to spread COVID-19 within households compared to older children.
According to the study, the highest odds of transmission were in children between 0 and 3 years old compared to children between 14 and 17 years old. Children between 4 and 13 years old also had increased odds of transmitting the virus but not as high compared to the younger demographic.
"As the number of pediatric cases increases worldwide, the role of children in household transmission will continue to grow," the researchers wrote. "We found that younger children may be more likely to transmit SARS-CoV-2 infection compared with older children, and the highest odds of transmission were observed for children aged 0 to 3 years."
A few weeks into the new school year, growing numbers of U.S. districts have halted in-person learning or switched to hybrid models because of rapidly mounting coronavirus infections.
More than 80 school districts or charter networks have closed or delayed in-person classes for at least one entire school in more than a dozen states. Others have sent home whole grade levels or asked half their students to stay home on hybrid schedules.
The setbacks in mostly small, rural districts that were among the first to return dampen hopes for a sustained, widespread return to classrooms after two years of schooling disrupted by the pandemic.
In Georgia, where in-person classes are on hold in more than 20 districts that started the school year without mask requirements, some superintendents say the virus appeared to be spreading in schools before they sent students home.
"We just couldn’t manage it with that much staff out, having to cover classes and the spread so rapid," said Eddie Morris, superintendent of the 1,050-student Johnson County district in Georgia. With 40% of students in quarantine or isolation, the district shifted last week to online instruction until Sept. 13.
More than 1 of every 100 school-aged children has tested positive for COVID-19 in the past two weeks in Georgia, according to state health data published Friday. Children age 5 to 17 are currently more likely to test positive for COVID-19 than adults.
On Sunday, Dr. Anthony Fauci said in an interview on CNN’s "State of the Union" that he supports COVID-19 vaccine mandates for eligible children attending in-person classes.
Fauci said he is anticipating federal regulators to soon establish "the safety and the strong benefit-risk ratio for the children," when it comes to vaccines.
"When that gets established, which I believe it certainly will... I believe that mandating vaccines for children to appear in school is a good idea," Fauci said.
The FDA, like regulators in Europe and much of the rest of the world, initially allowed emergency use of Pfizer’s vaccine based on a study that tracked 44,000 people 16 and older for at least two months — the time period when serious side effects typically arise.
That’s shorter than the six months of safety data normally required for full approval. So Pfizer kept that study going, and the FDA also examined real-world safety evidence.
Pfizer’s shot will continue to be dispensed to 12- to 15-year-olds under an emergency use authorization until the company files its application for full approval.
Normally, doctors can prescribe FDA-approved products for other reasons than their original use. But FDA’s acting Commissioner Dr. Janet Woodcock strongly warned that the Pfizer vaccine should not be used "off-label" for children under 12 — a warning echoed by the American Academy of Pediatrics.
Both Pfizer and Moderna have vaccine studies underway in youngsters, and they are using lower doses than those available for people 12 and older.
Pfizer’s CEO said he expects study results from 5- to 11-year-olds by the end of September, but data for those younger than 5 will take a couple of months.
This story was reported from Los Angeles. Chris Williams and The Associated Press contributed.