While children still make up a small percentage of overall Covid-19 hospitalizations, rates of pediatric Covid-19 hospitalizations are rising to record numbers—and experts say the rise likely stems from low pediatric vaccination rates.

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Pediatric Covid-19 hospitalizations rise

During the week of Dec. 22 to Dec. 28, 2021, an average of 378 children ages 17 and younger were admitted to the hospital each day with Covid-19, according to CDC, which represented a 66% increase from the previous week.

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The number also represents a new record for pediatric Covid-19 hospitalizations during the pandemic, according to CDC. The previous high was an average of 342 hospitalizations per day in September 2021, the agency said.

However, children still represent a small portion of Covid-19 hospitalizations overall. During the same week in December reported by CDC, an average of 10,200 people of all ages were hospitalized with Covid-19.

In total, more than 76,000 children were hospitalized with Covid-19 between Aug. 1 and Dec. 28, 2021, The Hill reports, and the American Pediatric Association estimated there was a 5% increase in the number of children who tested positive for the coronavirus between Dec. 9 and Dec. 23.

Vast majority of hospitalized children are unvaccinated

According to a report released Thursday by CDC, just 0.4% of children and adolescents admitted to six hospitals in July and August with Covid-19 were fully vaccinated, showing that "unvaccinated children hospitalized for Covid-19 could experience severe disease," according to the study authors.

Similarly, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, noted on Thursday that "[v]irtually all, not 100% but close to that, [of] the children who are seriously ill in our hospitals from Covid-19 are children whose parents decided they did not want to vaccinate them."

"That is avoidable," Fauci added, saying that some children who are hospitalized with Covid-19 "need not be in that situation if they were vaccinated."

"It's just so heartbreaking," said Paul Offit, an infectious disease expert at Children's Hospital of Philadelphia. "It was hard enough last year, but now you know that you have a way to prevent all this."

CDC study shows vaccine adverse effects are rare among children

A study released by CDC found that adverse side effects to Covid-19 vaccines were extremely rare among children ages 5 to 11.

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For the study, researchers looked at data on 42,504 children ages 5 to 11 between Nov. 3 and Dec. 19, 2021, collected through the Vaccine Adverse Event Reporting System, which is a "voluntary smartphone-based safety surveillance system" co-managed by CDC and FDA.

During the time period, a total of 4,249 adverse events were reported post-vaccination, and 97.6% of them were considered non-serious. About 58% of children reported localized reactions to the shot, and about 41% reported systemic reactions like fatigue or headaches, the study found.

Two deaths were reported post-vaccination during the time period. However, the study said both of those children had "complicated medical histories" and "fragile health" before they were immunized.

FDA expands booster eligibility

Meanwhile, FDA on Monday expanded eligibility for booster shots of the Pfizer-BioNTech Covid-19 vaccine to children ages 12 to 15 years old and shortened the time between a person's second dose of a Covid-19 vaccine and booster shot to at least five months rather than six.

FDA also said children ages 5 to 11 who have compromised immune systems can receive a third dose of the vaccine as part of the primary series of shots.

Former FDA Commissioner Scott Gottlieb on Sunday said that parents and doctors should determine whether children need booster shots of Covid-19 vaccines and that schools should not mandate them.

Gottlieb noted that children, especially those between 12 and 16 years old, have better vaccine durability than adults and overall have a lower risk from infection.

"I certainly don't think schools should be mandating boosters," Gottlieb said. "I think this should be left up to the discretion of parents and their physicians. You know, it's going to depend on the individual circumstance." (Beals, The Hill, 12/30/21; Bellisle/Tang, Associated Press, 12/30/21; Dress, The Hill, 12/31/21; Choi, The Hill, 12/30/21; Vakil, The Hill, 1/2; Kimball, CNBC, 1/3)