Pfizer COVID Vaccine for Kids Over 90 Percent Effective, Similar Side Effects as With Teens

Pfizer's COVID-19 vaccine for kids ages five to 11 is over 90 percent effective at preventing symptomatic infections, according to study results released Friday. The pharmaceutical company's long-awaited vaccine for younger children also caused similar or few temporary side effects during trials, like sore arms and fever, as with teens who received the shot, the Associated Press reported.

Rollout of the vaccine for young children could begin as soon as November, pending approval from regulators like the U.S. Food and Drug Administration and the Centers for Disease Control and Prevention.

Pfizer's study used 2,268 kids in the vaccine's intended age group. Each child either received two doses of a low-dose vaccine, one-third of the dose administered to teens and adults, or two placebo doses three weeks apart.

On top of determining that the vaccine was more than 90 percent effective, based on 16 COVID-19 cases in kids both with and without the vaccine, researchers also found that kids given the low-dose shots developed virus-fighting antibodies just as strong as teens and young adults who received the regular doses, the AP reported. An effective vaccine for younger Americans is especially important as hospitalization numbers for children without the vaccine soared to record levels in September.

For more reporting from the Associated Press, see below.

Pfizer Vaccine Vial
Pfizer’s COVID-19 vaccine for kids ages five to 11 is over 90 percent effective at preventing symptomatic infections, according to study results released Friday. A nurse reaches for a vial of Pfizer-BioNTech COVID-19 vaccine at... Robyn Beck/AFP via Getty Images

Details of Pfizer's study were posted online. The Food and Drug Administration (FDA) was expected to post its independent review of the company's safety and effectiveness data later in the day.

Advisers to the FDA will publicly debate the evidence next week. If the agency ultimately authorizes the shots, the Centers for Disease Control and Prevention will make the final decision on who should receive them.

Full-strength Pfizer shots already are authorized for anyone 12 or older, but pediatricians and many parents are anxiously awaiting protection for younger children to stem rising infections from the extra-contagious delta variant and help keep kids in school.

More than 25,000 pediatricians and primary care providers already have signed up to get the shots into little arms.

The Biden administration has purchased enough kid-size doses — in special orange-capped vials to distinguish them from adult vaccine — for the nation's roughly 28 million 5- to 11-year-olds. If the vaccine is cleared, millions of doses will be promptly shipped around the country, along with kid-size needles.

The CDC reported earlier this week that even as the Delta mutant surged between June and September, Pfizer vaccinations were 93 percent effective at preventing hospitalizations among 12- to 18-year-olds.

The study of vaccines in younger children isn't large enough to detect any extremely rare side effects, such as the heart inflammation that occasionally occurs after the second dose, mostly in young men.

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 mutant surged, the American Academy of Pediatrics says.

Moderna also is studying its COVID-19 shots in elementary school-age youngsters. Pfizer and Moderna are studying even younger children as well, down to 6-month-olds. Results are expected later in the year.

Kids Receive Pfizer Shot
The rollout of Pfizer's vaccine for children ages five to 11 could begin as soon as early November, pending the approval from regulators like the U.S. Food and Drug Administration and the Centers for Disease... Joseph Prezioso/AFP via Getty Images

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