When will children under 12 be able to get the COVID vaccine? Here's what we know

COVID cases are surging across the nation, and kids now account for more infections than they did in months past.   

Data from the CDC shows that an average of 280 people under 18 are contracting COVID every week, an increase of more than 20% since June. More than 120,000 cases were reported among children between Aug. 5 and 12, according to the American Academy of Pediatrics. That figure represented 18% of the total case count for that week.

Health experts say the Delta variant of the coronavirus is likely changing the calculus. While children showed strong natural immunity to earlier iterations, the Delta variant is 50% more contagious than past variants, and its meteoric ascendence to become the supreme strain in the U.S. coincides with the rising number of infections in children.

“Because Delta is so much more transmissible than the earlier variants of the coronavirus, what we see is that there’s much higher community prevalence,” said Dr. Alpana Waghmare, a pediatric infectious disease specialist at Seattle Children’s Hospital. “Whenever there’s higher community prevalence, there’s going to be more kids that get infected.”

With most of Washington’s public schools slated to start in the coming weeks, many parents are wondering why COVID vaccines haven’t been approved for children under 12.

Here’s what we know about the process for getting kids under 12 vaccinated. 

When will a vaccine be approved for children under 12?

Here’s the short answer: Tentatively, late this year or early next year. The exact date depends on the child’s age. Older kids will likely get vaccinated sooner, while toddlers and babies will probably have to wait.  

Now, for the long answer.

Pfizer is enrolling more than 4,600 children in its clinical trials. The kids are divided into three age groups: 5-11, 2-5 and those between 6 months and 2 years old.

Waghmare said she expects the vaccine to be approved for the three age groups in descending order, which is consistent with the company’s current timetable. That means, if approved, a vaccine for kids ages 5 to 11 would come first.

Pfizer spokesperson Keanna Ghazvini said the company expects to have data for that age group by the end of next month. She said Pfizer could ask the U.S. Food and Drug Administration (FDA) for an emergency use authorization shortly thereafter.

Data for children under 5 will likely be submitted to the FDA by the end of 2021, Ghazvini said.

Moderna is slightly behind Pfizer in its timetable. It expects to submit data to the FDA for ages 6-11 later this year. Data for those under 6 will likely be submitted early next year.

The company recently expanded the size of its trial to include roughly 12,000 children amid worries that shots may trigger rare heart side effects. Pfizer has not said whether it will update its timeline or the size of its trial, despite fretting from federal regulators.

Johnson & Johnson has not yet begun clinical trials for children under 12.

Approval for emergency use authorizations can take several weeks. That means — assuming Pfizer and Moderna stick to their respective timelines — we could see vaccines being administered to children late this year through early next year.

Why do kids under 12 need a separate vaccine?

Children tend to have a naturally robust immune response, Waghmare said. That means their bodies typically mount a stronger and quicker defense against threats than adult bodies do.

Because of this, children may need a lower dose of the vaccine. Giving them too much could result in adverse effects, Waghmare said.

This creates a balancing act for scientists: They need to produce a vaccine that’s strong enough to protect kids against COVID, but not one that’s so strong that it does more harm than good.

“What we want is a vaccine that produces a good immune response and has good protection, but doesn’t have so many side effects,” said Waghmare. “That’s problematic for the kids and could make people unwilling to give a vaccine to their children.”

Why is age 12 the cutoff?

Though the threshold is a bit arbitrary, Waghmare said age 12 has been traditionally used as the cutoff in past studies.

“There’s not a magic change that happens at 12,” she said. “It’s a number that’s been historically used in vaccine studies and trials, so I think there was some precedent to pick it.”

Why has it taken this long?

The main reason is that COVID hit older people the hardest.

“In the setting of a pandemic, where we know disease severity overall is much worse for adults than kids, I think there was a priority to get the adult study completed,” Waghmare said.

Also, vaccine studies traditionally focus on adults first before moving to other age groups.

“That’s how all these studies work,” Waghmare said. “They always start with adults before they go to kids, so that’s not surprising.”