Why vaccinating kids is key to ending pandemic

Even if every adult in Illinois elected to receive a COVID-19 vaccination, that's still not enough people to achieve herd immunity.

Most health experts believe at least 80% of the population needs a vaccine to potentially reach that immunity goal, though many suspect it's even higher.

And since not every adult in Illinois can be vaccinated — or is willing to be immunized — the estimated 22% of Illinois' population under age 18 is key to the state's efforts to help end the pandemic.

However, the vaccines haven't been approved for most in that age group, and it'll be months before that happens.

“We're hearing everything from midsummer to early fall for vaccine being approved or authorized for use on children,” said Dr. Emily Landon, head of the University of Chicago's infectious disease prevention and control program. “But I don't know how optimistic those times are.”

The Pfizer/BioNTech two-dose vaccine is available to anyone 16 and older and clinical trials on children ages 12 to 15 are wrapping up, while trials of that vaccine on children ages 6 to 12 have recently started, she said. Meanwhile, the Moderna two-dose vaccine is being tested on children ages 12 to 18, with trials for younger children expected soon. There currently are no clinical trials planned for children with the single-dose Johnson & Johnson vaccine.

Children “are absolutely essential in getting as much immunity into a community as possible,” Landon said. “And you're going to need a lot of kids.”

The parents of more than 9,500 children registered their kids for vaccine trials through Chicago's Lurie Children's Hospital, according to Dr. Taylor Heald-Sargent, assistant professor of pediatric infectious diseases at Lurie and Northwestern Medical Center.

Not all of those children will be part of the trials, she said.

“I don't think it's been particularly hard finding volunteers,” she explained. “Parents are really wanting to protect their children, and it might be an easier decision with this vaccine, especially since it's been tried in another population. There's also a desire for some parents to get it first for their kids and contribute to science along the way.”

Unlike the original vaccine trials, researchers aren't looking for efficacy, since that's already been proven. With children, they are trying to determine the right dosage, monitoring for side effects and making sure the vaccine is performing as well as it did in adults, the doctors said.

“It can be tough to find children for research studies and trials,” said Dr. Cheryl Lefaiver, director of the Advocate Center for Pediatric Research at the Advocate Aurora Research Institute. “But because there's such a need for this to bring an end to the pandemic and the heightened awareness of the campaign, that's probably why you're seeing more parents volunteer their children.”

Most children in the research trials have to give their permission to participate, too, Lefaiver said.

“It's necessary to take that in mind from an ethical perspective,” she explained. “For most studies, children 7 and up have to give their assent to participate so they have a say in what's happening to their bodies.”

And while children seem to have fewer significant negative health outcomes from COVID-19 infections, it's important to vaccinate them for other reasons, the doctors said.

“Anywhere the virus is able to spread, it can mutate,” Heald-Sargent said. “These mutations could develop in children and escape to the adult population, which might not be protected from the next variant.”

Also, variants of the virus are starting to affect children in other parts of the world. According to a report published in the British Medical Association's weekly journal, the U.K. COVID-19 variant is infecting Israeli and Italian children at much higher rates than during other surges those countries experienced.

“The U.K. variant is more severe and there's more evidence of that,” Landon said. “If children are left unvaccinated they become a reservoir for the virus.”

Heald-Sargent noted that decades of research on infectious diseases has shown that “protecting children from infection has been proven to protect adults. That's what the science has shown.”

Ultimately, children as young as six months could be approved for the vaccine, doctors said.

There's also evidence, Landon said, that newborns of mothers who had the virus or were vaccinated will have antibodies to fight against the virus from the moment they take their first breath. However, researchers still don't know how long those antibodies last, which could mean those children will require booster vaccines.