WASHINGTON — The U.S. may be weeks away from getting its first coronavirus vaccine approved for adults, but many parents and doctors wonder when children will be able to benefit from the protection it offers.
Experts have said that adults in the general public likely won't get vaccinated until spring, and kids might have to wait even longer — possibly till the end of 2021.
That's because kids weren't involved in COVID-19 vaccine clinical trials until two months ago, when pharmaceutical company Pfizer and its partner BioNTech recruited 16 and 17-year-olds. In October, the companies received approval to enroll kids between 12 and 15-years-old.
To date, Pfizer/BioNTech's vaccine is the only candidate that's being tested in children.
Other companies in line to get their COVID-19 vaccine candidate approved have said they also plan to start pediatric trials when their data on adults prove safe.
But just like for adults, it will take months for researchers to learn if a vaccine is safe for youngsters, who have different immune systems than older individuals.
"We wouldn't start injecting 5-year-olds before we knew what this vaccine did in adults," Dr. William Schaffner, professor of preventive medicine and infectious diseases at the Vanderbilt University School of Medicine in Nashville, told ABC News in October.
Dr. Sean O'Leary, vice chair of the American Academy of Pediatrics Committee on Infectious Diseases, told the outlet that while children aren't as affected by the disease as adults, they still play a role in spreading it.
"We certainly know that children can get it and can spread it," O'Leary said. "And so I think there is certainly urgency across the board for children to get a safe and effective vaccine."
A study published in July found that children younger than 5 years old can carry up to 100 times more of the virus in their noses than older children and adults, McClatchy News reported. Another paper released in the same month found that school-aged children can spread the virus just as well as adults do.
A likely scenario is that teenagers will get vaccinated before younger kids, according to Dr. Robert Frenck, who's in charge of the Pfizer vaccine trial for children at Cincinnati Children's Hospital Medical Center.
Frenck told Seattle's KIRO7 that his hospital is planning on enrolling 600 teens between 16 and 17 years old and 2,000 kids between 12 and 15 years old.
"I don't think it's really going to be that far behind the adult data because we're looking at different outcomes. We're not looking to enroll 30,000 adolescents. We're looking to enroll in the hundreds," Frenck told the outlet. "I don't think it's overly optimistic to say we could have a vaccine available at least for teenagers and maybe younger before the next school year."
He told The Associated Press in October that vaccinating teens first makes sense because they usually receive "adult-sized doses" of other vaccines.
"If we immunize adolescents — and potentially move down into younger children — we're going to have the effect of keeping those children from getting infected," Frenck told the AP. "But then also they don't bring the infection home to parents and grandparents."
Dr. Evan Anderson, a pediatric infectious disease specialist at Children's Healthcare of Atlanta, told the same outlet that younger children need their own testing because they have more "robust" immune systems that may need different doses or show different reactions.
Still, "children deserve the same level of prioritization," Dr. John Brownstein, an epidemiologist at Boston Children's Hospital, told ABC News.
"I mean, clearly we want to focus on those that are going to have the most severe impacts of the virus, but children are still critical and especially as we're trying to keep kids in school and bring them back to a normal life, having a vaccine is so important for that return to normal," he said.
