NEW YORK — When will children be able to get COVID-19 vaccines?

It depends on the child's age, but some teenagers could be rolling up their sleeves before too long.

The Pfizer vaccine already is cleared for use starting at age 16. That means some high schoolers could get in line for those shots whenever they become eligible in their area, either because of a medical condition or once availability opens up. 

Pfizer and Moderna both have completed enrollment for studies of children ages 12 and older, and expect to release the data over the summer. If regulators clear the results, younger teens likewise could start getting vaccinated once supply allows. The Moderna vaccine is currently cleared for people 18 and older.

Researchers started with older children because they tend to respond to vaccines most similarly to adults. Testing even younger groups is more complex, because they may require a different dose or have differing responses. 

"Children are not just small adults," said pediatrician Dr. James Campbell of the University of Maryland School of Medicine. "The younger you get, the higher the odds are that things could be different."

Children develop serious illness or die from COVID-19 at much lower rates than adults, but can still spread the virus.

"There's no question: we do want to immunize children," said Drexel University pediatrics professor Dr. Sarah Long.

Pfizer and Moderna expect to start studies in children 11 and younger later this year.

"It's unlikely we could get community protection without immunizing children," Long added. "This is the lynchpin to getting everything back to some kind of normalcy."