While children are less likely than adults to develop severe illness from COVID-19, they are known to contract and spread the disease asymptomatically. Fauci has estimated that the herd immunity threshold for COVID-19 is between 70 percent and 85 percent of the population, meaning that those vaccinated or exposed to the virus reaches a high enough level to prevent its further spread. Given that almost a quarter of the U.S. population is under the age of 18, achieving herd immunity will require that at least some children be vaccinated.

As of Feb. 1, over 31 million Americans, most over the age of 65, had received at least one dose of a COVID-19 vaccine. In the coming weeks, the vaccine rollout is expected to extend beyond health care workers and the elderly, yet neither of the two vaccines has yet been approved by the Food and Drug Administration for children. Pfizer’s vaccine has been cleared for people 16 years and older, while Moderna’s is approved for those 18 years or older.