The Centers for Disease Control and Prevention last week stated 90% of Americans no longer need to wear face masks indoors, including in K-12 schools.

Yet through mandates or local guidance, young children — who face the lowest risk of COVID complications — are still being forced to mask for hours a day across the country, including in New York, California and DC and its suburbs, in some cases even outdoors.

In America’s great unmasking, 2- to 5-year-olds are excluded even as the harms from masking them continue to come to light.

Since early in the pandemic, the American Academy of Pediatrics and the CDC have recommended that children 2 years and older wear masks. That’s in stark contrast with the World Health Organization, which states that based on their “psychosocial needs and developmental milestones,” kids “aged 5 years and under should not be required to wear masks.”

Many places in Europe, including the United Kingdom, France, the Netherlands and all of Scandinavia, didn’t even mask elementary-school children, and there is no evidence of increased outbreaks or community spread. Our stringent masking policies haven’t led to our youngsters demonstrating better COVID health outcomes, either.

Many are reluctant to take masks off children because COVID vaccines are not yet approved for those 5 and younger. (Though in some odd phrasing, the CDC says it “recommends universal indoor masking” in early care and education programs “for those ages 2 years and older, regardless of vaccination status.”)

Yet unvaccinated children are at lower risk of COVID complications than vaccinated adults.

For the week of Feb. 26, CDC data showed the hospitalization rate for kids 0 to 4 years with COVID was 2.1 per 100,000 people. Compare that with the rates for adults, the vast majority of whom are vaccinated: For 30- to 39-year-olds, it was 2.0 per 100,000; for 50-64, 3.7; 65-and-up, 10.8.

And of that small group of hospitalized young children, up to half are admitted incidentally with COVID, not because of COVID.

In other words, children have been the least affected by COVID but continue to face the most stringent restrictions.

Though science is lagging on the effects of this unprecedented long-term masking, indications are that the harm to preschool-age children is likely vast, ranging from speech delays to difficulty forging friendships. This age group more than any other heavily relies on nonverbal feedback for critical development, particularly emotional mimicry and social referencing.

Parents have heartbreaking stories of their young children’s mask experiences. Preschool teachers aren’t catching severe allergic reactions right away because they can’t see a child’s face to identify an early sign, redness of mouth. A child vomits in his mask only to be told to put on a new mask immediately. Asthma and hearing loss haven’t qualified for mask exemptions.

When Brooke’s daughter is nervous or scared, she tends to mouth what she needs to say instead of saying it out loud. In a mask, no one has any idea she is trying to communicate with them, likely heightening her anxiety about a new environment or situation and eroding trust with those she relies on to keep her safe.

These experiences can have lasting effects. Children do not get a do-over of this critical time in development.

And the harmful disruptions to a child’s life don’t always manifest immediately. As with any public-health measure, the burden of proof should be on the intervention — the benefit to populations should outweigh the harms. Right now, the benefits of child masking are unproven, and the harms are just beginning to be understood and are unfolding in real time.

While masking up seemed prudent in early 2020, we’re at a different stage of the pandemic, with vaccines and therapeutics to protect the most vulnerable and less virulent strains. Continued restrictions on young children will result in further detrimental effects on language, social skills and mental health.

It’s time for public-health authorities to acknowledge the science. Without CDC and AAP leadership in changing their guidance, many early-childhood education settings are reluctant to change policies.

One day, we’ll look back and see the United States as the country that put policies in place that harmed children to provide uncertain benefit to adults. We must remove the masking guidance for all children in America and let kids have the childhood they deserve.

Dr. Jessica Hochman is a board-certified pediatrician. Brooke Smitherman Schmidt is a mother of two and a founder of Save the Tots Virginia, a nonpartisan group advocating mask choice and sensible COVID-19 policies.