Corrected: This story previously gave the wrong location for Dr. Ibukun Kalu’s study. The research was conducted in North Carolina.
Corrected: An earlier version of this story misstated the numbers of states with mask mandates in place and those with mandates about to expire. More than a dozen states have mask mandates and some, such as Connecticut and New Jersey, expire this month if not extended.
The big debate about when schools should begin to scale back or do away with universal masking in schools is in full swing now that the spread of the omicron variant is slowing and vaccination rates are rising.
While more than a dozen states have mask mandates in place for schools, some of them, including Connecticut and New Jersey, expire this month if they are not extended. And in the majority of states, mask policies are set at the district level.
That leaves thousands of school districts working to decide how they will use masks for the rest of the school year.
The U.S. Centers for Disease Control and Prevention recommends universal indoor school masking for children and adults over age 2, regardless of their vaccination status. But the World Health Organization advises against masks for those under 6, and the European Center for Disease Prevention and Control suggests the “use of masks when feasible” in schools. The center notes that children are much less likely to have symptomatic COVID-19 and it promotes the use of social distancing and improved ventilation in schools before mask requirements.
The CDC, the Infectious Disease Society of America, and the American Academy of Pediatrics all continue to recommend universal indoor masking in schools, and those guidelines have been the basis for many pandemic-era contract negotiations for teachers and other staff.
“I am not sure that I understand why there is a debate about whether students should still be required to wear masks after vaccination,” said Dr. Tina Tan, a pediatric infectious disease doctor at Lurie Children’s Hospital in Chicago and professor of pediatric infectious disease at Northwestern University.
“The answer is yes,” she continued, “given that not everyone is vaccinated and omicron is very transmissible and can be acquired even if you are vaccinated. Masks provide the extra protection needed to prevent transmission and spread.”
Yet public groups that oppose masking have gained traction in recent weeks, such as a California group calling for a “post-omicron pivot” away from mask requirements. And education workers themselves have called for more transparency in how schools decide on mask policies and whether they take students’ other education needs into consideration. Those are big concerns in New York, for instance, where mask mandates have been set and then rolled back amid ongoing lawsuits.
“If the groundhog sees his shadow, will kids have to mask for six more weeks?” Justin Spiro, a New York school social worker, tweeted on Feb. 2.
Much of that decisionmaking will depend on how long it takes for omicron to recede. Even so, school leaders should start planning longer-term pandemic responses, said Sara Bode, chair-elect of the American Academy of Pediatrics Council on School Health.
“We had hoped that we would be in a [school masking] off-ramp situation right now,” Bode said. “We are probably three or four months off of that still—not necessarily because of the risk to the students themselves but because of the ongoing risk of them carrying it to other people in the community, if you’ve got a high community spread rate.
“That turns into a question of what is the school’s role in thinking about their students versus the broader community,” Bode said, “and the broader community also means whether your teachers are willing to come in if you’re having a high teacher absentee rate.”
District leaders should consider a variety of issues when planning mask policies.
What does research say about the benefits of children wearing masks in schools?
Research that the CDC has cited in support of universal mask wearing in schools has come under sharpcriticism from some doctors. There are no randomized controlled studies of the health effects of mask wearing among children, much less children in schools.
Plus, studies of the COVID policies implemented in schools often suffer from confusion about what approach is having the greatest impact because of the mix of mitigation strategies—such as vaccine mandates, social distancing measures, or proper use of masks—used by both schools that require masks and those that do not.
“The reviewed literature directly evaluating the impact of COVID-19 policies largely failed to meet key design criteria for inference of sufficient rigor to be actionable by policymakers,” found one analysis in the British Medical Journal. “This was largely driven by the circumstances under which policies were passed, making it difficult to attribute changes in COVID-19 outcomes to particular policies.”
For example, one oft-cited study in the journal Science that examined the effects of multiple mitigation strategies found a significant benefit for teacher masking but not student masking, in part because researchers noted that the vast majority of both treatment and control schools required universal masking.
“This is all messy data,” Bode said. “I definitely have to acknowledge, as a physician, the data is difficult to gather, especially as circumstances keep changing.”
“As we’re continuing to gather that data, it’s just difficult to have information for schools to say, ‘right, this is exactly the level of protection you’re afforded with this type of mask in these settings,’” Bode said. “I think that makes it challenging for schools to be able to point to one study to make their decision” on mask policies.
Researchers recommend education leaders consider their mask policies in the same context they generally have been studied: as part of a multipronged strategy.
“COVID-19 mitigation measures—masks, vaccines, distancing, cohorting, et cetera—are not 100 percent effective on their own, but when combined they can work more effectively,” said Chris Bauch, an applied mathematics professor at the University of Waterloo in Ontario, Canada, who models the spread of COVID-19 in schools with different mitigation strategies.
“An individual mitigation measure is like a sieve that lets water through—it helps a lot, but is not 100 percent effective to prevent transmission. But when mitigation measures are combined, like multiple sieves being stacked together, less water will get through—much fewer cases,” Bauch said.
What community issues should education leaders consider?
In many states, triggers for school closures, masking, and other mitigation requirements rely on data on community infection rates, which are currently at the CDC’s highest level nationwide, even as omicron cases have slowed.
“This is a public health problem, not an individual medical problem—much of the benefit of reducing transmission among schoolchildren is in preventing them from spreading it to more vulnerable individuals in their community and family, such as parents and grandparents,” Bauch said.
Bode agreed, and suggested school leaders consider their broader community when determining any mitigation policies. For example, schools that have higher percentages of students with asthma or other respiratory problems, or those in communities with higher populations of elderly or unvaccinated residents, may choose to mask for longer.
Should schools require particular kinds of masks?
The rise of the highly contagious delta and now omicron strains have spurred more debate about what kinds of masks provide sufficient protection. Dr. Ibukun Kalu, medical director of pediatric infection prevention at Duke University Hospital, has been studying school responses to the pandemic in North Carolina. Most of the schools she works with have focused—during the omicron wave—on helping staff and students use better-fitting masks that include multiple layers and filters.
There is significant evidence that N95 and surgical masks protect better overall than cloth masks. In one California study released Feb. 4, the CDC found that people who wore a surgical mask or N95/KN95 respirator mask indoors while in public had lower risk than those who didn’t wear masks of testing positive for COVID-19 from February to December of 2021. That was a period when the alpha and delta strains of the pandemic dominated, though not the significantly more contagious omicron variant.
However, people who wore cloth masks did not see significantly lower risk of infection compared to those who wore no mask at all. The study was based on survey data and did not look at participants’ mask fit or other protection efforts, such as vaccination status or social distancing. Moreover, while the study included children under 18, it did not disaggregate mask benefits by age.
The CDC has recommended N95 or KN95 respirator-style masks as offering the highest protection. But it specifically notes that “although respirators may be available in smaller sizes, they are typically designed to be used by adults in workplaces, and therefore have not been tested for broad use in children.”
Experts said even if respirator masks provide more protection for children, school leaders should prioritize getting students masks that fit well and comfortably. That has led some experts to suggest schools consider making respirator-style masks the norm, but allow them to be optional.
“The best mask for kids is the one they’ll actually keep on over their nose and their mouth,” Bode said. “So, part of this is looking at those practical considerations of kids who have to be in masks all day. If a KN95 isn’t tolerated, it’s not giving you any more benefit.
“I actually think it’s pretty impractical to expect that schools would have students wearing those [respirator] masks all day long at any age” she added.
Does the use of masks in schools affect students’ language and social development?
When the pandemic started, there was virtually no research on the long-term effects of masking on students’ language and social development. But studies in the two years since have shown some concerning trends.
The WHO voices reservations about universal masking of those ages 6-11, specifically because of the “potential impact of wearing a mask on learning and psychosocial development.”
Studies have found masks domuffle speech for listeners, and students are significantly less accurate in hearing sentenceswhen the speaker used a face-obscuring mask, though transparent masks allow better understanding.
Moreover, schools are already expected to face higher rates of hearing, speech, and communication disorders in children, because the pandemic has interfered with or delayed early screening for those learning challenges.
“Long-term mask use doesn’t have zero harm,” Bode noted, but added that masks have been less disruptive to students than more dramatic mitigation efforts, such as closing schools.
“If the alternative is that we’re going remote, that would be, in my mind, a worse outcome,” she said.