School can open safely during COViD, the latest evidence shows.

Since the earliest days of the pandemic last March, debate has raged over whether schools are a significant source of COVID-19 transmission and should remain closed—or if in-person learning can, and should, continue with safety protocols in place. Experts have expressed increasing concern over the downsides that prolonged virtual instruction might pose for academic and social development in children—especially kids in disadvantaged communities who were already struggling before the pandemic. Now, more than a year after schools around the country first shut down, many experts agree they can remain open safely if they implement measures such as mask wearing, physical distancing and good ventilation.

Studies of school districts in states such as Florida, Utah and Missouri found that in-person instruction did not lead to a noticeable spike in COVID cases. The Centers for Disease Control and Prevention recently updated its guidelines to say that three feet of distancing (as opposed to the six feet recommended earlier) is sufficient to limit transmission among elementary school children—and among middle and high school kids when community transmission levels are low—as long as masks are worn. The guidelines also emphasize the importance of universal mask wearing and good ventilation and recommend having “cohorts” of students that spend the day together and maintain distance from other cohorts. About 80 percent of teachers and school staff members have now received at least one vaccine dose, according to the CDC. Although the vaccines are not yet available to children, clinical trials involving them are underway.

Evidence suggests that the benefits of having kids in school—with precautions in place—strongly outweigh the risks, especially now that most teachers have been vaccinated. “The goal has to be to get kids back to in-person learning,” says Sara Bode, a member of the American Academy of Pediatrics (AAP) Council on School Health’s executive committee. “There has been a mounting body of evidence over the past year of schools being able to put mitigation strategies into place and not seeing much student-student spread. It can be done, and it can be done effectively.”

A layered approach is essential when it comes to lowering the COVID transmission risk in schools, says Greta Massetti, co-lead of a CDC task force on the agency’s response to COVID, including school guidance. “Young children are going to pull their masks down sometimes or not wear them properly or not wash their hands,” she says. So “you’re not relying on any one layer. It’s the ‘Swiss cheese model.’” Some epidemiologists have used this metaphor to describe imposing multiple public health interventions at once: each “slice” has “holes,” but stacked together, they improve protection.

Perhaps the most important measure schools can take to keeps kids and staff safe is the universal use of face masks at all times, except when eating or drinking. The CDC recommends that students maintain at least six feet of physical distance when masks are off. “Many schools are doing very creative things during mealtimes: establishing routines so students keep their masks on until they are ready to eat, then putting them back on; seating kids facing in the same direction; staggering lunch schedules; and having half the class go to the cafeteria and half eat in the classroom,” Massetti says. Studies have shown that even young children can wear masks properly. One study in Wisconsin found that more than 92 percent of students reported wearing a mask consistently while at school. “Many times, they’re better than adults,” Massetti says. But schools must clearly mandate masks, she adds. “When they make it optional, then nobody wears a mask,” Massetti says.

Masks are also very effective at protecting faculty and staff. “If schools require masking and do hand hygiene, the risk of mortality from driving to work [and having a traffic accident] is higher for an unvaccinated adult than it is from acquiring COVID in school,” says Danny Benjamin, a professor of pediatrics at Duke University School of Medicine. Benjamin and his colleagues co-authored a study of coronavirus transmission in K–12 schools in North Carolina that had in-person classes between mid-August and mid-October, 2020. The study found in-school transmission of the virus was extremely limited, and there were no observed cases of kids infecting adults. Other studies have found similar results in Mississippi, Wisconsin and additional states. “It’s pretty simple: if everybody wears a mask all the time, the risk is low,” Benjamin says. “For us to be keeping schools closed because of the risk of COVID is simply malpractice.”