On April 11, public schools in Providence, R.I, made face masks optional instead of mandatory for students and teachers—celebrating the move as a “positive milestone” brought about by declining COVID-19 cases among students and community support for a more lenient policy.
Just over a month later, Providence is one of several school districts requiring masks again in response to rising COVID-19 cases, part of a nationwide spike attributed to the highly contagious Omicron subvariants.
The Providence school district tracked about 60 COVID-19 cases per day last week among staff and students—a dramatic increase from a low of about 10 cases per day in March and early April, according to district data.
“The additional mitigation layer of masking will help us manage this new COVID surge and keep more students in the classroom where they learn best,” Javier Montañez, superintendent of Providence schools, said in a statement on Monday.
Philadelphia schools also resumed a mask mandate “to help protect everyone’s health and well-being as COVID-19 case counts continue to rise in the Philadelphia area,” superintendent William Hite said in a statement. And Brookline, Mass. reinstated an indoor mask mandate in all town-owned buildings, including public schools. The decision came after public health officials compared COVID-19 cases in Brookline public schools to cases in other Massachusetts school districts that had maintained mask requirements and concluded that “a temporary reinstatement would be an important mitigation measure to limit disease spread and reduce disruptions due to student and staff absenteeism.”
Boston public schools, for example, have maintained a mask requirement. City health officials said they would recommend lifting the school mask mandate once daily COVID-19 cases in the city fall to 10 new cases per 100,000 residents. The positivity rate currently stands at 54.5 new cases per 100,000 residents.
But overall, a small percentage of schools have reinstated mask requirements thus far. Just 12 of the country’s 500 largest school districts (2.4%) are requiring masks as of Tuesday, according to a tracker by Burbio, which aggregates school and community calendars and has been monitoring districts’ pandemic policies.
These shifts in school policy come as COVID-19 infections and hospitalizations have increased in many parts of the U.S. At a briefing on May 18, federal health officials said about one third of people in the U.S. live in areas with “medium or high” levels of COVID-19 spread, and should consider masking indoors.
In those areas with high risk, CDC Director Rochelle Walensky said, “we urge local leaders to encourage use of prevention strategies, like masking in public indoor settings and increasing access to testing and to treatment.”
As some schools bring back mask requirements, they’re hoping to prevent transmission and to limit further disruption from school closures or staff absences.
“Wearing masks continues to be a really good, low-cost, pretty low-burden exercise, especially when it is applied in a targeted manner, potentially like a school-based setting,” says Brandon Guthrie, an epidemiologist at the University of Washington, who has written about pandemic safety measures within schools. “It’s a reasonable thing for schools that don’t want to have transmission linked to school settings to use masks as an added level of protection, partly to protect the health of their students and their families, but also to reduce just the disruption to schools.”
School mask requirements have been controversial since the beginning of the pandemic, prompting lawsuits on either side of the issue. Some parents opposed to mask mandates have argued the requirement amounts to government overreach, while parents of children with disabilities or medical conditions that put them at greater risk of becoming very sick if exposed to COVID-19 have argued they cannot safely attend school when other children are unmasked. They say eliminating mask mandates violates the rights of students with disabilities to access public education.
Surveys have shown that public opinion of mask requirements is divided along political lines. In February, 66% of Democrats said K-12 schools should require all students and staff to wear masks, while 78% of Republicans thought schools should not have any mask requirements at all, according to a Kaiser Family Foundation poll.
Given that level of polarization, in places where there is likely to be a strong backlash to reinstating mask mandates, Guthrie says it might not be effective for schools to push for universal masking at this time.
“We need to be thoughtful about promoting preventative measures that are going to be the most effective at the least cost,” Guthrie says, noting that in communities where there has been strong opposition to mask mandates, it might be more worthwhile to try to get more people vaccinated and boosted, instead of reigniting the battle over masks. Studies have shown that vaccines offer protection against severe disease caused by COVID-19.
“It is clearly helping to significantly reduce the burden of hospitalization and deaths,” Guthrie says, of vaccination against COVID-19. “And ultimately, from a public health perspective, those are the things that matter most.”
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Write to Katie Reilly at Katie.Reilly@time.com