To our knowledge, the CDC has performed three studies to determine whether masking children in school reduces COVID-19 transmission. The first is a study of elementary schools in Georgia, conducted before vaccines became available, which found that masking teachers was associated with a statistically significant decrease in COVID-19 transmission, but masking students was not—a finding that the CDC’s masking guidelines do not account for.
A second and more recent study of Arizona schools in Maricopa and Pima Counties concluded that schools without mask mandates were more likely to have COVID-19 outbreaks than schools with mask mandates. Yet more than 90 percent of schools in the “no mask mandate” group were in Maricopa County, an area that has significantly lower vaccination rates than Pima County. This study had other serious shortcomings, including failure to quantify the size of outbreaks and failure to report testing protocols for the students.
The third CDC study found that U.S. counties without mask mandates saw larger increases in pediatric COVID-19 cases after schools opened, but again did not control for important differences in vaccination rates. The CDC has cited several other studies conducted in the previous school year to support its claim that masks are a key school-safety measure. However, none of these studies, including ones conducted in North Carolina, Utah, Wisconsin, and Missouri, isolated the impact of masks specifically, because all students were required to mask and no comparisons were made with schools that did not require masks.
Therefore, the overall takeaway from these studies—that schools with mask mandates have lower COVID-19 transmission rates than schools without mask mandates—is not justified by the data that have been gathered. In two of these studies, this conclusion is undercut by the fact that background vaccination rates, both of staff and of the surrounding community, were not controlled for or taken into consideration. At the time these studies were conducted, when breakthrough infections were much less common, this was a hugely important confounding variable undermining the CDC’s conclusions that masks in schools provide a concrete benefit in controlling COVID-19 spread: Communities with higher vaccination rates had less COVID-19 transmission everywhere, including in schools, and those same communities were more likely to have mask mandates.
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Other studies—not randomized trials—have looked at the effects of masks in schools, and their results do not support pervasive, endless masking at school. A study from Brown University, analyzing 2020–21 data from schools in New York, Massachusetts, and Florida, found no correlation between student cases and mask mandates, but did see decreased cases associated with teacher vaccination. A study published in Science looking at individual mitigation measures in schools last winter found that, although teacher masking reduced COVID-19 positivity, student masking did not have a significant effect.
Even though the first half of this school year was dominated by the highly transmissible Delta variant, the picture in more recent studies looks similar. In Tennessee, two neighboring counties with similar vaccination rates, Davidson and Williamson, have virtually overlapping case-rate trends in their school-age populations, despite one having a mask mandate and one having a mask opt-out rate of about 23 percent. One would expect a quarter of the students opting out of masking to affect transmission rates if masks played any significant role in controlling COVID-19 spread, but that was not the case. Another recent analysis of data from Cass County, North Dakota, comparing school districts with and without mask mandates, concluded that mask-optional districts had lower prevalence of COVID-19 cases among students this fall. Analyses of COVID-19 cases in Alachua County, Florida, also suggest no differences in mask-required versus mask-optional schools. Similarly, the U.K. recently reported finding no statistically significant difference in absences traced to COVID-19 between secondary schools with mask mandates and those without mandates.
Despite how widespread all-day masking of children in school is, the short-term and long-term consequences of this practice are not well understood, in part because no one has successfully collected large-scale systematic data and few researchers have tried. Mental and social-emotional outcomes are hard to observe and measure, and can take years to manifest. Initial data, however, are not reassuring. Recent prospective studies from Greece and Italy found evidence that masking is a barrier to speech recognition, hearing, and communication, and that masks impede children’s ability to decode facial expressions, dampening children’s perceived trustworthiness of faces. Research has also suggested that hearing-impaired children have difficulty discerning individual sounds; opaque masks, of course, prevent lip-reading. Some teachers, parents, and speech pathologists have reported that masks can make learning difficult for some of America’s most vulnerable children, including those with cognitive delays, speech and hearing issues, and autism. Masks may also hinder language and speech development—especially important for students who do not speak English at home. Masks may impede emotion recognition, even in adults, but particularly in children. This fall, when children were asked, many said that prolonged mask wearing is uncomfortable and that they dislike it……….
(THE ATLANTIC)