Ventilation and mask rules in schools reduce COVID cases, study finds

Elementary schools that improved their ventilation systems and required teachers and staff to wear face masks reported significantly fewer cases of COVID-19, according to a study conducted by the Centers for Disease Control and Prevention and the Georgia Department of Public Health. 

“Requirements for universal and correct mask use among teachers and staff members and improved ventilation are two important strategies that could reduce SARS-CoV-2 transmission as schools continue, or return to, in-person learning,” the study, published Friday, stated. 

The study compared K-5 schools in Georgia that took these preventive measures with similar schools that didn’t, from November 16 through December 11, 2020. Schools that required teachers and staff to wear face masks reported 37% lower COVID-19 incidence, according to the study. 

Schools that said they used one or more methods to improve ventilation had 39% lower incidence. In schools that did so by opening windows or doors or using fans, COVID-19 incidence was lowered by 35%. Schools that used those ventilation measures plus an air filtration system lowered it by 48%. 

The study’s authors noted that the installation of air filtration and purification devices may be more difficult in communities with fewer resources. “However, improvement can be made through dilution methods alone,” the report said. “Ventilation can be improved in simple, cost-effective ways by keeping doors and windows open and using fans to increase air flow from open windows.” 

The study also looked at factors including providing teachers with flexible medical leave, spacing desks in classrooms six feet apart, implementing more handwashing stations and using barriers on all desks. 

“Multiple strategies should be implemented to prevent transmission of SARS-CoV-2 in schools,” the authors wrote.

The study found no statistically significant difference in schools that required mask-wearing for children compared to schools where it was optional for kids.

Despite more states dropping mask mandates following guidance from the CDC which said fully vaccinated people no longer need to wear them in many instances, the report still said that mask-wearing in elementary schools is “critical” for preventing COVID-19 transmission. 

“Universal and correct mask use is still recommended by CDC for adults and children in schools regardless of vaccination status,” the report stated. 

But on Tuesday, Texas Governor Greg Abbott issued an executive order banning mask mandates in public schools statewide.

“Texans, not government, should decide their best health practices, which is why masks will not be mandated by public school districts or government entities,” Abbott said in a statement. “We can continue to mitigate COVID-19 while defending Texans’ liberty to choose whether or not they mask up.”

Nationwide, 97% of schools are now open in person either full- or part-time, according to the president of the American Federation of Teachers, Randi Weingarten. 

“The safety protocols have really worked, but more than anything else has been the vaccines, and with all of that, that’s why we said full speed ahead for September,” she said in a recent interview with CBSN. 

Pfizer’s COVID-19 vaccine has been authorized for young people age 12 and up, but not for younger children. So far, the CDC says more than 1.3 million adolescents ages 12-15 have gotten at least their first dose.