Several measures to mitigate Covid-19 – including improving ventilation, requiring adults to wear face masks, and taking frequent surveillance tests – can help keep schools open and students safe, according to two new studies.
The studies, released on Friday, come as many school districts work out their plans for the fall. They also follow guidelines from the Centers for Disease Control and Prevention that all schools teaching students from kindergarten through 12th grade will continue until the end of the 2020-2021 school year following the agency’s latest move to admit vaccinated people Implement guidelines for wearing masks should not use masks indoors. The agency also upheld its proposals to monitor physical distancing and test for coronavirus infections.
In one of the new studies, researchers from the CDC and the Georgia Department of Public Health surveyed 169 elementary schools in Georgia that offered face-to-face learning last fall. The group asked schools about their pandemic responses and collected data on the coronavirus cases discovered between November 16 and December 11 before vaccines were used in the United States.
The researchers found that the incidence of the virus in schools that had improved their ventilation – by opening windows or doors or using fans – was 35 percent lower than in schools that did not use these practices. In schools that combined better ventilation with air filtration – for example through the use of HEPA filters – the fall rates were 48 percent lower.
The researchers found that all teachers and staff had to wear masks to reduce the incidence of the virus by 37 percent. Schools that required students to wear masks had a 21 percent lower incidence of the virus, but that reduction was not statistically significant, the scientists found. This may be due to the fact that adults are more likely to transmit the virus than children, or simply to a small sample size.
“Since the universal and correct use of masks can reduce SARS-CoV-2 transmission and is a relatively inexpensive and easy to implement strategy, the results of this report suggest that the universal and correct use of masks is an important Covid-19 -Prevention strategy in schools is a multi-component approach, ”write the researchers.
A second study, conducted by researchers from the Utah Department of Health and the University of Utah, tracked the implementation of two coronavirus screening programs in state schools. A program that ran in January 2021 allowed schools with outbreaks to conduct school-wide testing instead of switching to distance learning.
“The schools could either do what they did the fall, switching to remote control for two weeks to break the chains of transmission, or they could test all of them,” said Dr. Adam Hersh, one of the study’s authors and a pediatric infectious disease expert at the University of Utah. “And those who tested negative could return to face-to-face learning, and those who tested positive would obviously be isolated.”
In a second testing program, students had to be tested for the coronavirus every 14 days in order to participate in sports or other extracurricular activities. Both initiatives relied on rapid antigen tests, which are less sensitive but cheaper and faster than standard PCR tests.
That year, between January 4 and March 20, 28 high schools in the state reported sizeable outbreaks. Fifteen schools decided to switch to distance learning for two weeks, while the other 13 decided to run surveillance tests instead. Of the 13,809 students who were tested as part of this screening, only 0.7 percent were positive, the scientists reported. All 13 schools remained open.
“This is a huge achievement from a public health perspective,” said Kendra Babitz, coronavirus testing coordinator for the Utah Department of Health and one of the study’s authors. “Testing is and should be a mitigation strategy that schools use to prevent the transmission of SARS-CoV-2 in schools,” she added, referring to the virus that causes Covid-19.
Over the winter, 95 percent of school sports events took place on schedule, the researchers found, although they didn’t compare that number to a control group of schools without screening programs. “This is similar to what happens in the normal season,” said Dr. Hersh. “The show could go on.”