World Views | Schools can reopen safely – an epidemiologist describes what works and what’s not worth the effort

Just when schools were getting ready to reopen for the new school year, cases of COVID-19 started surging in the United States, driven in large part by the more contagious delta variant. School administrators around the country are working to bring students back into the classroom safely, while still providing kids an enriching learning environment.
As an infectious disease epidemiologist at the University of Washington, I have spent the past year and a half working with a group of epidemiologists and health professionals to collect, review and evaluate the scientific evidence about COVID-19 for state and local public health agencies.
Our group concluded that vaccines and masking work well for preventing COVID-19 outbreaks in schools, but other strategies like plexiglass barriers and temperature checks are probably not worth the effort.
A COVID-19 vaccine is the single most important tool for preventing COVID-19 in schools, as well as nearly everywhere else. All the vaccines currently authorized for use in the U.S. have been shown to help prevent infections and protect against moderate and severe disease. Some variants, such as delta, may be more likely to cause breakthrough infections, but vaccinations have shown protection against symptomatic disease caused by delta.
The more people in a school who are vaccinated, the lower the risk of an outbreak in the school and the lower the likelihood that someone will develop severe disease if infections occur. COVID-19 vaccines are currently available to anyone age 12 or older, and it is possible that at least one of the vaccines will be authorized for younger school-age children in the later months of 2021 or early in 2022.
Masks are important, too. Not everyone in a school can be or will choose to be vaccinated, and there is also a risk of breakthrough infections, especially from the delta variant. Masks reduce the risk of an infected person spreading the virus and provide some protection for the wearer against becoming infected. During the past academic year, mask-wearing was shown to reduce the spread of COVID-19 in schools. Masks also don’t disrupt the school day in the way that other measures might, such as keeping students in fixed cohorts or shortening the school day for split shifts.
It’s also probably not worth testing everyone on a regular basis. Frequent testing is expensive, and real-world examples and mathematical models indicate that routine asymptomatic testing for COVID-19 in schools provides little additional benefit beyond widespread vaccination and masking.
Students should wear masks whenever they are not actively eating. As challenging as it is to manage a rambunctious lunchroom, shouting, singing and loud talking spread more virus and should be discouraged, especially without masks. And good ventilation, particularly in spaces where people are eating, is important.
Students also need to keep their distance from one another while they eat. Schools may consider having more lunch periods, having children eat in their classrooms, or using other spaces in the school to reduce crowding.
The strongest driver of COVID-19 in children, teachers and families is not school – it’s the level of community transmission.
Given what we currently know, schools can continue to operate in person without widespread transmission linked to schools. When community transmission is high, schools should take extra care to stick to their prevention strategies. But the main way to protect students is to stop the spread of COVID-19 outside of school.
COVID-19 never fails to provide new surprises. Many aspects of the next school year remain unknown, but by learning from what worked and didn’t work over the past school year, we have evidence that in most situations students can safely return to school in person as long as these layered prevention measures are put in place and adhered to.
Brandon Guthrie, University of Washington, MDT/THE CONVERSATION
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