The Centers for Disease Control and Prevention is looking into whether 6 feet of distance is necessary to keep students safe at school — or if 3 feet will suffice.
The debate carries major implications for school reopenings: The current CDC guidance recommends maintaining 6 feet of distance between students, severely limiting the number of people who can safely fit into each classroom.
CDC Director Dr. Rochelle Walensky was grilled about the issue during a Wednesday subcommittee hearing of the House Committee on Energy and Commerce. The subject of the hearing was vaccine distribution.
Rep. Cathy McMorris Rodgers, R-Wash., pressed Walensky about when the CDC would provide guidance to relax physical distancing requirements in schools.
“Yes or no, if people are masked, is it safe and more practical to open schools with 3 feet of distance?” McMorris Rodgers asked Walensky.
Walensky responded that the science on the matter continues to evolve. Indeed, a growing body of evidence suggests that 3 feet may be acceptable.
One study, published last week in the journal Clinical Infectious Diseases, compared the rates of Covid-19 cases among students and staff in Massachusetts public schools with different physical distancing requirements.
Among more than 240 school districts studied, Covid-19 case rates were similar whether the districts required physical distancing of 3 feet or 6 feet.
The research concluded: “Lower physical distancing policies can be adopted in school settings with masking mandates without negatively impacting student or staff safety.”
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And a review of research published in The Lancet last year supported physical distancing of at least 3 feet, provided that people use proper face coverings.
Mask-wearing is key. Walensky noted, in response to McMorris Rodgers’ questions, that a smaller distance would require 100 percent mask compliance. A CDC survey published in February found that just 65 percent of middle and high school students said their classmates wore masks at all times.
Dr. Robert Murphy, a professor of infectious diseases at Northwestern University Feinberg School of Medicine, said that as long as people are not singing or shouting or otherwise emitting a lot of respiratory droplets, a physical distance of 3 feet appears to be safe, as long as people are masked.
“Is 6 feet better? Yes!” Murphy said. “But so is 100 feet.”
Walensky said additional studies on the matter are pending and that the CDC expects to update its guidance on physical distancing in schools “soon.”