The Centers for Disease Control and Prevention on Friday relaxed physical distancing requirements for children in school, from 6 feet to 3 feet — a change aimed at allowing more students to be inside classrooms.
The recommendations come with a few caveats. Teachers and other adult school staff must still adhere to the 6 feet guidelines, and face coverings remain mandatory.
"These recommendations are specific to students in classrooms with universal mask wearing," CDC director Dr. Rochelle Walensky said during a briefing Friday.
Multiple studies have shown increases in depression and anxiety among children during the pandemic. And a survey from NBC News and Challenge Success, a nonprofit affiliated with the Stanford Graduate School of Education, found lower stress levels among students who have been able to spend time in the classroom, compared with peers who are virtual learning exclusively.
"The benefits of in-person instruction are well-recognized," Walensky said. "School should be the last place to close and the first place to open."
For elementary school students, the CDC now recommends a physical distance of 3 feet. The same rules apply to middle and high school students, unless they live in an area where Covid-19 is spreading at a high rate, in which case distances of 6 feet should be maintained.
And for all students, no matter the rate of community spread, distances of 6 feet should still be followed in settings where masks cannot be worn, such as lunchtime, the CDC said, as well as during activities like choir, band or intense sports that involve greater exhalation. Those activities should take place outdoors or in large, well-ventilated spaces when possible.
Dr. Robert Murphy, a professor of infectious diseases at Northwestern University Feinberg School of Medicine, said that for most scenarios, a distance of 3 feet "is the biggest bang for your buck" when it comes to reducing the spread of SARS-CoV-2, the virus that causes Covid-19.
Murphy noted several studies that provide evidence for the recommendation, including one published last week that compared rates of Covid-19 case rates among students and staff in Massachusetts public schools with different physical distancing requirements. Rates were similar whether the districts required physical distancing of 3 feet or 6 feet.
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. The World Health Organization also recommends a physical distance of 3 feet.
On Friday, the CDC also published a report on elementary schools in Utah that did not have space to adhere to the 6 feet distancing rule.
"Despite high community incidence and an inability to space students' classroom seats more than 6 feet apart," the researchers wrote, "this investigation found low SARS-CoV-2 transmission and no school-related outbreaks in 20 Salt Lake County elementary schools." Mask use was robust, at 86 percent.
The study concluded that the modified policy "resulted in over 1,200 student in-person learning days saved."
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For now, the 3 feet guidance is limited to children in school. But it poses an intriguing question for the rest of society, eager to resume normal activities and perhaps get back into an office setting.
Walensky said, however, that there is no scientific evidence to suggest reducing recommended distances between adults would be safe or effective.
"Our school studies have shown that when young children are masked, the distance of 3 feet is, in fact, safe and has a lower transmission risk," Walensky said during Friday's briefing. "For adults, we don't have that evidence, so we're continuing with the 6 foot guidance."
Meanwhile, children are in a controlled environment when in school, with teachers monitoring.
"If they're told to stay 3 feet away, if they're told to wear masks, they do it," Murphy said. "That's the thing about going to school. Kids follow the rules."