The CDC introduced a phased approach that's broken down into four color-coded zones that base reopening on the county's level of community transmission.
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"Enabling schools to open and remain open is a shared responsibility," said CDC Director Dr. Rochelle Walensky.
In order for that to happen, Walensky stressed five key mitigation strategies need to be followed.
- Correct use of masks (priority)
- 6 feet of social distancing (priority)
- Hand washing
- Clean facilities
- Use of diagnostic contact tracing
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"I want to underscore that the safest way to open schools is to ensure there is as little disease as possible in the community," Walensky said.
The CDC is recommending counties track the rate of transmission following these four color coded reopening zones. The zones indicate whether schools can offer in-person instruction based on a county's number of new cases per 100,000 people.
Blue and yellow translate to lower/moderate transmission, whereas orange and red translate to substantial/high transmission resulting in virtual-only instruction for middle and high schools.
"That was a big disappointment," said ER Dr. Jean Noble, who leads UCSF's COVID Emergency Response.
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Noble says the CDC should have delinked community prevalence from dictating school reopening.
"Our latest studies really show that schools can be operated safely regardless of the amount of COVID circulating in the community," Noble said. "The other big disappointment is there's no mandate here."
Noble spent months researching COVID transmission in schools - including two major studies in North Carolina and Wisconsin. Without a mandate, she's concerned schools won't make the change to in-person instruction.
"Kids were back in school when positivity rates were up to 40 percent and there were still only seven school-based transmissions over a three-month period," said Noble. "We can enforce universal masking and be safe."
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The CDC encourages vaccinating and weekly testing for teachers and staff, but doesn't deem either essential to reopen.
Meanwhile, as concerns escalate over evolving COVID variants, Wolensky says it's possible guidance could change if transmission moves past the red zone.
"If we get there, we may need to revisit this again," she added.
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