sshepard/iStockBy ANNE FLAHERTY and SOPHIE TATUM, ABC News

(ATLANTA) — Teachers and students can safely return to the classroom, even in areas with high rates of viral transmission if certain mitigation steps are taken, according to new guidance released Friday by the Centers for Disease Control and Prevention.

The “operational strategy” relies on four color-coded “zones” based on the prevalence of community spread — blue, yellow, orange and red. Depending upon the zone, the CDC guidance suggests how school districts in that area can reopen safely.

For example, in a “red zone” where COVID-19 cases are high, the recommendation is that schools stay virtual or open on a hybrid basis to allow for social distancing among students and staff. But returning full time could be done safely if the schools regularly test teachers and staff even if they don’t show symptoms.

The CDC recommendations, while not binding, are the first federal guidelines that spell out specifically how a district could reopen based on conditions in their area.

Previously, the CDC had issued guidance that suggested only how to mitigate risk — requiring masks and encouraging social distancing, for example. But the previous guidelines did little to resolve long-running disputes among local officials, parents and teachers’ unions about how far to go before returning to in-person classes.

CDC Director Rochelle Walensky said a key part of the strategy will be “layering” mitigation strategy with priority given to universal mask wearing and allowing for six feet of social distance or assigning kids to cohorts. The plan says teachers or students do not need to be vaccinated before schools reopen, but suggests prioritizing teachers.

Walensky said it’s critical for communities to recognize the “shared responsibility” in keeping COVID-19 levels low so schools can operate safely.

“I want to underscore that the safest way to open schools, is to ensure that there is as little disease as possible in the community,” she told reporters on Friday.

The recommendations also are a nod to educators who for the past year have expressed intense fear over returning to the classroom without more specific instructions on how to do so safely.

Walensky said the recommendations were based on the “best-available science” that in-school transmission remains rare. But the suggestions will not be used to shut down schools that don’t follow the guidelines.

“I want to be clear. With the release of this operational strategy, CDC is not mandating that schools reopen. These recommendations simply provide schools a long-needed roadmap for how to do so safely under different levels of disease in the community,” she said.

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