The director of the US Centers for Disease Control and Prevention on Sunday emphasized the need for masking and other mitigation measures in order to reopen schools safely.

According to a story reported on by WHDH/7 News Boston, the director stressed “we have work to do” as teachers, students, and parents continue to struggle with Covid-19’s impact on education.

Dr. Rochelle Walensky told CNN’s Jake Tapper on “State of the Union” when pressed about why schools across the country haven’t reopened, "We have work to do, especially when the country remains in the red zone of high community transmission. As that transmission comes down we’ll be able to relax some of these measures, but the real point is to make sure that the science is consistent with our guidance, which is consistent to say until we can ensure that we have all those measures happening that there would — schools wouldn’t be safe."

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Walensky cited the CDC’s latest Morbidity and Mortality Weekly Report — which showed that around 60% of high school and middle school students are reliably masked. “This has to be universal,” she said, in addition to practicing six feet of distancing and other mitigation measures.

Walensky’s comments come as schools across the US debate how to reopen safely, with some combining a mixture of virtual and in-person learning, and as the push to prioritize teachers for vaccinations increases.

The CDC on Friday released its long-awaited guidelines for reopening schools that focus on five key Covid-19 mitigation strategies: the universal and correct wearing of masks; physical distancing; washing hands; cleaning facilities and improving ventilation; and contact tracing, isolation and quarantine.

Vaccines and testing are not among the “key” strategies the agency lays out, calling them “additional layers” of Covid-19 prevention.

About 99% of children in the US live in a county considered a “red” zone with high levels of Covid-19 transmission under the CDC's new opening guidance, according to a CNN analysis of federal data.

The CDC guidelines recommend virtual learning for middle and high schools and hybrid learning or reduced attendance for elementary schools in these high transmission zones.

Nearly 73 million children — about 99% of the US population under the age of 18 — live in such a “high transmission” community, defined by the CDC as a county where there were at least 100 new Covid-19 cases per 100,000 people or a test positivity rate of at least 10% during the past seven days.

Fewer than 100,000 children in the US live in a county considered “low” or “moderate transmission” where the CDC recommends K-12 schools open for full in-person instruction. Most of those students live in Hawaii or Washington.

Walensky said that while vaccinating teachers is not a prerequisite for reopening schools, current CDC guidance does specify that those who are at higher risk should have virtual options.

Guidance from the CDC’s Advisory Committee on Immunization Practices puts teachers in the 1B category, which is the same as people over age 75.

“I’m a strong advocate of teachers receiving their vaccinations, but we don’t believe it’s a prerequisite for schools to reopen,” she said.

There is much more to the story. Check it out at WHDH/7 News' website here.

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