(CNN) — A study that found teachers — not students — were the probable source of several school-related Covid-19 outbreaks highlights the need to maintain mask and distancing guidelines and to prioritize teachers and school staff for vaccination, US Centers for Disease Control and Prevention Director Dr. Rochelle Walensky said Monday.

The “concerning report,” published Monday, details an investigation of Covid-19 spread in at least six public elementary schools in a Georgia district in early winter, when there was high community spread, the director said.

“The two main reasons for the spread of Covid-19 in these schools were inadequate physical distancing and mask adherence,” Walensky said. “In the schools, physical distancing of at least 6 feet was not possible because of the high number of students in class, as well as because of classroom layouts.”

The findings show how important it is for schools to strictly adhere to the CDC’s five key Covid-19 mitigation strategies, Walensky said. Those strategies are: universal and correct wearing of masks; physical distancing; washing hands; cleaning facilities and improving ventilation; and contact tracing, isolation and quarantine.

“The findings also highlight the importance of scaling up vaccination efforts across the country, including the continued need to prioritize teachers and other school staff for vaccination as part of the frontline essential workers, consistent with the recommendation of the Advisory Committee on Immunization Practices,” she added.

Walensky did not say teachers need to go to the front of the vaccination line. Instead, schools need to work harder to make sure teachers, staff and students wear masks properly and maintain social distancing as possible, she said.

Vaccinations are not among the “key” Covid-19 mitigation strategies the CDC lays out for schools. Instead, the agency calls them “additional layers” of Covid-19 prevention.

Teacher meetings likely fueled spread, study finds

The CDC study looked at 700 school staff members and 2,600 students who participated in in-school learning at eight public elementary schools in suburban Atlanta from December 1 to January 22. The in-school learning resulted in nine clusters of Covid-19 cases involving 13 educators and 32 students at six of the schools.

Eight of the nine clusters involved at least one educator, and an educator was the first identified coronavirus patient in at least four of the clusters. Half the school-associated cases owed to educator-to-student transmission that likely originated from educators first spreading the virus amongst themselves, including “during in-person meetings or lunches,” the study found.

“Initial infections among educators played a substantial role in in-school transmission and subsequent chains of infection to other educators, students, and households, highlighting the important of preventing infections among educators in particular,” the study authors wrote.

All nine clusters “involved less than ideal physical distancing” and five involved “inadequate mask use by students,” according to the study.

The study authors said vaccinating teachers, when vaccine is available, might be helpful.

Expert: We need to be vaccinating our teachers

While teacher vaccinations are important, they’re not vital to reopening schools, Walensky told CNN earlier this month.

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

President Joe Biden has previously said he believes teachers should move up in vaccine priority, but White House officials have stressed they do not believe teachers must be vaccinated for schools to reopen safely.

“Even though we don’t feel that every teacher needs to be vaccinated before you can open a school, that doesn’t take away from the fact that we strongly support the vaccination of teachers,” Dr. Anthony Fauci said during a White House briefing last week.

Meanwhile, at least one leading expert continues to stress she believes teacher vaccinations are “essential” to paving a way back to class.

“The CDC and the Biden administration need to step up right now and say that teacher vaccinations are essential,” Dr. Leana Wen, emergency physician and visiting professor at George Washington University Milken Institute School of Public Health, told CNN on Monday. “If getting our children back in school, in person, is really a priority, we need to be vaccinating our teachers.”

So far, at least 28 states and Washington, DC, have started allowing all or some teachers and school staff to receive Covid-19 vaccines.

Pushing to reopen schools, from New York to LA

The national conversation about prioritizing teachers to get vaccines continues to simmer as more local and state leaders announce plans for reopening schools.

In California, the Los Angeles Unified School District — the nation’s second largest school system — aims to welcome back preschool and elementary students for in-person instruction no later than April 9, Superintendent Austin Beutner said Monday.

“As difficult as the decision was to close school classrooms, reopening is even harder,” Beutner said. “We cannot — and will not — compromise on health and safety.”

That decision was guided by Los Angeles County health officials’ announcement last week that Covid-19 case levels were low enough for elementary schools to reopen, the superintendent said. But a union representing more than 30,000 teachers in Los Angeles says schools should remain closed because children and educators will be put at risk without proper health and safety precautions.

“It is unfortunate that educators are being targeted, and the pressure of preventing an unsafe return falls to us while our students and their families face economic devastation, illness and death,” UTLA President Cecily Myart-Cruz said in a statement to CNN.

Los Angeles County health officials have said that beginning March 1, educators and child care workers in the county will be eligible to receive the vaccine. And last week, Gov. Gavin Newsom said the state will set aside 10% of Covid-19 vaccine doses to be used to teachers and child care workers in efforts to help resume in-person instruction.

New York Gov. Andrew Cuomo has also pushed for local governments to work on getting schools open “unless there’s a community or school that has an infection spike.”

“Students deserve in-class teaching,” he said last week. “Vaccinate the teachers.”

On Monday, Cuomo said he has asked all local districts to report by this week how many teachers have been vaccinated.

“Teachers are very concerned that before they return to the classroom, they are vaccinated,” he said. “I think we need clarity on that matter, opening schools is very important, very important for children.”

Meanwhile Kansas Gov. Laura Kelly announced a back-to-school vaccine plan last week, saying the state was now receiving substantially more Covid-19 vaccine doses and under the plan counties would receive additional vaccine shipments explicitly earmarked for K-12 teachers and staff.

In addition to the teacher and staff vaccinations, the state would provide free rapid results testing supplies to schools.

“The emphasis on vaccinating K-12 teachers and staff, the free testing supplies, along with continued adherence to other mitigation strategies will allow us to bring students safely back to in-person learning,” the governor said.

The-CNN-Wire

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