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‘Swiss cheese model’ of precautions allows schools to open safely despite coronavirus, experts say

Rewind one year: Fresh finger-paintings dry inside silent classrooms. Half-read books gather dust on shelves. The plant on the teacher’s desk is starting to wilt, but still alive.

If we knew then what we know now, schools wouldn’t have closed because of the COVID-19 pandemic — or at least, not for very long, said George Rutherford, professor of epidemiology and biostatistics at UC San Francisco.

“We were working on the playbook for Influenza A — the first things to close are elementary schools because children are huge amplifiers,” Rutherford said. “But that’s just not the case here.”

As many of California’s sleeping giant school districts lumber toward April campus reopenings — after more than a year in the suspended animation of distance learning — some parents and teachers have that queasy feeling in the pit of their stomachs. They worry about safety, despite myriad studies showing that open schools don’t result in significant spread of COVID-19.

To wit: Only about 35% of elementary schoolchildren in the Los Angeles Unified School District are expected to return to campus, along with just 22% of middle-schoolers and just 14% of high-schoolers, according to its latest parent survey. This, even as dozens of schools in nearby Orange County have been open since September.

Santa Ana residents Sara Greene and her husband have been vaccinated, but she’s concerned about her 6-year-old. “I was thinking that we should send him back, but recent news about the variants has me second-guessing,” Greene said.

U.S. Centers for Disease Control

Should she worry? Experts turn to data. According to the U.S. Centers for Disease Control: Seniors older than 85 are 7,900 times more likely to die from COVID-19 than are school-age kids (5 to 17). Adults 50 to 64 are 400 times more likely to die than school kids.

“It’s possible to open schools safely — it’s being done,” said Grace Lee, professor of pediatrics at Stanford University School of Medicine and chief medical officer for practice innovation and infectious diseases physician at Stanford Children’s Health. “It all goes back to the Swiss cheese model.”

For the uninitiated, the Swiss cheese model involves overlapping layers of protection — proper masking, sanitation, physical distancing, air filtration, keeping social “bubbles” as small as possible, ensuring children don’t show up at school when they’re sick. Lee likens it to Swiss cheese because there are holes in any one of the layers, but piled atop one another, none of those holes show through.

“Me and my family — we’re eagerly embracing having our kids be in school, and we’re also maintaining our other strategies,” said Lee, who has children in middle school and high school. “We keep our bubbles tight. No big trips planned. We wear masks and keep our distance — and I’m vaccinated!”

Might more virulent virus variants break through the layers of protection? Variants are a concern in the big picture, but schools haven’t proven to be big viral incubators as long as precautions are taken, she said.

“I would argue that adults in general have been responsible for more of the transmission than are kids,” she said. “Adults in educational settings have been vaccinated, mitigating transmission there. And everyone will still be taking precautions like masks and distancing. We worry the most when those mitigation measures are not in place.”

Third-grade student Austin Lee wears his astronaut helmet he made in class at Red Hill Lutheran School in Tustin, CA on Wednesday, February 10, 2021. Students got to ask questions of astronaut Mike Hopkins, who is aboard the International Space Station, during an 11 minute window as the ISS passed over California. (Photo by Paul Bersebach, Orange County Register/SCNG)

Closed anyway

Some districts will not welcome children back to campus despite a robust body of evidence showing that schools have safely reopened in the U.S. and many other parts of the world, and despite the lure of $2 billion in extra funding the state is dangling to persuade local districts — which hold the decision-making power here — to throw open their doors.

With case counts and hospitalizations plummeting in California since January, and with teachers and school workers getting vaccinated, the continuation of distance learning isn’t so much about COVID-19 fears as about asking kids to adapt to yet another disruption with only one quarter left to the school year.

The San Bernardino City Unified School District, the state’s sixth largest with 57,000 students, is one of them.

“In spite of the ever-changing shifts in guidance, our Board of Education has not wavered from the decision they made back in November” to remain closed through the end of this school year, said spokeswoman Ginger Ontiveros. “Our commitment to distance learning was originally based on the exceptionally high COVID-19 rates in the community we serve, and now it provides an important level of instructional consistency for students, teachers, and families as we approach the end of this school year.”

California is one of the slowest states in the nation to reopen schools, according to federal data. All schools in Florida offer in-person learning. In Connecticut, 62% of schools do. In California, only 18% do.

The majority of middle and high schools, and a significant number of elementary schools, remain closed to in-person classes, according to state data. And some frustrated parents point out that “reopening” isn’t as grand as it sounds: A great many of the schools welcoming kids back to campus will only host classes for a few hours a day, or for a few days a week.

“It’s a constitutional right for students in K-12 to get in-person instruction at school,” said Ginny Merrifield, executive director of the Parent Association, which is pushing to reopen schools in California. “You can’t negotiate that away.”

The California Teachers Association, meanwhile, polled registered voters and found that most think safety — not speed — should guide reopenings.

But the two don’t have to be mutually exclusive.

Students at San Fernando Elementary Zoom with their teacher Stephanie Levinson in the wake of coronavirus school closures. (Courtesy of LAUSD families and Stephanie Levinson)

Why most kids don’t get sick

Scientists aren’t completely sure why children usually escape severe illness when they get COVID-19 — Rutherford jokes it might be because they’re short — but they have some good ideas.

“One of the things we know about the COVID-19 virus is that it has a receptor that allows it to get into our airways,” said Sandra R. Hernández, president and CEO of the California Health Care Foundation, on a panel for the Public Policy Institute of California. “Kids under 12 just have many fewer of these receptors.”

Rutherford said these receptors sort of “bloom” after age 10 — or, more precisely, the gene for the receptors is expressed — and by the time children turn 18, they’ve reached adult levels. That fits the observation that cases are more common among high school students.

Transmission in schools appears to be primarily from teacher to teacher, then from teacher to student, but almost never from student to teacher, Rutherford said.

That has been Marin County’s experience. Schools there partially reopened in September and celebrated 1 million combined “student-days” of in-classroom instruction last month. There were only 10 cases of suspected in-school transmission of COVID-19 as of early February. Of those 10, half were student-to-student, three were adult-to-adult and two were adult-to-student. There have been no student-to-adult transmissions in school, the county health department said.

Newport Mesa Unified School District, which has been holding in-person classes this year, has 10 current cases among more than 17,000 staff and students.

Fifth graders study math at Westmont Visual and Performing Arts Academy in Westminster, CA, on Friday, March 26, 2021. Elementary school students in the Ocean View School District will be transitioning back to five days a week on-campus instruction starting Monday, March 29.(Photo by Jeff Gritchen, Orange County Register/SCNG)

Among 25,000 staff and students in the Irvine Unified School District, just nine COVID-19 cases were confirmed this week, according to district data. Most of Irvine’s students returned for in-person instruction in September, with only about one-third studying exclusively online, said Therese Sorey, president of the Irvine Teachers Association. Not everyone is fully vaccinated yet, but things are humming along.

“The teachers are struggling less to get their appointment for vaccines, but most of them have managed to have at least one so far,” she said. “The district will make no further changes to this school year’s schedules or safety procedures, but they are following guidelines for some sports activities and trying to trying to arrange safe promotion and graduation ceremonies.”

Learning setbacks

Research has found that the pandemic has set back learning for all students, but especially for students of color.

Assessment data from the fall showed that, on average, kids started this school year about three months behind where they were expected to be in math. Students of color were three to five months behind, while White students one to three months behind.

In reading, they were about 1 1/2 months behind.

Stress, depression and anxiety levels are up.

“Black and Hispanic students continue to be more likely to remain remote and are less likely to have access to the prerequisites of learning — devices, internet access, and live contact with teachers,” said a study by the global management consulting firm McKinsey & Co.

“Left unaddressed, these opportunity gaps will translate into wider achievement gaps. … (C)umulative learning loss could be substantial, especially in mathematics — with students on average likely to lose five to nine months of learning by the end of this school year. Students of color could be six to 12 months behind, compared with four to eight months for White students.

“While all students are suffering, those who came into the pandemic with the fewest academic opportunities are on track to exit with the greatest learning loss.”

The state plans to spend $4.6 billion to tackle these issues, funding summer sessions, tutoring and mental health services to “empower schools to develop and execute comprehensive strategies to both reopen and expand programs to address the social-emotional, mental health and academic needs of students,” according to the governor’s office.

The catch-up will look different from district to district, and plans are still jelling. “We are currently preparing for a robust summer program and adding accelerated learning supports to help students get ready for a strong start to the 2021-2022 school year,” said Ontiveros of San Bernardino city schools.

If local COVID 19 rates allow, it plans to offer in-person summer school that’s “both more intensive and more universally available,” she said. “We are making plans to accommodate every student and not just those who need credit recovery.”

The districts plans to provide one-to-one tutoring supports at all grades and specialized interventions to support early literacy and elementary school math. The initiatives will continue through the entire next school year, officials say.

Lee, of Stanford, doesn’t downplay COVID-19 among kids. But she believes the Swiss cheese model, practiced well, has proved protective. “The more layers you put in, the better,” she said. “The greater risk is that people get overconfident, expand social bubbles too quickly and drop protective measures at the same time.”


Source: Orange County Register

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