Testing Shows Schools Aren’t Propelling Covid-19 Outbreaks
(Bloomberg) -- Schools across the U.S. have been open for weeks, and so far relatively few appear to have spread Covid-19 among students or into wider communities. Now, with holiday travel ahead and infections surging, teachers and parents are waiting to see whether that success holds.
In New York City, the first major U.S. city to fully reopen its public schools, random testing of students and staff in its most recent sampling two weeks ago, showed an extremely low positivity rate of less than 0.2%. Even as cases have spiked in some areas of Brooklyn and Queens, causing schools there to shutter, no outbreaks in schools have been reported.
But the story is very different elsewhere. Michigan, where cases are surging, has reported more than 90 outbreaks of the virus at pre-kindergarten through high school classes. Of those, 29 were reported just last week.
“You can’t really pull the school out from the community,” said Walter Gilliam, an education policy researcher at the Yale School of Medicine. “The biggest part of this, really, is how do you keep transmission rates in a county to a level that the schools even have a chance? If the transmission rates are too high, there's just almost nothing they could do to keep it from getting into schools.”
What these two extremes show is that school children probably are not major spreaders of Covid-19 among each other, their families and the wider community, as had been initially feared. Instead, they are more likely accurate reflections of conditions in the broader community. A recent large-scale study co-authored by Gilliam showed that child-care programs that remained open throughout the pandemic did not appear to contribute to the spread of the virus among child-care providers.
Other early evidence similarly suggested that schools don’t inherently become virus hot spots. Insights for Education, an independent foundation that advises education departments and ministries, examined data from 191 countries between Feb. 10 and Sept. 29 and found “no consistent pattern between school status and infection levels.”
In Spain, a second wave of the virus began before schools reopened. One analysis there found that in one region cases dropped three weeks after schools reopened, in one region cases stayed flat and in others case numbers continued rising at the same rate. A new project that is collecting data on reopenings in the U.S., the COVID-19 School Response Dashboard, examined data from more than 5,000 schools across all 50 U.S. states and found that at a late-September peak, about 3% of schools reported outbreaks of five or more infections.
Some, including White House Covid-19 advisor Scott Atlas, have touted such evidence as justification for a full-force return to in-person learning. Atlas recently tweeted coverage of the Yale study. But Gilliam quickly responded via tweet that Atlas had misinterpreted its findings. “You clearly need to read the science before tweeting it,” he wrote. “I should know — I’m the study’s lead author.”
Gilliam and others caution against reading too much into his and other studies. His own work, he pointed out, studies child-care settings, where groups of children are far smaller than a typical pre-k or kindergarten class, and where caregivers were perhaps better equipped to put in place extensive health and safety measures.
Some early evidence suggests that children over 10 may be more likely to catch and spread the virus. Those risks also increase as older kids move from classroom to classroom, attend larger classes and expand their circles for socializing and mingling.
Insights for Education’s chief executive officer, Randa Grob-Zakhary, said that schools around the globe “did not seem to be the provocateur” of outbreaks and that those that reopen gradually and with practices such as social distancing in place seemed to fare best.
In the U.S., school openings have been complicated and confused by a White House that has downplayed the risks of in-person instruction and federal agencies that have never issued clear guidelines for safe practices. That’s left policy-making to state and local governments that are rushing to respond to the changing virus and what’s learned about it.
Whether it’s safe to open schools, said Rainu Kaushal, a clinical researcher at Cornell University’s medical school, Weill Cornell Medicine, in New York City, depends largely on two factors: How serious the spread of the virus is in the community and how seriously the community is taking precautions against the virus.
She said schools also need to be nimble.
“This virus situation evolves so rapidly that one can only make the best decision for the next few weeks,” she said. “And then you really have to take stock again.”
©2020 Bloomberg L.P.