Data suggests schools aren't superspreaders

As the number of active coronavirus cases in Lincoln County ebbs and flows, Libby Superintendent Ron Goodman is seeking to dispel what he sees as a misconception of how the virus has spread locally.

While the repeated suspension of in-person learning at the Libby Elementary School and Libby Middle High School amid the pandemic may give the impression that the district is responsible for a high number of cases, Goodman argued that data gathered by the district suggests otherwise.

Since schools reopened this fall, 412 students and staff have had to quarantine after coming in close contact with infected individuals at the school. A total of 44 students and school employees have tested positive for the virus. Health department officials suspect that only eight of those who were infected with the virus — or roughly 18 percent — contracted it while at school.

“Out of all these opportunities [for infection], that’s not all that bad,” said Goodman.

Administrators have twice put a hold on in-person learning at both the elementary and middle high school this year. While the spread of the virus between staff members at the elementary school partially led to one of the closures, Goodman said in both instances he had to close school buildings after realizing the district did not have the numbers to keep them open. He anticipated that too many employees would be in quarantine after health department officials completed contact tracing.

It is important to note that being quarantined does not necessarily mean a person has tested positive for the virus. It only means they have come in close contact with someone who has.

Jennifer McCully, county public health manager, said while health department officials have recorded cases of the virus being transmitted within schools, overall the spread has been minimal.

“So far it's been pretty good,” she said on Nov. 25.

Goodman’s local assessment largely echoes claims made by researchers studying the spread of the virus on an international scale. According to the science journal Nature, outbreaks in schools are uncommon across the globe even in places where community infections were on the rise.

Of the more than 65,000 schools that reopened in Italy in September, only 1,212 experienced outbreaks four weeks later despite rising case numbers. In 93 percent of these cases, only one infection was reported. Only one of the high school included in the study had a cluster of more than 10 people.

Nature reported a similar outcome when a second wave of coronavirus infections hit the state of Victoria, Australia in July. While acknowledging that schools and childcare centers were only partially open at the time, researchers found little evidence to suggest they served as superspreader sites.

After collecting data from 191 countries, Insights for Education, a non-profit that advises educators around the world, reported that no consistent pattern emerged between school status and coronavirus infection rates.

The foundation’s report, which was not peer-reviewed, tracked data from February through September. Some countries such as Croatia, saw the number of coronavirus cases rise during summer break then drop after schools reopened. Others, such as the United Kingdom, saw relatively low case counts during the vacation period and a rise after students returned to classes. In Spain, case counts of the virus rose during the summer and continued rising after schools reopened. In Thailand, a stable infection seen during a vacation period did not change significantly when schools reopened classrooms.

As of yet, the federal government has not organized a systematic effort to track school openings and COVID outbreaks. Some states, such as Utah, have gathered data on school-associated cases within each district. While the spread of the virus was relatively high throughout the state in late October, State Superintendent of Public Instruction Sydnee Dickerson told NPR she believed for the most part schools were not driving the spread.

While acknowledging that health officials have not identified a “massive superspreader event” in U.S. schools, Dr. Wendy Armstrong, Professor of Medicine in the Division of Infectious Diseases at Emory University argued for the need for a more organized surveillance system to gather data.

“Without really broad national surveillance that incorporates all schools and all school systems, with appropriate tracking in those schools, and that is lacking in a lot of places we can’t know for sure [if schools are superspreader centers],” Armstrong said during an October of the Infectious Disease Society of America.

After analyzing survey data gathered from schools across the U.S., Emily Oster, a professor at Brown University, has found that coronavirus infection rates in schools tend to roughly mirror the prevalence of the virus in the surrounding community.

In elementary and middle schools, Oster found rates of the virus are even lower than overall population case rates. This data reflects findings that younger children generally have lower rates of COVID-19.

While representing a smaller sample set than that analyzed by Oster, the data gathered by Libby Public Schools shows that students generally have lower rates of infection than school employees. Despite making up only 15 percent of the district population, adult staff represents 19 out of the 44 total cases — or 43 percent — recorded by Libby schools.

In a Nov. 20 opinion published in the Washington Post, Oster argued that while the data does not mean it’s safe to open schools in all environments, it shows that “by far the most helpful thing we can do for schools is to control community spread.” By the same token, she claimed that when trying to stop the community spread of the virus, shutting down schools is not effective.

Some researchers have criticized Oster’s data, which is crowdsourced and requires schools to self-report information. Melinda Buntin, chair of the Department of Health Policy at Vanderbilt School Medicine told NPR that the data is likely biased towards schools that are organized enough to keep track of their results and are doing an outstanding job of following safety measures.

Buntin, however, has argued in favor of reopening schools so long as school administrators follow precautions designed to limit the spread of the virus. The protective measures she has outlined, such as requiring masks for all staff and isolating groups of students in cohorts, are largely in use at Libby Public Schools.

In an article published on JAMA Network Open, an open-access medical journal, Buntin noted that health experts with the American Academy of Pediatrics, the National Academies of Sciences, Engineering and Medicine and the Centers for Disease Control and Prevention, have made the case for providing in-person education amid the coronavirus pandemic. Public health officials have said school closures are accompanied by the risk that children may experience worsened mental health, lower academic gains, less attention from protective services and reduced access to nutritious foods. For underserved communities, these risks are often more severe.

Keeping children out of classrooms also makes it increasingly difficult for educators to interact with their students. Staying in contact with students over video conferencing software, email Google Classroom and other virtual platforms is often a poor substitute for in-person instruction.

“The subtle nuances you get working directly with kids, you don’t get that over email,” said Wally Winslow, a teacher at Libby Middle High School.

According to the latest guidelines on opening schools issued by the CDC, school administrators should work with local and state health officials and make decisions based on available data regarding levels of community transmission and their capacity to protect students and staff.