COVID and Schools: The Data and Science Then and Now

Early on in the pandemic the thinking was that masks were not necessary. In fact, there is a video circulating online that shows Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health (NIH), saying “there’s no reason to be walking around with a mask.” Fauci’s remarks were made on March 8, 2020 and do not represent his current stance or the national conversation about the importance of face coverings nor the updated guidance issued by the Centers for Disease Control and Prevention (CDC). That was then, this is now.

In early November, a staff writer for the American Association of Medical Colleges (AAMC) argued that “An emerging body of evidence suggests that young children do not spread the coronavirus easily. Does that mean it’s safe to bring them back to class?” Here were the core arguments of the piece:

  • The virus spreads in schools — but schools are rarely superspreaders
  • School outbreaks typically come from the community — not vice versa
  • Children transmit the virus — but not how adults do

For months, the common conversation in the media and research was that schools were not heavily documented sites for Covid or superspreading events. But I kept hearing anecdotally from the field that the situation was different. A friend that works in a Texas school district was infected in a public school by another teacher. The friend relayed that the teachers were rapidly getting sick in her school, but the students were not showing symptoms. This is not the only Texas superspreader event that flew under the radar. The Texas State Board of Education hosted their own superspreader event when they were forced to meet in person by Board leadership to make a political point. The argument made was if the State Board of Education couldn’t meet in person, why would school districts across the state of Texas agree to do so? While I am not an epidemiologist, anecdotally, this information seems quite problematic compared to the public discourse about school reopening. The AAMC article did include an important caveat and/or hedging.

The early data suggest that schools can reopen safely under certain conditions, but the analyses come with follow-up questions and multiple caveats — the most basic of which is some form of, “That’s what we know so far.” “We’re nine to 10 months into a brand-new disease,” cautions Helen Bristow, MPH, program manager of Duke’s ABC Science Collaborative, which guides schools on COVID-19 safety. “We’re regularly learning something we didn’t know before.”

That was then and this is now.

So what is the latest? The Guardian reported on January 2, 2021 that Symptomless cases in schools could be key driver in spread of Covid-19. Please read that again. They report that Up to 70% of schoolchildren infected with coronavirus may not know they have it until after a positive test result.” Please read that again. In my own experience, I have heard many stories of people testing negative and then not soon after testing positive and/or having symptoms. Has this “negative” test situation happened to your friends and family too? This is now being borne out in the broader data.

A key factor in the spread of Covid-19 in schools is symptomless cases. Most scientists believe that between 30% and 40% of adults do not display any Covid symptoms on the day of testing, even if they have been infected. For children, however, this figure is higher. “It is probably more like 50% for those in secondary school while for boys and girls in primary school, around 70% may not be displaying symptoms even though they have picked up the virus,” says Professor Martin Hibberd of the London School of Hygiene and Tropical Medicine.

The Guardian

We don’t know what we don’t know. Proponents of immediate school reopening often point to contact tracing and testing. However, in the United States the number of cases has rapidly overwhelmed contact tracing and testing. It’s hard to argue that testing and contact tracing is currently adequate for K-12 schools.

The US Department of Education has absolutely failed in its responsibility to track the spread of Covid in higher education and K-12. LITERALLY FAILED. Besty DeVos said it was not her job. In the absence of leadership from Betsy DeVos and the US Department of Education, the free press of our nation have stepped into that glaring gap. The COVID Monitor is a US News database that tracks coronavirus cases in K-12 schools. They’ve shown there had been nearly 250,000 student and staff cases across the United States since Aug. 1— and that data doesn’t include the massive December surge. Read that again. 250,000. While those have been tied to schools, we also know that more than 1 million children have been diagnosed with COVID-19 in the United States.

The most distressing part of this pandemic is the death. Every time I have been forwarded an article by a reader of Cloaking Inequity about the death of an educator, I have posted it on my Twitter to make point. Educators are being infected with Covid and they are dying.

Inaccurateunproven claims have filled the data gap, aiming to assuage anxieties about reopening schools for in-person classes, with seemingly little regard for the potential impacts the virus may have on the students, staff and communities affected by such choices. With uncertainties about the long-term effects of infection on an individual’s health, the evidence of children being asymptomatic spreaders and the increase in pediatric cases recently, public pleas for closing schools have grown.

In guidance from the Centers for Disease Control and Prevention, schools are called a “potential source of COVID-19 outbreaks, due to the number of individuals intermingling in close proximity for extended periods of time.”

It makes sense when you think about it. Stuff a bunch of people into a confined space for eight hours a day and the likelihood of catching the virus increases

And internationally, data indicates how quickly schools may become superspreaders.

In Israel, for example, many schools closed due to COVID-19 outbreaks only two weeks after the country fully reopened classrooms. Districts in Georgia and Mississippi experienced similar scenarios when they started school in August. 

recent study from the United Kingdom in November also showed a decline in cases in every age group except, apparently, among school-aged children and teens.

US News

Yes, internationally, they have already figured out in the public consciousness that schools are platforms for superspreading. It is very clear that Covid has taken advantage of some of American’s most challenging traits— denial and hubris— in the debate about reopening schools.

So what does the national data reported in early December by US News tell us about the situation with communities, schools, and Covid?

  • Their analysis of their national data shows that the high school student case rate (13 per 1,000 students enrolled for in-person classes) is nearly three times that of elementary school students (4.4 per 1,000). 
  • They observed that the higher the community case rate, the higher the school district case rate, as depicted in the graphic below.
  • They found that case rates for school districts are often much higher than case rates in the community. Meanwhile, within their data, a recent review of school district case rates based on total enrollment showed that less than 3% of all districts reporting two or more cases met a lowest-risk, case-rate threshold advised by the CDC for communities.
  • They also show that the percentage of students enrolled for in-person classes directly impacts the case rate in school districts. A recent study based on their data found school districts can reduce COVID-19 case rates by about 40% by reducing the in-person class size by 50%.
  • Based on data from Florida, their data show that school districts without mask mandates have an average case rate (12.1 per 1,000) nearly twice as high as those with mask mandates (6.9 per 1,000).

Do you come away from this independent national data thinking that schools are safe to reopen under current circumstances and do not contribute to the spread of the virus?

Also, there is worrisome new data. @DrEricDing wrote that the “new B117 Covid variant is not only more infectious, it’s potentially more infectious in children 0-9 (+24%) and 10-19 (+14%), and less among 60-79, compared to common strains. More sobering—the R estimate is much higher.” See more at this thread h/t to LH.

Arguments about social and mental well-being of students due to online learning have been made by experts in various fields. However, now that we have data, research and experience strongly indicate we need to prioritize the health of communities in the midst of a worldwide pandemic. We must do this until ALL states prioritize the vaccination of educators and provide the financial and strategic resources to reopen safely. States should immediately prioritize this goal so that we can both address the social and mental well-being of students as well as protect the health of the nation.

We’ve seen how problematic and absent leadership has led to less than a quarter of Covid vaccines (as of right now) being used for vaccinations in Florida, Texas and other states. Yet many states are insisting and placing enormous political and financial pressure on schools to reopen. It’s a severe and gross failure of leadership to allow vaccines to sit on shelves and at the same time demand educators reopen schools. I have been impressed by the leadership in Kentucky prioritizing educators for inoculation as a high priority group so that schools can reopen more safely. Furthermore, absent inoculating all educators and providing the financial and strategic resources for districts to reopen schools safely (i.e. PPE, smaller class sizes etc.) for students and families, President-elect Joe Biden’s promise to open all schools in the first 100 days is a problem and a national disaster waiting to happen. I am sure President-Elect Joe Biden is aware that Secretary of Education-Designate Cardona pressured schools to reopen in Connecticut throughout 2019. So, considering the current knowledge in the data and science, it is my hope that Biden and Cardona get it right on school reopening in the upcoming months, otherwise history and voters won’t be kind.

Please Facebook Like, Tweet, etc below and/or reblog to share this discussion with others.

Check out and follow my YouTube channel here.

Twitter: @ProfessorJVH

Click here for Vitae.


  • Pingback: The Teacher Trauma of Repeatedly Justifying Your Right To Life During Covid | gadflyonthewallblog

  • Emily Oster (and her coauthors) have some of the best if not the best data-driven analysis on this topic:

    I suggest EVERYONE take a look at her work.

    Anecdotal evidence is NOT evidence…That is not how the scientific method works…


  • Pingback: 2021 Medley #1: Bye, Bye Betsy and other stories | Live Long and Prosper

  • Pingback: Why Are Schools Opening When Covid-19 is Surging?

  • Covid is on rise. Vaccines are out. Leadership at my school district is so far behind the 8-ball. While we should be getting and scheduling VACCINES, we get an email today from our leader about how they will start rapid resting at schools of SYMPTOMATIC students after the nurses get trained and then they get schools supplied with tests. So in Six months…? I had six reports from students today that they or someone in their family is positive – just today. Businesses, parents, counties, governments, and district leaders need to think what your behaviors say….to teachers. We know you don’t care. (It goes without saying, students aren’t the problem and we love our students.).


  • Thank you for writing this column. In the past two weeks, two doctors have “explained” to me, unsolicited and in the course of unrelated office visits, that I am in no danger of contracting COVID-19 by teaching in a high school. One actually told me that teenagers “do not get COVID.” Every morning I open the paper and read about how schools are clearly not spreading the virus, and that reopening has been a spectacular bright spot in an otherwise grim season of misery and selfishness. Hold on just a minute! I am unconvinced that the custodians who clean the doorknobs once an hour–while well-intentioned– are keeping anyone safe. A 28-year-old teacher was hospitalized with COVID-related pneumonia last week and no contact tracing was done. We are told that all cases are being transmitted outside of school (like when the students go out for pizza at lunch?) The administration’s coordination with the health department is shrouded in secrecy (maybe ineptitude), although the press did pick up the story about our superintendent threatening to “cough all over everyone” at his health club if they didn’t suspend his membership charge. Sadly, the politicization that has hijacked reason extends to our faculty. Anecdotally, the students appear to be taking the mask and social-distancing guidelines much more seriously than the teachers who mutter incomprehensible “OAN insider phrases” about the fraudulent election to each other. In the faculty room (I am told) teachers are free to eat and socialize maskless–the length of a period is 47 minutes.


  • Dr. Karen Bridges

    Thank you Dr.Heilig for presenting and informing us on this issue from a logical standpoint. I am a school administrator. My office manager and I were commenting on the high rate absences due to the flu in our school from early January to late February 2020. We both acknowledged that it was strange for so many students to be out sick with the flu. We had a lot of teacher absences in those first two months of 2020 due to flu like illness. And no, we are not truly certain that students present infection in the same manner as adults. But, we do know that since schools were cancelled early on in the pandemic that the exact rate at which students could infect adults is not clearly known. However, it would be a good study to examine study absenteeism rates 2 to 3 months prior to schools shutting down. And look at those absences to see how many were due to illnesses with symptoms similar to COVID. Then perhaps we can start to see if there a pattern, if it could be related to COVID.


Leave a Reply

Please log in using one of these methods to post your comment: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s