Expert Commentary

Teachers and school staff play a central role in COVID-19 outbreaks on campus, research suggests

School employees have been the source of many outbreaks and may be more likely to transmit the virus to coworkers than students, research suggests. Meanwhile, many teachers are at risk for severe illness if infected.

(Hatice EROL from Pixabay)

Even as studies confirm the central role teachers and other school employees play in transmitting COVID-19, government officials across the U.S. continue to disagree whether adults who work with children should wear masks and get vaccinated.

Public health officials have stressed the importance of both in limiting the spread of the coronavirus, especially since the highly contagious Delta variant emerged months ago.

Children under age 12 cannot yet receive the COVID-19 vaccine. Fewer than one-third of U.S. adolescents aged 12 to 17 years were fully vaccinated as of July 31, data from the U.S. Centers for Disease Control and Prevention show.

Meanwhile, child hospitalizations linked to the virus have risen sharply in the U.S. in recent weeks. A Sept. 9 report from the CDC notes that while the weekly rate of hospitalization remains relatively low for kids, it was nearly five times as high in August as it had been in June.

The weekly hospitalization rate among the youngest children — those 4 years old and under –grew almost 10-fold over that period.

In August, as students in some states began returning to campus for the fall semester, the White House’s chief medical advisor, Dr. Anthony Fauci, urged people who work around children to get their shots. He supports mandatory vaccines for schoolteachers.

“We are in a major surge now as we’re going into the fall, into the school season. This is very serious business,” said Fauci, director of the National Institute of Allergy and Infectious Diseases, in an interview with MSNBC.

It’s unclear how many teachers, administrators, classroom aides, athletic coaches, cafeteria workers, crossing guards, bus drivers and other school personnel are vaccinated. If individual states track school employees’ vaccination status, they do not report it publicly, according to Johns Hopkins University’s eSchool+ Teacher & School Staff COVID-19 Vaccination Dashboard. The project provides real-time information about state vaccination plans for teachers and other school employees.

Most states and the District of Columbia gave vaccination priority to teachers, school staff and other frontline workers, allowing them to start receiving inoculations in January or February, a state-by-state analysis from CNN shows.

While no known organization tracks COVID-19 infection rates or deaths among school employees, Education Week has created a memorial to honor those who died of COVID-19. As of Sept. 10, the news outlet reports, at least 1,065 active and retired employees lost their lives to the virus in 2021.

Understanding teachers’ role in transmission

A CDC report published Sept. 3 looks at how an unvaccinated teacher who occasionally took her mask off indoors infected nearly half her students as well as some of their parents and siblings. This past May, the teacher, who worked at an elementary school in Marin County, California, noticed being tired and congested, but attributed those symptoms to allergies, researchers write in the report. She occasionally unmasked to read aloud in class.

In the days that followed, the teacher and 12 of her students, most of whom sat at desks close to hers, tested positive for COVID-19. The CDC determined that a total of 22 children and four parents — including three parents the agency deemed to be “fully vaccinated”– eventually were infected during the outbreak.

“The outbreak’s attack rate highlights the Delta variant’s increased transmissibility and potential for rapid spread, especially in unvaccinated populations such as schoolchildren too young for vaccination,” the authors of the report write.

As of Sept. 2, 2021, more than 5 million children had tested positive for COVID-19, representing 15.1% of all COVID-19 cases nationwide, finds a new analysis from the American Academy of Pediatrics and the Children’s Hospital Association.

The report shows a substantial increase in the share of COVID-19 cases involving children from Aug. 26 to Sept. 2, when many U.S. schools reopened for the fall semester. A total of 251,781 U.S. children tested positive, representing 26.8% of all COVID-19 cases reported in the U.S. during that period.

Over the past year and a half, scholars have studied COVID-19 transmission on school campuses in various parts of the globe. Although they conducted some of the research before vaccines became available, their findings remain relevant. Many school system employees are unvaccinated or not fully vaccinated. Even in communities where the vast majority of teachers are fully vaccinated, academic studies can help explain how COVID-19 affects adults who work in schools and the role they have played in spreading the virus.

The evidence suggests:

  • School personnel have been the source of many campus outbreaks.
  • Infected employees may be more likely to transmit the virus to coworkers than to students.
  • A significant proportion of U.S. teachers are at risk of serious illness if they contract COVID-19, largely because of underlying health conditions.

School outbreaks: Who started it? Who’s affected?

When researchers examined 55 coronavirus outbreaks in England schools last year, they learned most started with an infected school employee. More than half of outbreaks occurred in schools serving students aged 4 to 11 years. In all, 154 staff members and 56 children were infected.

“Probable direction of transmission was staff to staff in 26 outbreaks, staff to student in eight outbreaks, student to staff in 16 outbreaks, and student to student in five outbreaks,” the authors write in the paper, published in The Lancet Infectious Diseases in December.

They add that kids mainly acquired the virus at home and most were asymptomatic.

“Reassuringly,” they write, “we found very little transmission between students, which is consistent with emerging literature for young children.”

When researchers investigated outbreaks at six elementary schools in Cobb County, Georgia, they learned that educators “were central to in-school transmission networks.” For that study, published in February 2021 as part of the CDC’s Morbidity and Mortality Weekly Report series, researchers looked at nine clusters of COVID-19 cases involving a combined 13 educators and 32 students from Dec. 1, 2020 to Jan. 22, 2021.

The main takeaway: An educator was the source of transmission in four clusters. A student was the source in one. Researchers could not determine the source of the other four clusters.

A study in South America unearthed similar results. A school employee was behind a campus outbreak that infected 52 people and led to one death in Santiago, Chile in 2020, finds a paper published in July 2021 in the journal Clinical Infectious Diseases.

Most of the people who contracted COVID-19 were adults — 18 school staff members and 27 parents. Seven children tested positive for the virus.

“We hypothesize that adults, mainly through adult-to-adult contact, seem to have been most affected during this outbreak,” the authors write. “Students, in comparison, were most likely to be infected by adults, either their teacher or parent, and parents were most likely infected during parent-teacher meetings.”

COVID-19 poses severe risk to many educators

Regardless of age, people with certain medical conditions are more likely to become severely ill if they get COVID-19. The CDC maintains a list of these conditions, which include diabetes, obesity, cancer and chronic lung diseases such as moderate-to-severe asthma and cystic fibrosis.

Two recent papers indicate a significant proportion of teachers are at risk of serious illness, hospitalization or death if they contract the coronavirus.

A research letter published late last year in the Annals of Internal Medicine concludes that 39.8% of primary, secondary, and special education teachers have risk factors for severe COVID-19 illness. In all, 50.6% have definite or possible risk factors, according to the analysis, based on nationally representative data from the CDC’s 2018 National Health Interview Survey.

The authors find that “0.7% [of teachers] had cancer, 27.9% had a body mass index (BMI) of 30 kg/m2 or greater, 4.2% had a BMI of 40 kg/m2 or greater, and 8.0% had a cardiac condition.”

In the second paper, the Kaiser Family Foundation, a nonprofit organization that researches health issues, estimates that 1 in 4 teachers — 1.5 million nationwide — have a medical condition that puts them at risk for serious illness. That analysis, however, focuses on a broader group of educators.

The authors, who also relied on data from the 2018 National Health Interview Survey, examined information collected from primary, secondary and special education teachers as well as people who reported being another type of teacher or instructor employed in “Education Services Industries.”

School safety protocols vary

Most states allow individual school districts to make their own decisions on how to keep students and employees healthy and safe, including whether mask wearing and COVID-19 vaccination should be required. As a result, safety protocols vary considerably within and across states.

In some parts of the U.S., state leaders have taken strong stances on the issue. For example, Florida Gov. Ron DeSantis issued an executive order in late July prohibiting schools there from requiring masks. New York. Gov. Kathy Hochul, on the other hand, recently ordered a universal mask mandate across K-12 schools there.

On Aug. 30, the U.S. Department of Education began investigating indoor mask bans at schools in five states — Iowa, Oklahoma, South Carolina, Tennessee and Utah — through its Office for Civil Rights, which enforces federal anti-discrimination laws.

The Department of Education announced it will evaluate “whether statewide prohibitions on universal indoor masking discriminate against students with disabilities who are at heightened risk for severe illness from COVID-19 by preventing them from safely accessing in-person education.”

Florida and a few other states are not included in this review because their bans on school mask requirements aren’t being enforced as a result of court orders or other state actions, according to an agency press release. However, on Sept. 10, an appeals court reinstated DeSantis’ ban.

President Joe Biden has spoken out against bans on school mask mandates. In a televised speech announcing his six-part plan to address rising COVID-19 rates Sept. 9, Biden called on state governors to require vaccination for all teachers and school employees. He also said his administration plans to distribute $2 billion worth of rapid COVID-19 tests to schools and other locations “so that every American, no matter their income, can access free and convenient tests.”

At least nine states — Alabama, Arizona, Arkansas, Indiana, Iowa, Montana, Oklahoma, Tennessee and Texas — forbid their school districts from requiring teachers to get shots, according to Education Week, which has been monitoring education policies governing COVID-19 vaccination and testing in U.S. states and territories.

Meanwhile, Oregon, Washington and Puerto Rico require teachers to be immunized against COVID-19. At least seven additional states — California, Connecticut, Hawaii, Illinois, New Jersey New Mexico and New York — and the District of Columbia mandate either inoculation or regular COVID-19 testing, Education Week reports. It also notes information about teacher vaccination requirements was not available for Florida, Louisiana, Mississippi and Vermont.

The news outlet asserts that the U.S. Food and Drug Administration’s recent approval of the Pfizer-BioNTech vaccine for individuals aged 16 years and older “is expected to pave the way for more vaccine mandates, including for teachers.”

Unions boast high vaccination rates among teachers

Two of the country’s largest school employee unions tout high vaccination rates among their members. But those claims provide a misleading picture of the overall situation, reports The 74, a nonprofit news outlet focusing on education in the U.S.

Last month, Randi Weingarten, president of the American Federation of Teachers, issued a statement saying more than 90% of the educators and school staff her union represents had their COVID-19 shots. The American Federation of Teachers represents 1.7 million teachers, classroom aides and other school personnel as well as college faculty, nurses, health care professionals, federal employees and other workers.

But that percentage is based on a March telephone survey of 893 teachers and other school personnel — 13% of whom were included in the 90% tally despite reporting they intended or were scheduled to get vaccinated, The 74 points out. Further, it’s unclear whether the survey’s results apply only to the sample of people who participated or can be used to estimate the percentage of all AFT members who are vaccinated.

Even so, the results provide limited insight into vaccination rates nationally, Mike Antonucci writes for The 74. Antonucci is director of the Education Intelligence Agency, a for-profit research firm focusing on teacher unions.

“There are almost 8 million public education employees in the United States, of whom only about 1.1 million are AFT members,” he writes. “A large plurality of them work in one state — New York. They are not a broad cross-section of the teacher workforce.”

The National Education Association, another large union representing teachers and school staff, announced Sept. 7 that almost 90% of its members had received at least one dose of a COVID-19 vaccine. That number is based on a nationally representative survey of 2,807 education employees conducted online last month, the union states in a press release.

Together, the two unions represent less than half the nation’s K-12 workforce, Antonucci notes. To fill information gaps, news outlets are reporting on vaccination rates among school personnel in their communities.

For instance, The Palm Beach Post reports that at least 47.5% of the 19,436 employees enrolled in the local school district’s health care plan had their shots by late August. The Associated Press reports that, as of Aug. 30, at least 72% of the 75,000 public school teachers in New York City had received at least one dose of a vaccine. All New York City Department of Education employees must provide proof of receiving at least one dose by Sept. 27, a press release from the city announced.

Further reading

SARS-CoV-2 Infection and Transmission in Educational Settings: A Prospective, Cross-sectional Analysis of Infection Clusters and Outbreaks in England
Sharif A Ismail; et al. The Lancet Infectious Diseases, December 2020.

Clusters of SARS-CoV-2 Infection Among Elementary School Educators and Students in One School District — Georgia, December 2020-January 2021
Jeremy A. W. Gold; et al. Morbidity and Mortality Weekly Report, February 2021.

Severe Acute Respiratory Syndrome Coronavirus 2 Antibody Prevalence in Blood in a Large School Community Subject to a Coronavirus Disease 2019 Outbreak: A Cross-sectional Study
Juan Pablo Torres; et al. Clinical Infectious Diseases, July 2021.

Risk for Severe COVID-19 Illness Among Teachers and Adults Living With School-Aged Children
Adam W. Gaffney, David Himmelstein and Steffie Woolhandler. Annals of Internal Medicine, November 2020.

How Many Teachers Are at Risk of Serious Illness If Infected with Coronavirus?
Gary Claxton; et al. Kaiser Family Foundation report, July 2020.

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