Study: Reopening K-12 schools did not increase hospitalizations when COVID-19 cases were low

Reopening K-12 schools in the United States did not result in an increase in hospitalizations  — in most cases —  due to COVID-19, according to a new study by the National Center for Research on Education Access and Choice (REACH) at Tulane University. 

The study is the first to examine how reopening schools in-person has affected COVID-19 health outcomes.  

Researchers found no evidence that reopening schools in-person or in a hybrid form increased COVID hospitalizations in the 75 percent of counties that had low COVID hospitalization rates during the summer, prior to reopening schools. It seems safe to reopen schools when there are no more than 36 to 44 total new COVID hospitalizations per 100,000 people per week, said study co-author and REACH Director Douglas Harris, an economist of education at Tulane.

“This conclusion is consistent across a wide range of data and research methods. It appears that, when hospitalizations rates are low, it is safe to reopen schools in-person,” Harris said. “This is important given the side effects of closure for students, such as limiting access to essential services, social isolation and learning loss.”

For the counties that had higher rates of hospitalizations in the summer, the study results were inconclusive because the results were inconsistent when the researchers used different data sources and statistical methods.

“However, given the spike in hospitalizations in recent months, policymakers should be cautious. It may not be safe to reopen schools where the virus is already widespread,” said study co-author Engy Ziedan, a health care economist at Tulane. 

Harris also noted that, “It’s not just whether schools reopen but how. If they do reopen, schools need to be vigilant about mask-wearing and social distancing—and so do their communities.” 

The authors also emphasized that keeping teachers and school staff in high-risk categories out of school also remains important.

The researchers used data on essentially all school districts’ reopening plans from Education Week and two private data collection companies, Burbio and MCH Strategic Data. They combined these with information on COVID-related hospitalizations from the company Change Healthcare, which has healthcare claims for 170 million people, roughly half of the entire U.S. population, as well as data from the U.S. Department of Health and Human Services (HHS) including essentially all U.S. hospitals. The authors examined data for every county from Jan. 1 through Oct. 30, 2020. 

This is a significant advance over prior studies that have focused on schools and the COVID-19 positivity rates. 

“COVID testing is too infrequent and unsystematic to be informative about the effects of school re-openings on the virus's spread, said study co-author Susan Hassig, a Tulane epidemiologist. “The hospitalization data, in contrast, does not have these problems, and focuses on what matters most—whether people get sick.”

The full study is available at