Is there evidence of in-class transmission of SARS-CoV-2 on a university campus that has mandated vaccination and masking? The answer is no.
“Going back to full-occupancy, in-person teaching at Boston University (BU) did not lead to SARS-CoV-2 transmission in-class,” said corresponding author John Connor, PhD, associate professor of microbiology at Boston University School of Medicine (BUSM).
SARS-CoV-2, the causative agent of COVID-19, has displayed person-to-person transmission in a variety of indoor situations. This potential for robust transmission has posed significant challenges to day-to day activities of colleges and universities, where indoor learning is a focus, with concerns of transmission in the classroom setting affecting students, faculty and staff alike. Understanding whether in-class instruction without any physical distancing is fueling transmission is an important question that has not been adequately addressed.
To determine whether in-class instruction without any physical distancing, but with other public health mitigation strategies (masking, surveillance testing, enhanced air filtration, vaccinations), is a risk for driving transmissions, researchers from BUSM used a blend of surveillance testing, epidemiology and viral genomic to analyze the incidence of likely transmission of more than 140,000 class meetings.
For each potential in-class transmission event, the researchers analyzed the SARS-CoV-2 genome to understand whether there really was classroom transmission. “Our reasoning was that if there was in-class transmission, then each person in that potential transmission event would have the same genome,” said Connor. “If there was not in-class transmission then the two people would have genomes that are genetically different. It turned out that none of the nine potential in-class transmission events was real.”
These findings appear online in the journal JAMA Network Open.