Vaccinated and masked college students had virtually no chance of catching COVID-19 in the classroom last fall, according to a sweeping study of 33,000 Boston University students that bolsters standard prevention measures.
The researchers screened the college’s health records to find nine sets of students who developed COVID-19 at about the same time, were in class together without social distancing and had no known contact outside school, suggesting that they might have transmitted it in the classroom. However, genome analysis of coronavirus samples from the groups showed that all of them more likely were infected in other places.
“When we looked at the genomes and compared them to one another, they were cousins but not closer than that,” said Boston University School of Medicine virologist John Connor, a co-author. He said the study in the journal JAMA Network Open provides an answer to a nervous question common last fall: “I just walked into a class with 80 people in it. How do I know I’m not going to catch disease from them?”
