Study supports airborne spread of COVID-19 indoors

Findings of a recent study from the University of Georgia support growing evidence for airborne transmission of COVID-19 in enclosed spaces. Researchers were able to link a community outbreak of COVID-19 in China to a source patient who likely spread the virus to fellow bus riders through the bus's air conditioning system. The study, which was published recently in JAMA Internal Medicine, calls into question the prevailing thought on how COVID-19 can spread. Some of the attendees, it turns out, took two buses to the event creating a unique natural experiment for the researchers. Both buses had closed windows and had air conditioning running, said Changwei Li, an associate professor of epidemiology at Tulane University and study co-author - but one bus carried a patient infected with the virus, and the other did not. Of the passengers who later got sick, the majority of them rode on the same bus as the source patient. Even though the two groups later mixed in with the larger crowd at the worship event, the number of new cases attributed to the event were much lower, suggesting that the bus was the major point of transmission. Further, some of the bus passengers who later showed symptoms of COVID-19, the authors found, were not sitting close to the infected passenger. These findings highlight scenarios where COVID-19 could be spread through fine aerosol particles being circulated in an enclosed space, and as the weather turns colder, Shen and Li hope this work will persuade more people to wear face masks in public areas, particularly in indoor spaces.