Most patients who contracted COVID-19 during their stay at a U.K. hospital got it from other patients, not hospital staff, according to a study published Aug. 24 in eLife.
Researchers used viral genome sequence data and clinical information to analyze how COVID-19 spread among patients and staff in five units at Addenbrooke's Hospital in Cambridge between March and June 2020.
Of the 22 patients who contracted COVID-19 during their hospital stay, 20 were infected by other patients, researchers found. In addition, just 21 percent of patients were responsible for 80 percent of infections, a pattern that is consistent with superspreader events, the researchers said.
"The fact that the vast majority of infections were between patients suggests that measures taken by hospital staff to prevent staff transmitting the virus to patients, such as the wearing of masks, were likely to have been effective," lead author Chris Illingworth, PhD, a researcher at the MRC Biostatistics Unit at the University of Cambridge, said in a news release.
The findings also underscore the importance of mask-wearing and regularly screening patients for COVID-19, even if they are asymptomatic, Dr. Illingworth said.