Widespread use of face masks could help economies reopen safely from coronavirus lockdowns when combined with continued social distancing and other prevention measures, according to a new study.
The risk of transmission is lower in households and among contacts of infected people when masks are worn, according to the study, published in The Lancet medical journal. For medical professionals in a health-care setting, respirator-type devices provide a higher level of protection than standard surgical masks, the report said.
Researchers reviewed data from 172 studies assessing the effectiveness of masks, distancing, eye protection and other measures in preventing transmission from patients with confirmed or probable Covid-19, Middle East respiratory syndrome or severe acute respiratory syndrome, known as SARS.
“Universal face mask use might enable safe lifting of restrictions in communities seeking to resume normal activities and could protect people in crowded public settings and within households,” Raina MacIntyre, professor of global biosecurity at the University of New South Wales in Sydney, said in a linked comment on the study.
The study was funded in part by the World Health Organization and conducted by researchers at more than a dozen universities, hospitals and other institutions in countries including Canada, the U.S., China and the U.K.
Mask use by the general public has divided health authorities, with countries like Austria, Germany and the Czech Republic taking steps to encourage it. Others, like the U.K., have been more circumspect, in part because of concerns about possible shortages for health-care workers. The researchers called for action to ramp up output worldwide.
They cautioned that there is low certainty to the findings on the benefits of masks for the wider public. Social distancing also plays a key role in preventing transmission, with a 1-meter buffer between people significantly reducing the risk, the researchers said. Every meter beyond that, up to 3 meters, was associated with halving the likelihood of passing on the virus.