Face masks limit Covid spread

 
An enormous randomized research involving more than 340,000 people across 600 villages in Bangladesh has found -- some of the strongest real-world evidence yet -- that masks can help slow the spread of Covid-19.

The largest randomized study, conducted by researchers at Yale University, Stanford University, University of California and others, was able to show the effectiveness of masks -- surgical masks in particular -- in preventing coronavirus transmission in a real-world community setting, according to media reports.

Previous studies, albeit smaller, in laboratories and hospitals had shown that masks help prevent the spread of Covid-19. But the new findings demonstrate that efficacy in the real world and on an enormous scale, reports said.

"This is really solid data that combines the control of a lab study with real-life actions of people in the world to see if we can get people to wear masks, and if the masks work," Laura Kwong, one of the co-authors of the study and an assistant professor of environmental health sciences at the University of California, Berkeley, told NBC.

"I think this should basically end any scientific debate about whether masks can be effective in combating Covid at the population level," Jason Abaluck, an economist at Yale who helped lead the study, said in an interview, reports The Washington Post. He called it "a nail in the coffin" of the arguments against masks. The preprint study was released online on Wednesday by non-profit organization Innovations for Poverty Action and is currently undergoing peer review. The research was led by Kwong, Yale economists Ahmed Mushfiq Mobarak of Bangladesh and Abaluck, and Steve Luby and Ashley Styczynski from Stanford. The globe-spanning team also included Bangladeshi non-profit GreenVoice.