Mandatory Mask Use Could Have Saved 40,000 Lives, Study Says

(Bloomberg Businessweek) -- It’s clear by now that face masks save lives by hindering the spread of Covid-19. But some people continue to argue that mask mandates are intrusive and unnecessary because most people can be counted on to do the right thing for their own and their families’ safety.

In fact, mandates are essential, a new study finds. Using statistical analysis, it concludes that 40,000 lives would have been saved in two months if a national mask mandate for employees of public-facing businesses had gone into effect on April 1 and had been strictly obeyed. The analysis was for the months of April and May; presumably even more lives would have been saved if a mandate had been in place up to the present.

The study is by Victor Chernozhukov of the Massachusetts Institute of Technology and Hiroyuki Kasahara and Paul Schrimpf of the University of British Columbia’s Vancouver School of Economics. It was published online on July 7 by the Center for Economic Policy Research.

The idea that lockdowns and other mandates are unnecessary is commonly heard on social media. Florida Governor Ron DeSantis hasn’t mandated masks statewide despite a surge in infections. A paper presented at a Brookings Institution conference in June argued that educating people about risks may be the most valuable intervention because “people practice social distancing in reaction to information and apprehension regarding the virus, not just in reaction to state closure or reopening mandates.”

To measure the effectiveness of mandates, Chernozhukov and his co-authors compared death rates from the virus in places that mandated masks early vs. places that imposed mandates later or not at all. They controlled for other factors that contribute to the lethality of the virus, such as density and the age and health of the population, other government mandates, and changes in behavior. They found that mask mandates had a strong impact over and above the effects of voluntary and involuntary changes in behavior such as social distancing.

They estimated that mandating masks for employees in public would have reduced the death toll by 40%, or about 40,000 lives, with a 90% chance that the actual number would have been from 17,000 lives to 55,000 lives. “Mandating masks is an attractive policy instrument especially because it involves relatively little economic disruption,” they concluded.

The researchers were unable to measure the effectiveness of school closures with any precision because all parts of the country shut their schools at about the same time in March, making it hard to compare outcomes among areas that did and didn’t close them.

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