Study finds face masks prevented thousands of COVID-19 cases. Experts say you should keep wearing them.

Other research says universal face mask use could reduce the death toll from COVID-19 in the U.S. by 33,000.


While many Americans still debate whether or not to wear face masks, a new study found that face mask use has prevented thousands coronavirus cases.

The study, published in the journal Health Affairs, estimates between 230,000 and 450,000 COVID-19 cases were prevented in states that required face masks between April 8 and May 15.

Researchers said wearing face masks in public reduced the daily number of coronavirus by as much as 2% in Washington, D.C. and the 15 states that mandated face mask use compared to states that did not.

The longer face mask mandates were in place, the study found there was a higher reduction in COVID-19 cases.

Researchers also looked at 20 states that enacted employee-only mandates instead of public face mask use, but did not find a significant impact on the spread in those locations.

The study was unable to measure the actual use of face masks in specific communities and researchers were only able to measure confirmed cases of COVID-19, despite evidence that infection rates in some areas were higher.

Researchers from the University of Washington say universal face mask use could reduce the death toll from COVID-19 by 33,000.

The university's latest projection says more than 179,000 Americans will die from coronavirus by Oct. 1.

"For pretty much every state that we've looked at, if we can get people to wear masks, we can not only save lives, but I sort of think of it as we can also save the economy because we can keep business going," said Dr. Chris Murray of the University of Washington's Institute for Health Metrics and Evaluation.

More than half of the U.S. is now seeing an increase in week-to-week cases, with California, Florida and Texas setting records for single-day coronavirus case reports.

"You need to understand COVID-19 is still here, it's spreading faster than ever before," Texas Gov. Greg Abbott said.

Health experts say progress is being made on a vaccine, but, in the meantime, erring on the side of caution is best.

"We have evidence, early evidence, that masks can reduce transmission even up to six-fold," said Dr. Sanjay Gupta, CNN's chief medical correspondent. "I think it's clear that they can save lives."