Every credible health expert in the world says wearing a mask will significantly reduce the transmission of COVID-19. Evidence now indicates that even a simple cloth mask can help protect both the wearer and people the wearer comes into contact with. The University of California San Francisco just published an article that effectively summarizes the scientific case for wearing a mask. Here’s an excerpt:
A recent study published in Health Affairs, for example, compared the COVID-19 growth rate before and after mask mandates in 15 states and the District of Columbia. It found that mask mandates led to a slowdown in daily COVID-19 growth rate, which became more apparent over time. The first five days after a mandate, the daily growth rate slowed by 0.9 percentage-points compared to the five days prior to the mandate; at three weeks, the daily growth rate had slowed by 2 percentage-points.
Another study looked at coronavirus deaths across 198 countries and found that those with cultural norms or government policies favoring mask-wearing had lower death rates.
Two compelling case reports also suggest that masks can prevent transmission in high-risk scenarios, said Chin-Hong and Rutherford. In one case, a man flew from China to Toronto and subsequently tested positive for COVID-19. He had a dry cough and wore a mask on the flight, and all 25 people closest to him on the flight tested negative for COVID-19. In another case, in late May, two hair stylists in Missouri had close contact with 140 clients while sick with COVID-19. Everyone wore a mask and none of the clients tested positive.
So please wear a mask whenever you’re in a situation where you are likely to come into close contact with people you don’t live with.
(Source: Still Confused About Masks? Here’s the Science Behind How Face Masks Prevent Coronavirus, UCSF, June 26, 2020)