A model from the University of Washington predicted that the US could prevent about 33,000 coronavirus deaths by October if 95% of the population wore face masks in public.
Even if people wore masks that are only 50% effective at trapping infectious particles when they breathe, universal adoption of masks would still stop an outbreak, the UK study showed.
That research aligns with findings from Arizona State University, which showed that “broad adoption of even relatively ineffective face masks may meaningfully reduce community transmission of COVID-19.”
The university’s models in April determined that if nearly everyone in New York state wore a mask, up to 45% of projected deaths over two months could be prevented — even if the masks were only 50% effective. In Washington state, the model showed, face masks that are only 20% effective but worn by most of the population could still reduce mortality by up to 65%.
Source: Business Insider