Recently, Dean Blumberg, MD, chief of pediatric infectious diseases at UC Davis Children’s Hospital spoke on a college livestream about coronavirus and explained the benefits of wearing the mask. He said that wearing a mask reduces the wearer’s COVID-19 infection risk by 65%. A proper standard rectangular closed surgical mask will reduce the mask wearer’s risk of catching the virus. He also said that homemade masks “should work quite well. N95 masks, he said, are the most powerful but should be reserved for medical workers.

He further explained that the masks provide a physical barrier to the respiratory droplets of people which are about one-third the size of human hair. These droplets are a major cause through which virus is transmitted. But even surgical masks are not sufficiently airtight to create an effective barrier against much smaller aerosol particles which can be up to 1/100th the size of a human hair, he said. The best defense not to encourage particles from aerosols to cause any trouble is social distancing and not engaging with people outside. 

The issue of the effectiveness of the face masks or scientific evidence that mask reduces COVID-19 infection risk have been argued since the beginning of the pandemic. Not wearing them was not an option even during the early days of the pandemic. But now, it is compulsory to wear them since studies in laboratory conditions confirm that the virus stays alive in aerosol form with a half-life on the scale of hours. It persists in the air. 

Blumberg said “People who say ‘I don’t believe masks work’ are ignoring scientific evidence. It’s not a belief system. It’s like saying, ‘I don’t believe in gravity. You’re being an irresponsible member of the community if you’re not wearing a mask. It’s like double-dipping in the guacamole. You’re not being nice to others.”