A team from the University of California Davis Children’s Hospital has found that covering the nose and mouth decreased the risk of COVID-19 infection by 65 percent.
Previously, researchers believed that mask-wearing was only beneficial to prevent transmission of the virus to others.
‘Everyone should wear a mask,’ Dr Dean Blumberg, chief of pediatric infectious diseases at UC Davis Children’s Hospital, 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.’
There are two main methods by which the coronavirus spreads with the first being via droplets that are expelled into the air when a person coughs or sneezes.
Researchers say these droplets are about one-third the size of a human hair, but visible to the naked eye.
The second way is from aerosol particles that humans spray into air when we speak, which are one-onehundreth the size of a human hair and nearly impossible to see.
This method is more dangerous in terms of transmission, but can be lessened by avoiding crowded indoor spaces.
‘Studies in laboratory conditions now show the virus stays alive in aerosol form with a half-life on the scale of hours. It persists in the air,’ said Dr William Ristenpart, a professor of chemical engineering at UC Davis.
‘That’s why you want to be outdoors for any social situations if possible. The good air flow will disperse the virus. If you are indoors, think about opening the windows. You want as much fresh air as possible.’
The way to think about that is to think about smells. If the person on the other side of a cubicle or plexiglass is wearing perfume, eventually, you’ll smell it’, he said.
‘The aerosol particles are small enough to travel on air much like aromas. That’s why air flow is so important, along with other actions like wearing masks and social distancing.’
The team says continuing to follows mask mandates and socially distance will help get the pandemic under control.
‘So we don’t know who might spread it,’ Blumberg said.
‘We do know social distancing reduces the risk of transmitting the virus by 90 percent, and wearing masks decreases the risk by 65 percent.
‘Wearing a mask affects everyone,’ he said. ‘If you care about your family or friends, or if you care about your community, wear a mask.’