Of course this is the best possible outcome and not every case can be presented, but compared to what happens when masks aren't worn and other examples, the science is clear - proper masks are very helpful.
Hair Stylists Infected With COVID-19 Were Wearing Masks Along With Their 140 Clients—Tests Prove No One Got Sick
It seemed like the stuff of a quarantine nightmare. Two Missouri hair stylists started feeling ill just one day after returning to work at their salon. They ended up testing positive for COVID-19—but not until they had already given haircuts to 140 clients.
Public health officials in Springfield braced for the worst as all those who’d had appointments with the two Great Clips stylists went to get tested. When the results came back, they were shocked—and relieved—to find that not one of the salon customers had tested positive.
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In addition to requiring clients and employees to wear masks, public health officials also say that social distancing policies such as spreading out patron’s chairs in the waiting room and staggering appointments were also helpful in preventing infections.
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While no method of preventing transmission of the virus is 100% effective, this incident is just the latest in a string of scientific studies illustrating the dramatic impact of wearing masks. Perhaps most notably, researchers from the University of California–San Diego, Caltech, and Texas A&M found that the spread of COVID-19 in Wuhan, China was found to be much less severe than in New York and Italy because its citizens were already prone to wearing masks against air pollution.
Hair Stylists Infected With COVID-19 Were Wearing Masks Along With Their 140 Clients—Tests Prove No One Got Sick
It seemed like the stuff of a quarantine nightmare. Two Missouri hair stylists started feeling ill just one day after returning to work at their salon. They ended up testing positive for COVID-19—but not until they had already given haircuts to 140 clients.
Public health officials in Springfield braced for the worst as all those who’d had appointments with the two Great Clips stylists went to get tested. When the results came back, they were shocked—and relieved—to find that not one of the salon customers had tested positive.
...
In addition to requiring clients and employees to wear masks, public health officials also say that social distancing policies such as spreading out patron’s chairs in the waiting room and staggering appointments were also helpful in preventing infections.
...
While no method of preventing transmission of the virus is 100% effective, this incident is just the latest in a string of scientific studies illustrating the dramatic impact of wearing masks. Perhaps most notably, researchers from the University of California–San Diego, Caltech, and Texas A&M found that the spread of COVID-19 in Wuhan, China was found to be much less severe than in New York and Italy because its citizens were already prone to wearing masks against air pollution.