4:13 PM, Feb 27, 2020


Ask Dr. Nandi: Widespread facemask use could shrink the 'R' number and prevent a second COVID-19 wave: study

Posted at 6:37 AM, Jun 11, 2020

A British study suggests that a second wave of COVID-19 might be prevented if people wore facemasks in public. The researchers found that even homemade masks could lower the reproduction number and reduce transmission rates.

You know there was not a lot of research on masks when the coronavirus first started. So this study, which was led by scientists at Britain’s Cambridge and Greenwich Universities, it really helps to show what an impact a mask can have.

Now what the researchers did, was to create computer models. They looked at how effective different masks are and their impact on the virus’s spread. They also looked at the different stages of infection, social distancing, and various lockdown situations. And what their modeling scenarios showed, was that if 50% of people routinely wore masks, that the reproduction number could be as low as 1.0 when combined with social distancing and periodic lockdowns.

That’s great news because keeping the number under 1.0 will help the pandemic to slow.

Please do not wear a mask only when you have symptoms. Because the scientists’ modeling scenarios showed that if folks wore masks all the time when outside their home, that the masks are twice as effective at reducing the reproduction number, then if masks are only worn when a person has symptoms.

Even homemade masks made from cotton t-shirts or dishcloths work. As long as your nose and mouth are covered. And I can’t stress how important it is to keep them on at all times.

I’m sure you’ve seen folks wearing them and then they pull their mask down to speak to you. That is not helpful. If you pull your mask down, then it’s not going to catch airborne droplets that might be carrying virus particles. These can be exhaled not just when talking but also when coughing, sneezing - even breathing.

So I encourage everyone to wear a mask when you’re out in public. It’s something that we all can easily do. And to help you remember, keep this saying in mind: “my mask protects you, and your mask protects me”. And together, we can really help lower the numbers and contain the virus’ spread.

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