I was stimulated to write this column by an event I witnessed a week ago while waiting in line to enter a grocery store. The young lady who was allowing just the right number of people to enter the store was wearing a mask and sitting in a lawn chair near the entry door. A man, who was wearing a mask pulled down below his nose, approached her to speak to her. As he bent down, putting his face near hers, he pulled his mask all the way down below his chin, completely exposing his mouth. After he delivered his message, he walked away and put his mask up where it should have been the whole time, covering his nose and mouth.

Perhaps I don’t need to say what was wrong with that performance. I hope everyone already knows. But I am concerned that a significant fraction of our population does not know how to use a mask properly, or why.

A mask is supposed to filter the air that you breathe in (inhale). It keeps airborne germs from getting into your lungs and making you sick. It is also supposed to filter the air that you breathe out (exhale) to keep the germs that you exhale from being inhaled by other people. A mask only works if it is in place between your breathing passages (your nose and mouth) and the air around you. If it is not worn over your mouth and your nose, it loses almost all its effectiveness. You might as well not be wearing it.

That is the crux of my message. If you are going to the trouble of wearing a mask, you should wear it properly to get the most bang-for-your-buck.

Here are some other interesting facts.

Viruses are so small that they can pass through masks. But in order to survive, they have to be encased in a moisture droplet, like what shoots out of a person’s mouth and nose when they sneeze or cough. A moisture droplet is usually big enough to be trapped by a mask. An infected person is most infectious when sneezing or coughing. Millions of virus particles shoot out of a person’s nose and mouth at great velocity and travel many feet, surrounded by mucous that keeps the virus alive for at least a few minutes. Viruses in large droplets survive longer than those in small droplets.

From most to least dangerous, here is the “danger-rank’ of respiratory activities:

• Sneezing and coughing.

• Speaking and singing.

• Breathing.

Yes, even just plain breathing can release virus particles from the lungs of an infected person.

It is extremely important to wear a mask properly. It just makes sense. If your mask does not cover your mouth and nose, you might inhale virus-laden droplets that your mask would have filtered out. And your mask will not be able to stop virus-laden moisture droplets from shooting out when you cough, sneeze, speak, or even breathe. You might become a “super-spreader.” (Super-spreaders don’t know they are super-spreaders during the first four or five days of their illness because they have no symptoms until their lungs are full of virus.)

COVID-19 is a serious disease requiring serious measures and wise leadership. Experts have set the rules for us to follow. Our elected officials should lead by example and wear masks properly in front of cameras.

Ben Lounsbury, MD, is a retired ENT. He lives in Auburn.

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