This is the fifth of several articles about COVID-19 and related topics by Dr. Jon Crosbie, an ISU alum, sports fanatic and all-around awesome Doctor of Osteopathic Medicine.
So here’s a hot take – Darth Vader was a role model. At this point you’ve probably seen the meme where Vader starts to socially distance his force chokes.
Another reason Darth Vader was a role model was because he was wearing a mask. Granted, he had to wear one because (spoiler alert) he got outdueled by Obi-Wan Kenobi in a scene that, quite honestly, could have been much more well done, but I digress.
A friend of mine from residency who’s now a surgeon asked me to write about this about a month ago, and I should have done it much sooner. She was rather prophetic…the masks turned out to be an issue just like everything else and this would have been better timed earlier. But as the country decides to open up without the systems in place to safely manage the reopening (do NOT get it twisted…we’re not reopening properly…but we’re doing it anyway), it’s important to discuss how everybody can do their part and attempt to compensate for the shortcomings of the people who were supposed to handle this stuff.
We’ll focus on the difference between N95s you’ve heard about, surgical masks, and homemade masks including bandanas. Of course there’s a little more to the story. To understand why each works the way it does, you need to know about water droplets.
When you sneeze/cough/shout/talk/breathe, water droplets are propelled into the air from your nose, mouth, and lungs. Obviously, if you are infected with SARS-CoV-2, the virus can live in the droplets. The size of the droplets the virus can live in determines how “airborne” the bug actually is – so that’s a whole other discussion. A major point, though, is that we’re still trying to figure out just how easily the virus can be spread through the air. We’re also still trying to figure out just how much virus an asymptomatic person puts out via respiratory droplets.
When an infected droplet gets put out into the air, basically one of three things can happen to it. It can fall to the ground or a surface, it can evaporate, or it can be inhaled by somebody else — and that’s where the masks come in. But to understand the masks, you need to understand droplets.
Basically, the term “respiratory droplet” refers to a portion of water that is less than 5 microns in diameter. Okay, so what’s a micron? A micron is also known as a micrometer. It’s represented by a symbol that I can’t type in to a post because it’s so explicit (I’m kidding, it’s this: μm but I can’t find that symbol on my keyboard – I had to copy and paste that). So we’ll just go with “micron”. There are a thousand microns in one millimeter. There are a million microns in 1 meter. Because most of you reading this live in America, how about this – there are 25,400 microns in one inch.
Now, respiratory droplets bigger than 5 microns generally tend to fall to the ground rapidly. They aren’t thought to get beyond 3 feet out before they fall to the ground. This is different than something called a “droplet nuclei,” also known as “aerosols.” Those are itty-bitty droplets <5 microns. Those can stay suspended in the air longer. We know definitively that influenza viruses can live in droplet nuclei and can travel greater than 1 meter (about 3 feet) to infect people. Another bug we know can live in droplet nuclei is tuberculosis.
How big of droplets can SARS-CoV-2 live in? How easily transmittable is it through the air? Currently, the jury is still out on that. There’s some anecdotal evidence that would suggest it can move through the air relatively easily – there was a choir practice in Seattle that happened back in late February. They all practiced social distancing and stayed 6 feet away from each other, but 9 people at the practice were infected and two died. This would suggest that forceful exhalation of particles (yelling, singing, yodeling, whatever) is a way the virus can be transmitted…as such, so can coughing and sneezing.
What about talking and breathing? I dunno. Nobody does, really. It is very, very reasonable to assume, though, that more infectious particles are put out into the air by an infected patient who is coughing, screaming, or yelling, than by somebody who is simply talking or breathing quietly. There are some problems in trying to figure this out. Sorry…let’s get back to the masks….
N95 masks are known to filter out and protect people from droplets 0.75 microns and above with really good efficiency. In other words, the N95s are effective in filtering out the droplet nuclei that carry at least 2 of the bugs we know can be transmitted through the air (influenza and tuberculosis). It’s very reasonable (though not certain) to assume that droplets infected with SARS-CoV-2 are bigger than those infected by influenza and tuberculosis and are also filtered out by N95s.
By the way, this hinges on you not touching the outside of the mask. You know the bugs and the droplets are still on the outside of the mask, right? Well, they are…don’t touch your mask.
This also assumes a good face seal. People who are wearing N95s who have beards…that doesn’t make much sense. The only way you take advantage of what the N95 actually does is by making sure droplets can’t get around the mask. So, full beard + N95 = waste of an N95.
So here’s the thing…N95s are the masks that help prevent you getting sick the best. And here’s another thing…the healthcare providers get first dibs. (I fully recognize that’s self-serving, but until you’ve had to intubate a thrashing, coughing person or give CPR to somebody, you’re going to need to concede this). The simple fact here is that healthcare providers working in Emergency Rooms, hospitals, and even urgent cares are exposed to more coughing and sneezing and yelling and thrashing…they’re exposed to more infectious droplets than anybody else. The amount of exposure an ER doctor has when intubating a patient is exponentially higher than somebody who is walking through a grocery store.
So what about the other masks; what about the homemade ones? Are they of any use? Based on a study done and published in the American Chemical Society…yeah, maybe.
They designed a study wherein particles between 6 and 300 microns in diameter were blown *through* various fabrics and found that tighter weave cloth masks were pretty good at filtering some of those out. Now the effectiveness decreased as the droplets got smaller, obviously, but 2 layers of 600 TPI cotton filtered out 82% of the particles 6-300 microns in diameter, give or take. Data regarding particles <5 microns wasn’t on the study.
In other words, they were studying how much a mask filters out the droplets from your own sneezes, coughing, breathing, etc, from passing to the rest of the world.
That’s not nothing here. If you sneeze in a mask, you stop the particles from getting out and floating around, and here’s the ultimate point with homemade masks: You wear a mask because YOU might be infected. Not to prevent infection. It’s something you do for your fellow Americans.
If somebody claims to want to help America, if somebody claims they value a culture of life, this is something that person would do for their fellow man or woman.
Because here’s the other thing (to quote Donald Trump, actually):
What the hell do you have to lose?
The answer is nothing. This isn’t a hydroxychloroquine situation where there might be side effects. We don’t have to worry about heart arrhythmias here. Wearing a mask does not put you at risk for anything at all. You are in no way permanently adversely affected by wearing a mask. At all.
Well, let me walk that back exactly one half step. If you have a mask on, you have to socially distance. You have to be careful. We’re not out of the woods here and, again, the systems that should have been put in place to reopen the country simply aren’t in place. So don’t think that if you have a mask on, you can do whatever you want. That’s reckless and irresponsible.
Oh, I understand some people don’t WANT to wear a mask. That they feel less cool or that it might mess with their makeup or that it shows weakness or that because some retailers are requiring masks and this makes people feel as though their rights are being trampled on. #firstworldproblems
These are all reasons that the medical profession refers to as “supertentorial.” The supertentorial region of your brain is the part of your brain where you do your thinking and deciding and wanting. It’s above your brainstem and your cerebellum. Saying something is supertentorial isn’t a compliment. When a medical professional refers to a supratentorial problem, it’s a pejorative, and implies the problem is all in the person’s head.
Which, if someone refuses to wear a mask, is exactly where the problem lies. There’s literally no reason for a person to refuse to wear a mask, other than because they don’t care about the people around them. It is because they will not make a miniscule concession in the interest of helping people around them, even if it’s a small, probably trivial bit of help.
That might seem like a harsh assessment, but here’s one more thing: Yeah, the masks ultimately might not prove to be effective. I will readily concede this is a possibility. And…what? What have you lost? If that ever happens, if there’s ever a study where masks are definitively proven to be ineffective (and no, as of now, there have not been), it has cost you NOTHING. The risk/reward ratio here is so incredibly tilted to the side of reward, because the risk is as minimal a risk as exists.
Darth Vader. Fantastic villain. Social distancer. Mask wearer. Role model.
Dr. Jon Crosbie, D.O., is a Physician and Assistant Professor at Des Moines University Medical School.