COVID-19: “Airborne” (transmission–not the nutrition supplement that won’t work here)

So, there’s been a lot of talk about COVID-19 being airborne and I thought it would be important to detail a few aspects of something being airborne, not airborne, and what exactly that means.

If you watched the movie “Outbreak”, you might remember Dustin Hoffman in a hospital following the ventilator ducts into a patient’s room and then delivering the ominous line, “It’s airborne…” meaning that Motaba spread like the flu. And then all hell broke loose.

So, is COVID-19 airborne or not?

That’s not as easy an answer as you might think…because “airborne” isn’t a yes-or-no, black-or-white thing. Airborne exists on a continuum; airborne is more of a gray area. Let me explain…

Pretty much any respiratory virus can be transmitted through respiratory droplets. The question is, how small can the droplets be and still be able maintain an infectious virus particle? See, the smaller the particle, the longer it can stay suspended in the air. So let’s set some parameters on our spectrum:

On one end of the spectrum, we have rhinovirus—the virus that causes the common cold. Rhinovirus likes to live in nasal secretions, but can live in large and medium-sized respiratory droplets. That’s not the way that it’s usually spread though. Rhinovirus prefers to spread itself through something called self-inoculation. That’s when somebody with rhinovirus wipes their nose and then touches something like a keyboard or a phone or whatever and then you pick up that object and then wipe your nose. Then you get rhinovirus.

That’s how rhinovirus is transmitted, because it survives better and longer in nasal secretions than it does in respiratory droplets. It CAN survive in larger respiratory droplets, so if somebody with rhinovirus sneezed right in your face, you could certainly get rhinovirus. But the respiratory droplets it likes to live in are too big to stay floating in the air, so they fall on surfaces and to the ground.

At the other end of the spectrum, there’s measles. Measles is the most infectious disease humanity has ever faced and is breathtakingly good at spreading itself. Measles can live in the tiniest of respiratory particles, and even on dust particles that stay suspended in the air for hours and hours.

If somebody with measles walked into a room and coughed, the virus would stay suspended in the air for a really long time; if you walked into the same room three hours later, you could get measles just by breathing the air. If somebody with rhinovirus did the same thing, you would not get rhinovirus.

So that’s our continuum, such that it is. On one end we have rhinovirus, on the other end we have measles. Coronaviruses—which include COVID-19—fall somewhere on that continuum, and people are working really, really hard to find out exactly where because the answer isn’t overly obvious.

How does COVID-19 spread?

We know that COVID-19 likes to spread itself through self-inoculation, just like rhinovirus. We know that COVID-19 can live in respiratory droplets and spread through airborne means, but what we don’t know is just how easily that can be done. It most likely doesn’t spread as easily as the flu through airborne means. The flu’s preferred means of transmission is respiratory droplets. It would appear that COVID-19’s preferred means of transmission is self-inoculation.

But just because something is preferred doesn’t mean it’s the only way. I prefer to eat steak, but if salmon is the only thing on the menu, I might have that. Obviously COVID-19 isn’t a thinking, calculating organism that chooses the way it wants to get into somebody’s body, but it might help to think of it that way or apply that imagery. It might be stalking us right now on the surfaces of grocery store PIN pads, but it might also be considering new ways of getting us…trying to keep itself suspended in the air as long as possible for us to breathe in.

This would be a good time to point out that the airborne nature of a virus isn’t the same thing as how infectious it is. There’s a term called R0 (pronounced “R naught”) which takes into account other factors, but that’s another post for another day.

Does wearing a mask protect me from COVID-19?

That, then, begs the question, what do we do about masks? Here’s my opinion on masks; this isn’t the CDC opinion, this isn’t the government’s opinion, this is just Crosbie’s opinion, so take it for what it’s worth.

If you want to wear a mask, wear a mask. If you have N95 masks, donate those to your local hospital. They need them more than you do because they’re intubating patients, they’re getting coughed on, they’re getting respiratory secretions all over themselves. You don’t need an N95 walking through the grocery store. Please don’t hoard the N95, when others very much need them.

Now, a homemade mask that everybody has been talking about, by all means certainly won’t hurt anything, and it might very well help. I don’t have a problem with people wearing masks when they go out, UNLESS you think the mask is adequate protection and you can now do whatever you want. You can’t. You still need to pretend you have COVID-19. You still need to pretend everybody else does too—the person who picked up the frozen pizza before you did and put it back into the freezer case…that person has COVID-19. The person who wiped their nose and used the shopping cart before you, that person has COVID-19. Remember, COVID-19 wants to infect you that way, so wash your hands and don’t think that a mask means you get to do all the things that you should be staying away from.

If you’re just going out for groceries and then going right back home—and it’s not an N95, by all means, wear a mask.

I hope that clears up what it means for a virus to be airborne. It’s not so much that it is or it isn’t, it’s how comfortable the virus is living in smaller droplets.

Reach out to us if you have questions or think you might be sick; we’ll be here if you need us.

The expert family medicine providers at the Des Moines University Clinic are here to help you and your loved ones stay healthy year-round. If you think you or your family have been infected with COVID-19 and live in Polk County, call 2-1-1. If you have an upcoming appointment at the DMU Clinic please call in advance. More information is available on DMU’s coronavirus response website.

Disclaimer: This content is created for informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified health care provider with any questions you may have regarding a medical condition.

Jonathan Crosbie, D.O.

Dr. Crosbie is an assistant professor in the Departments of Osteopathic Medicine and Family and Internal Medicine at Des Moines University. In addition to his academic responsibilities and providing excellent patient care in the Family Medicine Clinic he is an avid activist for preventative medicine and living a healthy lifestyle. In his spare time he enjoys motorcycling, woodworking, movies and sports, and spending time with his family.

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