Do face masks work?

And should I start sewing my own?

Welcome to Not a Doctor, the only (free!) newsletter about health and science that tells you when to break out the sewing machine and go full-on Little House on the Prairie.

I’m Melody Schreiber, a journalist and the editor of What We Didn’t Expect (Nov. 2020). I’m not a doctor, or a scientist, or really an expert of any kind. (Unless you count problematic pioneer novels! I have read many of them.)

I’ve seen some questions swirling around about face masks. Do they work? Do you need them? Should you start making your own?

Let’s dive in!

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Do medical masks work?

Short answer: Yes, they seem to work in providing some protection from the coronavirus — that’s why healthcare professionals need them.

Long answer: They work best in some pretty specific instances.

Before I dive into those instances, first I want to talk about the different types of masks out there.

There are the N95 respirator masks. These are the Cadillac of disposable masks because they filter out small particles, including viruses like SARS-CoV-2.*

Normally, the virus is transmitted through droplets, scientists believe. They tend to be a bit heavy, and if they don’t land on you or a surface, they fall to the ground.

But there are some cases when the virus is aerosolized* — basically, the droplets become much, much smaller and can float in the air for longer. This doesn’t seem to happen very much with normal coughing or breathing with this coronavirus. It’s more likely to happen when a patient is intubated or undergoes dental work.

That’s why N95 masks are so helpful for medical workers. They’re around people with the virus who are intubated way more often than anyone else, and so they have more potential exposure to aerosolized virus particles, which the mask filters out.

But in order to work properly against this virus, the N95 masks need to form a tight seal over your face — which can only be determined by some pretty extensive fit tests. Otherwise, the virus can get in (and out, if you have the virus) as you breathe.

Leora Horwitz @leorahorwitzmd

Non medical friends, let’s have a chat about masks. So, you’ve bought yourself a box of N95 masks and you think you’re good for #COVID19. Let me tell you what my hospital makes me do EVERY YEAR to make sure my N95 mask fits (yes, they come in sizes). Watch out: long thread ahead!

Then, there are surgical masks. (Fun fact: apparently surgical masks became popular after the 1918 flu pandemic! The more things change…)

These masks are still disposable, and they help filter out some droplets, but they don’t filter out aerosols. That means anyone wearing a surgical mask around an intubated patient could still be exposed to tiny particles of the virus.

But some protection is better than none for people who are in close contact with very sick people. As the U.S. faces an alarming shortage in masks, even surgical masks are being rationed and reused for days and even weeks on end.

(Normally, these masks are carefully taken off and thrown out after seeing each patient, let alone each day.)

Both N95 masks and surgical masks can also be useful for medical workers who are showing symptoms — of COVID-19* or any other respiratory illness — in order to protect their patients. For most people, masks are a way to keep others from getting whatever virus you have — not a way to protect yourself from others.

Photo: Mich225/Flickr

Finally, we have cloth masks. I’ve seen these in many places with high rates of pollution — in Nepal, for example, they’re a fashion statement of sorts, with lots of different colors and designs.

These masks can help filter out some larger particles, like bits of wood smoke or exhaust, but they do not seem as effective at keeping you safe from viruses. (I’m certain this pandemic will launch plenty of research on this topic, though.)

Cloth masks seem to be better than nothing if you want to protect others from your illness, but they don’t seem effective at keeping you from getting the virus (more on this later).

In the face of medical mask shortages, some clothing designers have begun using their sewing machines for good to churn out makeshift masks. But these masks don’t seem to be the kind of cloth masks you might find in an online sewing pattern; instead, they’re modeled after surgical masks, with some even using medical-grade materials.

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What’s the problem, then? Why shouldn’t we be using masks as well?

If we had an overabundance (or even an adequate supply) of N95 and surgical masks, that probably wouldn’t be a bad idea.

It’s not clear how well these masks protect the average person from getting the virus at, say, the grocery store. But with a virus that’s asymptomatic or mildly symptomatic in a significant number of cases, it would be nice if people were able to protect others from whatever they’re carrying in their bodies.

Unfortunately, right now masks in the United States should be going to health workers, who are exposed much more often and to much higher levels of the virus, because those who are sickest seem to be the most contagious.

There’s one exception to this: If you are caring for someone with a confirmed case of COVID-19 — basically, you are their health care worker — then the CDC* recommends wearing a medical mask.

There are also a few caveats to using masks that could make them useless or even potentially dangerous for the average person to use.

First, you need to know how to take them on and off without contaminating yourself — and this is harder than it sounds.

For instance, if you touch a part of the mask that has trapped virus particles on the outside of it, and then you accidentally brush your face as you unloop the ear ties, you could expose yourself right then and there.

Or if the mask isn’t fitted closely enough to your face, you could actually trap particles in the area you’re trying to keep them out of — which, yeah, sounds bad.

Second, realtalk: Masks can feel kinda itchy and just downright weird. It’s strange to have something up against your face, and it’s hard to talk with them on. If you’re not used to wearing them, you might be tempted to adjust them — which means you’re touching your face! No face touching!!!

Third, if you think you’re being protected by a mask, you might have a false sense of confidence about your risk of getting the virus. You might not take the same level of precautions — venturing out into public more, or forgetting to wash your hands as much as you should.

As faithful readers of this newsletter know, that not only puts you in danger of getting sick — it also puts everyone with whom you come into contact at risk, too. And that’s bad!

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Should I get all Little House on the Prairie and make my own?

It’s probably a good idea to have some kind of mask or bandanna to cover your nose and mouth in case you get sick and need to go out for some reason (for example, if you need to go to the hospital to be tested).

Cloth masks help contain some of the droplets that get out as you breathe and cough. They would provide some level of protection for the people around you, especially as your test is being confirmed or if you’re being cared for by a family member and you’re unable to get medical masks.

But in terms of protecting you from the virus, cloth masks do not seem very useful. One study found that about 97 percent of virus particles still came through a cloth mask. Plus, there are the usual dangers of contaminating yourself and unintentionally taking more risks, as with other masks.

That study also showed wearing a cloth mask may actually increase your chances of getting sick. The mask can become a little moist as you breathe in and out, trapping the virus up against your nose and mouth. That sounds like not what we want!

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Masks only go so far

Masks are only part of what helps protect health workers. For example, you can also get the virus by touching your eyes. Face masks, you might have noticed, don’t cover your eyes. (This is probably a good thing.)

Medical staff working with COVID-19 patients suit up in other protective gear as well: face shields, protective eyewear, aprons.

And they take other very important precautions, including constant handwashing and, when possible, keeping some distance from a patient.

You don’t need a bunch of medical gear to do that — handwashing and maintaining a six-foot distance are still some of the most reliable ways to protect yourself and your loved ones.

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Glossary

aerosolization: when a liquid — in this case, droplets containing a virus — disperse into the air in very small amounts and linger for a time

CDC: The U.S. Centers for Disease Control and Prevention

COVID-19: A form of pneumonia caused by the virus SARS-CoV-19

SARS-CoV-2: The coronavirus that causes the disease COVID-19.

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As always, please leave a comment below or email me with any questions, concerns, feedback, or sewing tips at melodyaschreiber@gmail.com.

In the meantime, if you know someone who might appreciate this newsletter, please feel free to forward it to them.