Medical Examiner

Masking the Problem

A professor of medicine explains why he thinks face masks aren’t the best protection method at our disposal.

A worker sifts through at face masks on a conveyor belt, positioned next to another box of face masks.
A worker examines face masks at a factory in Changhua County, Taiwan, on April 29, 2009. Reuters/Pichi Chuang

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In the past few days, there have been multiple reports that the Centers for Disease Control and Prevention is about to issue new guidelines saying the general public should be wearing masks when we go outside. Aaron Carroll, an Indiana University pediatrics professor and writer, is skeptical of this. He’s been looking at the worldwide data we have on the coronavirus and thinks that focusing on masks is missing the point—there are a lot of other things we should be doing first.


On Wednesday’s episode of What Next, I called up Carroll to try to figure out how to feel about masks. Our conversation has been edited and condensed for clarity.


Mary Harris: Back in February, you tweeted that masks are mostly to protect others who are sick from you. Not the other way around. So you said, please don’t waste them, and leave them for those who have a real need, like doctors and nurses.

Aaron Carroll: I’m still consistent on that. I think that is utterly true.

If we’re talking about how the CDC is changing its guidance, then, when and if it does, I would like to see the evidence behind the reason it’s doing that. I do fear there will just be a statement like, “Do this because it’s safer.” There’s a lot of wiggle room in there. The safest thing to do is never, ever, ever leave your house. And different actions that we take increase our risk. But it’s not just a binary increase or decrease—it’s how much the risk changes. And I’m not sure that that message ever gets across.


There is this chart that’s been making the rounds among people who think the public should we be wearing more masks. It shows that pandemic curve we’re all trying to flatten, separated out by country. In three of those countries that have embraced masks—Japan, South Korea, and Singapore—the curve gets flatter way faster. Should this chart should change anyone’s minds on masks?


If you look at the responses of those three countries, and what you only take home from it is masks, well, that’s just such an association-versus-causation thing. Let’s start with the fact that those three countries had been through the SARS epidemic and therefore already built facilities and resources and had procedures and plans in place for what to do when a pandemic like this showed up. Secondly, they engaged in massive distancing measures by keeping everybody at home, and they engaged in huge levels of testing. We are still not able to do anything at that level in the United States.


Also, I worry that putting on a mask gives people a false sense of security.

What do you mean when you say that?

I worry that if people put on masks, then they’ll think, OK, I’m protected, and they won’t wash their hands as vigorously or be careful not to touch their faces. Or worse, they’ll keep touching their faces because they keep adjusting the masks, or they might just start to be lax in their social distancing. I think this is how it would play out for the public.


I know people hoarding masks who are perfectly fine. And if you’re wearing a mask in public, I’m assuming you’re fine—if you’re out in public and you’re sick, you’ve ignored all the advice. We should all be sheltering in place, and if you’re sick, you should not be leaving your house.


Do you ever worry that scientists and physicians thinking about this fast-moving virus are too used to having time to figure things out? We’re living in a situation where evidence is coming two weeks late, and it feels like we’re making decisions blindly.

I don’t know that it’s taking us a long time to figure out what to do. It’s taking us a long time to do the things that we’ve figured out.

Singapore engaged in restrictions and isolation. We do none of that. For us to look at that massive amount of manpower, resources, and policy, and then take home that they wore masks and we didn’t—that’s missing the forest for the trees. Yes, Singaporeans are wearing masks. But that’s likely not what made the difference. It’s everything else they’re doing. And we’re not talking about those things at all. We’re talking about masks.


I look out my window every day, and I see people who can’t or won’t stay home. There’s an essential worker leaving on the trains to work. There are joggers and delivery people. I don’t want to take protective equipment away from a health care worker. But I might wear a mask the next time I go to the grocery store.

I think part of the reason we disagree on masks is based on where we physically are in the world. I’m talking to you from a closet in Brooklyn, so I’m in the hot spot of the country, right? And it’s very, very dense here. While you’re speaking to me from a place that’s much less dense and is not as hot of a spot. So what might make sense for me in New York City might not make sense to someone in Indianapolis.


Everyone weighs their own risk-benefit calculation and then makes a decision. But I would also ask, what are you going out for?

Only groceries.

The first thing I would say is, have them delivered because that would be safer. I mean, that’s the case for the people who can do this. We have not yet built a society where we have given everybody the freedom and the ability to make proper choices. And I fully recognize that.


When you say get groceries delivered, I go through this ethical calculus in my head where I’m like, then I’m making like the Amazon guy go to the store.

In a perfect world, we can make calculations and protect the Amazon guy and totally make sure he’s safe. But here, if I have to go to the grocery store, I don’t wear a mask because I stay as far away from other people as possible. And if you’ve read about someone coughing in your mouth, well, the thing is, the people who are sick have to stay home. That’s the only way we’re going to halt this.


I live in New York City. I don’t trust anybody.

That’s fair. Look, if we can follow the other guidelines that we’re putting out, for social distancing and how we’re supposed to be doing it, I think masks can provide a small amount of additional benefit. That is, if we are doing the other things that we should be doing.

That’s a big if.

If we’re not doing it, then yes, this other guideline clearly doesn’t apply and then this guideline can’t apply. And then you make the decisions that you need to make because people aren’t doing what they’re supposed to be doing. But social distancing is so much more important than the masks. And that’s what drives me a little bit crazy, to think the masks are an equivalent Band-Aid to this wound over here. It’s not going to be enough if we aren’t doing massive social distancing, contact tracing, and isolation, testing of the population, quarantining, all the other things we need to be doing. Masks are not going to get the job done.

So you’re saying that political leaders need to crack down more on a place like New York?

And provide everything you possibly would need to make this social distancing work. Open the spigot. Figure it out. Spend the money. We are not doing that. That’s why I’m not angry at people who have to wear a mask and go out and get food. I get it—you have not been supported correctly. Knowing that social isolation is the tool, we have to flatten the curve and then take the step of supporting people so they’re able to do that social distancing. But we’re not doing that either.

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