The duplicity of mask "science": Introduction

Within certain circles in the US, it’s become gospel that masks are an effective tool to reduce the spread of COVID-19. How did this happen?

We’ve been led to believe that an group of brilliant scientists had a meeting one day, did a bunch of clever experiments that you and I would never understand, and conducted an impartial review of the available data. Then, the Center for Disease Control (CDC) relayed the findings of those scientists to us.

That is not what happened. It’s just not how science works in real life. Even in the best of times, science is a slow and difficult cycle of hypothesis and experiment, weighed down by the bureaucracy of university administrators and the petty rivalries of peer reviewers. It can take decades for good science to reach a firm conclusion.

What happened is that people (especially politicians, who need to look like they are doing something to fight the pandemic and who love to paint their political opponents as “science deniers”) clamored for a solution to COVID-19. It fell upon the CDC and similar organizations around the world to provide such a solution. They chose masks, not because the data made them look promising, but because they were convenient and plausible. Then they funded slanted studies purporting to show their efficacy. They cited those studies on their website, trusting that the big science-y words would discourage most people from actually reading them and seeing how flawed they are.

It was crucial for the CDC to ignore and downplay the fact that humanity has had to contend with respiratory infections and pandemics for hundreds of years. We already knew a lot about what works and what doesn’t. That’s why no one recommended mask wearing for the public before the arrival of The New Science. Anthony Fauci made it very clear in March 2020 that “there’s no reason for people to be walking around with a mask”. (He now claims this was a “noble lie” he told to prevent shortages of masks for healthcare workers. Make of that what you will.)

I decided to actually read the science in January, purely out of curiosity. (Yes, I’m late to the party, but better late than never.) I started with the CDC’s “Summary of studies that have assessed the effect of mask wearing on COVID-19 infection risks”. I spent many sleepless nights working through all 18 of those studies. With two exceptions, I managed to avoid reading what anyone else on the Internet had said about them, because I didn’t want to cloud my judgment.

I was appalled. These studies are full of cherry-picking, misuse of statistical models, and broad overgeneralizations. Quite frankly, they are an insult to science. They are the spark that ultimately led me to seriously doubt the entire US pandemic response.

In this series, I intend to examine each of these 18 studies in detail. My goal is not to persuade, but rather to demystify the science and provide you with the tools you need to read and evaluate these studies and others on your own. In fact, if you are already familiar with statistics and study design, you don’t need to read this series. I don’t really even want you to read it. I’d rather you read the papers carefully yourself and come to your own conclusions about their quality.

Before we dive in, let’s get a few questions out of the way.

“I disagree with something you’ve written about one of the studies.”

Great! It’s very possible I’ve missed something or gotten something wrong. Please write a comment explaining your disagreement. I would love to discuss it with you.

“What about a different study that isn’t on this list?”

Please write a comment with the name of the study, and I’ll try to take a look.

“What about N95’s?”

The short answer is that N95 respirators have significant filtration efficiency for particulate matter, including SARS-CoV-2 bioaerosols, when worn correctly. The long answer is much more complicated, and I plan to write about it eventually. Be patient.

“How were there so many fewer deaths from the flu in the 2020–2021 flu season than in previous seasons?”

I don’t know; I’m not a virologist. Some have suggested it’s a result of cross-reactive immunity, viral interference, and/or competing risks. Regardless, this is not a new phenomenon: infectious disease researchers have noted that “there is often just one dominant respiratory virus in a population at a given time”. For example, influenza A also disappeared during the 2009 H1N1 pandemic, during which virtually no restrictions were in place.

It definitely, definitely, definitely wasn’t primarily because of social distancing and masks, as Scientific American claims. That is one of the most patently ridiculous and wildly implausible hypotheses about the pandemic I have ever seen, and it has stiff competition. There were sizable and concentrated regions of the US and the Northern Hemisphere in general where social distancing and mask compliance were effectively zero and people have been living as normal. The flu largely disappeared everywhere.

“How could masks not help? They block the droplets containing the virus!”

The New York Times has an article about how plastic barriers are ineffective at reducing transmission because they merely redirect aerosols rather than neutralizing them. Well, the same thing is true for masks: they primarily just redirect the virus through the gaps between the mask and the face. OSHA’s respiratory protection training videos make this clear: “Face masks are not designed or certified to seal tightly against your face, or to prevent the inhalation of small airborne contaminants.” (This video, which is worth watching in its entirety if you have the time, primarily focuses on the use of PPE to protect the wearer, but the same concept applies to masks used as source control.)

Emily Burns has a great series of tweets about the mechanics of mask wearing, complete with demonstrations.

“Do you have any evidence that masks don’t work?”

I think you’re unduly shifting the burden of proof, but I’ll answer your question anyway.

Before 2020, there was a strong scientific consensus that masks are not effective for reducing the spread of respiratory viruses. A highly-cited Cochrane Library meta-analysis of randomized controlled trials found no protective effect of surgical masks against influenza-like illness, which includes the flu, SARS, COVID-19, and others.

A 2019 WHO meta-analysis of randomized controlled trials of face masks against influenza found the same abject lack of effect.¹

(Of course, there were also retrospective studies that showed that masks did work against flu, or SARS, or RSV, or whatever. In 2020, people even started making meta-analyses of those retrospective studies even though higher-quality evidence was available. But no one took those studies seriously because, as I hope I will show you, you can prove anything using a retrospective study.)

For COVID-19 in particular, there have been only two randomized controlled trials on masking. They are the DANMASK trial, which found no significant effect, and the Bangladesh trial, which, well… we’ll get to that one in the next article of the series.

As for non-randomized evidence, I could tell you that statewide mask mandates in the US made no difference to case rates or that masked schools in the US suffered higher case rates than unmasked schools (and I suppose I just did), but there is no substitute for looking at the data yourself. The New York Times is a good source of US data and Our World in Data is a good source of worldwide data. Emily Oster’s survey dashboard is a good source of data on COVID-19 responses in schools, including masking.

“Sure, there may not be any good evidence that masks reduce transmission of COVID-19, but people should still wear them just in case they do.”

Fine. You have the right to wear a mask if that’s what you think. But please understand the implications of what you are doing.

1. You are acting on superstition, not science.

   “When you believe in things that you don’t understand, then you suffer.”

   Yes, it’s possible that masks have an effect on transmission and that the reason we have no good evidence is that no one has done any study sensitive enough to measure it. But such an effect would necessarily have to be very small. Also, it is just as valid to believe that masks increase transmission by 1% than to believe that they decrease transmission by 1%. (This is not implausible, because of the possibility that the weave of a mask nebulizes respiratory droplets into smaller, more infectious particles.)

2. You are making life worse for the people around you.
   I want to be able to hear you clearly and see your whole face when you talk. Masks cause stress, which is an immunosuppressant, and they can be a trigger for a traumatic event (including, for example, the COVID-19 pandemic). These responses are common enough to be recognized by the UK’s leading mental health advocacy organization.

   

   (If only the US could be this honest. All we get is “your concerns are invalid; my kid loves his mask; just shut up and follow the rules”.)

3. You may be letting fear control you.
   There is no reason for you to be afraid to take off your mask. There is no reason for you to be afraid of interacting with unmasked individuals. These are irrational fears. If someone has convinced you to be afraid of those things, you should consider why they may be interested in using fear to turn you against others.

4. You’re better than that.

   Actors don’t wear masks on TV. Athletes don’t wear masks during games. Politicians don’t wear masks during speeches (or when partying at nightclubs, or when modeling at the Met Gala, or when reading to masked children at school, or when attending sporting events with immunocompromised individuals). So why do you? Is it because you think Saturday Night Live is too important to sacrifice quality for (the illusion of) safety, but your life isn’t? Come on, believe in yourself a little. These people aren’t better than you. Stop letting them convince you that they are.

5. It’s been almost two years.

   With each passing day, the refrain of “absence of evidence is not evidence of absence” carries less and less weight. If masks really helped, we’d have seen a non-garbage study showing it by now.

“Why do you care so much? Just wear your mask. It’s not a big deal.”

Because I hate walking outside and being greeted with a gloomy crowd of anonymous, muzzled faces. I don’t want to live in a world where children, and especially disabled children, are suffering from unnecessary learning loss and speech delays. Most of all, I’m fed up with “experts” telling me what to do with no scientific justification whatsoever.

I consider masks and mask mandates to be symbolic of the failure of US COVID-19 policy as a whole. They are one of many examples of pseudoscience dressed up as consensus and used to implement overreaching and harmful policies with no exit plan. I’m not just writing this because I don’t want to wear masks anymore (though, let’s be honest, they do really suck). I want to teach you to recognize the scientific malpractice that led to this disaster so that we as a society will better be able to resist it in the future.

My biggest regret

Alright, there’s a lot to get through. We’ll start with the notorious Bangladesh mask study tomorrow.

1. Yes, I am aware that this document still recommends the use of face masks by asymptomatic individuals in severe flu epidemics and pandemics. However, it admits that this recommendation is being made as a precaution, and not because of conclusive evidence that face masks reduce transmission. And nowhere does it suggest that masks should be mandated. I write about this use of the “precautionary principle” at the end of the article.

I highly recommend reading this document in detail. It also has a lot to say about contact tracing, quarantines, and border closure.