Let’s take a few minutes today to talk about cloth masks. This article is not a red/blue black/white article.
The central conclusion right up front: we don’t know. We don’t know if they help, we don’t know if they hurt, we hardly know a damn thing about cloth masks and SARS-Cov-2.
Alright, let’s dive in with a refresher that is really important.
Science Moves Fast; Sciences Moves Slow
From Hippocrates nearly 2,400 years ago until the late 1800’s there were nearly no advances made in clinical medicine.  Until the 1600’s there wasn’t even a scientific method used to figure out if our theories on how the world worked were even right!
In a nutshell, the scientific method is as follows:
- Define a question
- Gather information and resources (observe)
- Form an explanatory hypothesis
- Test the hypothesis by performing an experiment and collecting data in a reproducible manner
- Analyze the data
- Interpret the data and draw conclusions that serve as a starting point for new hypothesis
- Publish results
- Retest (frequently done by other scientists)
Do not skip over #8. At the point where you can reproduce a study (steps 1-7) and get the same or similar results is that point at which your hypothesis (#3) becomes theory and part of accepted scientific knowledge. A single published study does not a scientific fact make.
We live in a world where due to increased communication, resources and technology we are able to make advances in science faster than ever before. At the same time, this typically happens over years (or decades) of running the questions through the scientific method. #8 rarely, if ever, happens in weeks. Which, compared to 2,400 years of Hippocratic stagnation isn’t bad.
Between #7 and #8 there is really a step #7b, where scientists basically rip apart each other’s work. Often, this is a sign of respect, your study was good enough to draw attention from other top scientists. This is the point where uncertainty is identified (not resolved) and typically more questions are thrown into the mix to be answered when the next person goes to try to reproduce the study. This discussion, while transparent in scientific journals, is typically done without the public realizing it happened at all.
This is normal. However, at present, this discussion is playing out with much more public visibility than we are used to.
The Tests & Data (#4 & #5)
Outside of medicine and other sociological fields this is pretty straightforward. You need to gather data and test a hypothesis on mice? Not hard to come by mice or do your test. Medicine constantly raises thorny ethical issues and sometimes you just don’t have data available even if the ethics are laid aside. Sometimes, you need to wait for an opportunity to appear to test appropriately.
Cloth Masks & SARS-Cov-2
Which brings us to cloth masks. You know what we have in western countries? We have N95 respirators and surgical masks in great supply…. up until January 2020. You get easily get an N95 mask at The Home Depot for your own home improvement project up until a couple months ago. They were cheap and plentiful.
Given that high quality masks were cheap and in great supply (and well tested) you know what we didn’t look at? We didn’t even think to the 100 different ways laypeople could create, wear and implement cloth masks. Just wasn’t an issue.
The first paper we at JM Addington even saw on it was titled, “Rapid Expert Consultation on the Effectiveness of Fabric Masks for the COVID-19 Pandemic.” Rapid means, “we did this as fast as we could,” “Expert consultation means,” we didn’t actually do a study — we looked at some other stuff.
This paper had, in our view, two primarily conclusions. Conclusion #1:
Therefore, we have only limited, indirect evidence regarding the effectiveness of such masks for protecting others, when made and worn by the general public on a regular basis. That evidence comes primarily from laboratory studies testing the effectiveness of different materials at capturing particles of different sizes.
I.e., we don’t know much, and what we do know is not from real world scenarios.
The evidence from these laboratory filtration studies suggests that such fabric masks may reduce the transmission of larger respiratory droplets.
In short, “cloth masks maybe help based on looking at some fast non-real world studies but we really aren’t sure.“
And we’re not even diving into into the issues of:
- Small samples sizes
- Wearing masks right/wrong
- Whether blocking large droplets is effective in reducing transmissions 
- No reproduction of results (step #8)
Are Cloth Masks Bunk?
A well-trained scientist would probably say that wearing a cloth mask or not wearing one is not even wrong yet. To say, “we don’t have evidence,” means that we don’t have well-designed controlled studies that have been re-produced to show that we know we are right. Scientists don’t like to say that they know until they know that they know that they know.
So: cloth masks: the jury is still out.
What about Particle Sizes?
We’ve seen a number of posts proclaiming that cloth masks can’t work based on the size of the gaps in the mask versus the size of Sars-Cov-2 particles. First, this argument completely bypasses the scientific method where we test ideas. Second, it still isn’t sufficient to render masks useless. To steal an analogy, imagine an NFL team trying to run onto the field through a bedroom-sized door: while they can each fit through they can’t all run out together at the same speed. Masks don’t need to be 100% effective in blocking virus particles to still prevent enough from getting through to reach the level needed to infect another person.
Why Are We Being Asked to Wear Cloth Masks?
Cloth masks are wholesale thinking, not retail. The goal isn’t to protect any one person: it is to drive down the effective reproductive number, aka Rt. Rt measures what the current transmission rate of the virus is across a population. (It is not the same thing as R0.) In the early stages of an epidemic, the goal is typically to contain the epidemic before it gets bigger and becomes a pandemic. For examples, SARS, MERS and Ebola have all been effectively contained epidemics.
At this point, public health strategy has turned to mitigation, trying to slow the virus’ growth. Stopping it outright has become effectively impossible.
No one mitigation method will be or needs to be a silver bullet, the strategy is that if enough of the population practices enough of the measure you can drive the Rt number low enough that the epidemic locally either stays stable or actually decreases. Mask wearing is one of these measures. It doesn’t need to be anywhere near 100% effective by itself in order to drive the Rt number low enough in combination with other measures to make a real difference.
Should I Wear a Cloth Mask?
If we got into the amount of uncertainty that exists around social distancing, what the Sars-COV-2 is going to do on its on you’d feel really crazy by the end. We don’t pretend to have an answer.
Your author will give his personal view. It doesn’t hurt me to wear a mask, and I believe that I have one of the better ones that could reduce transmission at any rate. The purpose of all the things we are doing, social distancing, masks, limited retail/restaurant/church capacity is meant to slow SARS-Cov-2 so that the overall pandemic stays flat or goes down. No one thing other than God himself eliminates it.
If wearing a mask inside Target, Kroger, my church, at my clients’ places of businesses, helps to keep the virus manageable so that we can continue to live normal-ish lives I’m all for that. I own a business that makes more money in a normal economy, I have eight kids, I don’t like being sick, I like eating out at restaurants. For all these reasons if keeping the virus in check is important to me. Physically and financially.
If you look at the data and think it doesn’t make enough of a difference to wear one I also don’t begrudge you. You are right, the jury is still out.
At the end of the day, it is our collective responsibility to remember that it is humanity against the virus: not dems vs reps, red vs blue, or mask vs no-mask. It is up to all of us to do our part to fight this damned thing from hell however we see fit and condemn the virus and love our brothers and sisters.
 I haven’t seen anyone who thinks a cloth mask significantly reduces aerosol transmissions, but it isn’t clear what role these smaller droplets play in transmission.