Is CDC Masking the Truth?

Do masks have a role to play in stopping the spread of COVID19?

It seems a reasonable question to ask. Many have pointed out that viruses are so tiny compared to the pores in an N95 mask that that wearing a mask to control a virus is like confining mosquitoes with a chain link fence.

The response is that viruses are spread not only as individual virus particles (aerosols), but also in water droplets that condense in our breath. If the mask can’t stop the aerosols, at least it can stop the droplets.

But public health experts have known for years that these droplets have a very short range, and they’re important only when people are indoors, in intimate contact. In operating rooms, surgical masks are routine. But in open, public spaces or out of doors, it is only aerosols that spread viruses, and the aerosols go right through the masks. Like a mosquito through a chain link fence.

On the other hand, it’s a small thing to ask, and it can’t do any harm, and millions of Americans feel earnestly that they are doing their part to pull together in a community effort to defeat a virus that threatens us all. Masks can do no harm, and maybe they can do some good.

No harm? The US Occupational Safety and Health Administration (OSHA) has for years regulated face masks in the work place, because people wearing them are getting less oxygen, and it affects alertness and reaction time in short order. For asthmatics or for runners and athletes, face masks are a bigger threat. Retail and health care workers are required to keep masks on for an entire 8-hour shift. Many have fainted, some have contracted encephalitis, and a few have died.

A generation of children is being deprived of the facial cues with which they learn to read the intentions of their teachers and playmates. Some are being shamed and ostracized when they feel uncomfortable or short of breath, and take their masks down. Almost all are being denied the experience of free play outside the classroom, which is where the best learning takes place.

So it is an important questions: Do masks work to slow the spread of the coronavirus? A Swedish economist compared 24 European countries with and without mask mandates, and he could find no evidence of benefit.

But our own CDC published an article this Spring, based on detailed mathematical analysis and a mountain of data to which only the CDC has access. They concluded that there has been a very substantial benefit from State mask mandates, and many news articles were published based on their expert analysis.

Dr Madhava Setty and I examined this paper and found much to question in its methods. What we found was hard to explain as a mistake or error in judgment. It looked to us like a deliberate deception.

The CDC article was in the format of a scientific study, with data, statistical analysis, conclusions, and footnotes. But it was published only on their web site, and was not peer reviewed. So Dr Setty and I may have been the first scientists to subject the study to detailed scrutiny. We might expect to find differences of opinion, or maybe methodology that was questionable or even statistical errors — such differences are routine, and discussion of these things is the vital process that makes science the powerful lens on the truth that it is well known to be.

But what Dr Setty and I found was more disturbing. The CDC method of analysis was so unusual and so narrow, and so much contrary evidence was ignored, that we realized it could only be deliberate. We were very reluctant to accuse anyone of deliberate deception, but here is what we found that seemed to point in that direction.

In seeking scientific evidence for the real-world effectiveness of face masks, the obvious thing to do would be to compare places that required face masks to places that did not. The CDC report did not do this. Another obvious approach would be to count the cases in the same place before and after governments required face masks. The CDC report did not do this. A third method would be to measure the rate of spread of COVID before and after the government rules. The CDC report did not do this, either.

So what was the criterion for “success” in the CDC report? It is a difficult thing to explain, and a criterion that neither Dr Setty nor I had seen in hundreds of public health studies that we have read previously. It was “defined as the difference between the natural log of cumulative cases or deaths on a given day and the natural log of cumulative cases or deaths on the previous day”. The sole evidence for efficacy provided by the CDC report was that this measure goes down after states imposed mask requirements.

Dr Setty and I knew enough mathematics to realize that this was where they put the rabbit in the hat. We knew that their measure has to go down whether the masks do anything or not. The natural log is a function that grows ever more slowly, so as time goes on, the difference that they describe must get smaller. This was by no stretch of the imagination a fair test of whether masks work, but it was couched in mathematical language so that most people — even most medical researchers — would never realize that the game was rigged.

The “difference between natural logs” that the CDC used as their measure was going down at the beginning of the pandemic, before anyone was required to wear masks, and it was going down afterward. It was going down in places where people wore masks, and it was going down where no one was wearing masks. It was going down for mathematical reasons, because that is what this function does. It says nothing at all about whether masks can stop the spread of COVID.

Did the authors of the paper know this? We believe that they must have. It’s a “mistake” too erudite to be made by anyone but a well-trained statistician. The authors asked this mathematically complicated question, and did all the analysis to compute an answer. Are we to believe that they never asked the simple questions? Could it be that they did not realize that case counts were continuing to go up after mask mandates? I believe that they started with the simple questions, but the answers they found did not accord with a pre-formed agenda.

It is thinking like this that brought Dr Setty and myself, reluctantly, to suggest that the CDC knew exactly what they were doing when they ordered this deceptive paper to be written, then posted it on their web site, without scientific peer review, but with a big press release, promoting the conclusion that “masks work” (for example).

Postscript: Giving these CDC scientists the benefit of the doubt, we sent the lead author a copy of our paper before we submitted it for peer review. All our concerns about the CDC methodology were spelled out, in far more detail, of course, than I am able to convey in this article. The result was that last week, CDC published a correction. Here is the mistake that they acknowledged:

“the third sentence in the first paragraph should have read, ‘Starting in April, 38 states…” rather than 39 states, as in the original version.

The CDC is charged with a public health responsibility that is central to every American. They collect and disseminate the information that governments rely on to make policy decisions, and that we all rely on to make rational health choices. If the CDC is not protecting our health, who are they protecting?