25 experts try to justify 3 years of masking. And fail.
The government of Japan will no longer request universal masking from March. To coincide with this, the government’s Covid Response Advisory Board put out a document by 25 experts citing evidence for the effectiveness of mask wearing, presumably to justify the last three years of the miserable practice and its return in future viral panics too. The document is…unconvincing.
RCT? Not for CV
Although they ignored the recent Cochrane systematic review of 12 randomised controlled trials (RCTs) that found no evidence masks make a difference for Covid or influenza, the experts forced themselves to admit little RCT evidence exists for masks stopping Covid infections.
In an RCT conducted under conditions of low mask compliance and relatively high risk of infection (in Denmark), there was no difference in the risk of infection over one month between mask wearers and non-wearers. So it’s known that mask wearing is not necessarily sufficient to prevent oneself from being infected [6].
A community-level cluster-RCT in Bangladesh found that mask wearing reduced the risk of transmission in the community [8]. However, the possibility of bias in the randomisation has been pointed out, so the causal relationship was not sufficiently proven [9].
Excuse me for being underwhelmed. I know these results are hardly news to readers of blogs such as this, but neither the Denmark RCT nor the peer-reviewed critique of the Bangladesh study was reported in the Japanese media or mentioned by these experts before. Hell, even the media reports of the experts’ document don’t mention the RCTs. So media consumers in Japan are completely uninformed of the lack of high-quality evidence for masking and will remain so.
BS from US
One study that the Japanese media loves to cite is the abysmal study in the NEJM of masking in Boston schools. The experts inevitably cite this stinking turd too.
In a 15-week observational study of elementary and junior high schools in Massachusetts, USA, when comparing children and staff at schools where the mask mandates were lifted and schools where mask mandates continued, the risk of infection was reported to be 44.9 per 1000 higher (95% confidence interval: 32.6-57.1) in schools where mask mandates were lifted [10].
Others have written about how bad this study is (e.g., Emily Burns on testing differences and Tracy Beth Hoeg on numerous other problems). But one thing that nobody seems to have pointed out is the strong positive correlation between cases and childhood vax rates. Cases and vax rates were by far the highest in the 17 districts that lifted mask mandates second and lowest in the 2 districts that continued the mandates, with the other two sets of mandate-lifting districts in between.
So if the experts want to cite this study as evidence of mask effectiveness, they first need to explain why the differences between districts aren’t due to negative vax effectiveness, which appears to have stronger explanatory potential. Or they can stop citing obvious garbage.
Timing is everything
The experts cite another crappy study.
A study in the United States suggests that mask-wearing is effective for epidemic control. A 10% increase in mask wearers was estimated to make it 3.53 times (95% confidence interval: 2.03-6.43) easier to suppress prevalence (i.e., a 10% increase in mask-wearing increases the likelihood that the effective reproduction number will fall below 1 and the epidemic will be under control by a factor of 3.53) [11].
But this study only used data from June-July 2020. As Guerra and Guerra showed, the negative relationship between masking rates and case growth in summer 2020 goes away when the early-hit, low-prevalence northeastern states are excluded and was completely nonexistent in autumn/winter.
The experts cite another study that pulls the same trick on a larger scale.
In a Bayesian hierarchy model analysis of the relationship between mask wearing and epidemic control across six continents, wearing masks in public places contributed to reducing the effective reproduction number by about 19% when the mean mask wearing level was reached [12].
This study looked at mostly countries and regions in the northern hemisphere between May and September, i.e., the summer low season in Europe and much of North America. Amusingly, the experts also cite a paper about the sociocultural determinants of mask wearing which contains the figure below. The countries highlighted are, from top to bottom, Singapore, the UK, and Sweden.
I’m no expert in Bayesian hierarchy modelling, but if masks work, why isn’t there a clear relationship between mask wearing and Covid deaths in or between the UK and Sweden? The experts might retort that Singapore had a very high mask rate and very low Covid mortality, similar to Japan.
But Spira looked at mask usage and Covid cases/deaths in 35 European countries from October 2020 to March 2021 and found “the correlation between mask usage and deaths was positive and significant.”
So either (1) masks have very different effects along different lines of longitude or (2) the east-west mortality gap has nothing to do with masks. I get the feeling that if they were forced to choose, the experts would pick (1). They’re incapable of ever publicly admitting (2) could be true.
In short, the Japanese government got 25 credentialised experts put out a document that can be easily ripped apart by a pseudonymous blogger with no background in medicine or epidemiology. I guess that sums up the current state of mask science. Interestingly, one of the 25 is Dr Satoshi Kutsuna, who really should know better. In fact, he did three years ago.
And he wasn’t the only one.
Stupid mask fantasies.
Common sense told me from jump, that those things are useless:
Gaps around edges of masks, and mask material stops virions like a chain link fence stops a gnat.
Stupid people making stupid rules.
And plenty of fools to mind them.
OMFG.
Kutsuna should quit his job and work at a supermarket. I have seen a couple of help wanted signs at a few supermarkets in my area. He doesn't have to delude himself for a paycheck. I do realize there would be a pay cut. He can of course still delude himself and others at the supermarket about food quality and expiration dates. But that would have a lesser effect on the population. I will send him an application. Not by email. By post. I imagine his email account is full with mails calling him a sell out , grifter, schmuck, putz, and the like. On the positive side, I am glad that schmucks like Kutsuna exist. One more person to the list of people we can make fun of. Making fun of people is still legal...