(Worth reading article by Naseem Nicholas Taleb, a Lebanese American mathematician statistician who writes that six serious errors in the start of pandemic led to serious consequences of loss of life and money. Bureaucrats ignored simple solutions. f.sheikh)
SIX ERRORS: 1) missing the compounding effects of masks, 2) missing the nonlinearity of the probability of infection to viral exposures, 3) missing absence of evidence (of benefits of mask wearing) for evidence of absence (of benefits of mask wearing), 4) missing the point that people do not need governments to produce facial covering: they can make their own, 5) missing the compounding effects of statistical signals, 6) ignoring the Non-Aggression Principle by pseudolibertarians (masks are also to protect others from you; it’s a multiplicative process: every person you infect will infect others).
In fact masks (and faceshields) supplemented with constraints of superspreader events can save us trillions of dollars in future lockdowns (and lawsuits) and be potentially sufficient (under adequate compliance) to stem the pandemic. Bureaucrats do not like simple solutions.
First error: missing the compounding effect
People who are good at exams (and become bureaucrats, economists, or hacks), my experience has been, are not good at understanding nonlinearities and dynamics.
The WHO, CDC and other bureaucracies initially failed to quickly realize that the benefits of masks compound, simply because two people are wearing them and you have to look at the interaction.
Let us say (to simplify) that masks reduce both transmission and reception to p. What effect on the R0(that is, the rate of spreading of the infection)?
Simply the naive approach (used by the CDC/WHO bureaucrats and other imbeciles) is to say if masks reduce the transmission probability to ¼, one would think it would then drop from, say R0= 5, to R0=1 ¼. Yuuge, but there is better.
For one should count both sides. Under our simplification, with p=1/4 we get R0′= p² R0 . The drop in R becomes 93.75%! You divide R by 16! Even with masks working at 50% we get a 75% drop in R0.