The Tyranny of Keeping R Below 1

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THE TYRANNY OF "KEEPING R BELOW 1"


UK PM and Health Secretary have commented that the goal is to bring R below 1 & keep it there until a vaccine.


A Sisyphean task.


Impossible.


Not due to the virus, but due to a misunderstanding of logic, science & maths.


Infections rising: R > 1


Infections falling: R < 1


This would seem simple. As the epidemic grows R is above 1. As it wanes, R is below 1.


But infections cannot fall forever.


When the level of infections has fallen to very low levels (or even zero) & a large proportion of the infections detected are false positives, then the infection figures will appear fairly stable; albeit with some noise, which is a problem at lower numbers.


Since infections are stable, even if this is because they are mostly gone, R cannot remain below 1.


R will therefore rise from below 1 to 1.


& there it will remain, with some movement due to noise.


Indefinitely.


To demand that R remains below 1 is to make success impossible.







[analysis, thoughts, opinions & errors my own]

@RuminatorDan

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