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Data is overwhelming – lockdowns don´t work.
But, why is that? The concept, in theory, is striking – if we reduce our contacts, we reduce viral spread. This is a no-brainer, isn´t it?
But then, why is data for lockdown so bad?
An important part of the answer in this Thread
But, why is that? The concept, in theory, is striking – if we reduce our contacts, we reduce viral spread. This is a no-brainer, isn´t it?
But then, why is data for lockdown so bad?
An important part of the answer in this Thread
What is the concept behind the lockdown idea in detail?
It is based on the assumption that asymptomatic spread is a major contributor to the pandemic.
So lock up the people in their homes! This will stop asymptomatic transmission!
So far, so easy.
It is based on the assumption that asymptomatic spread is a major contributor to the pandemic.
So lock up the people in their homes! This will stop asymptomatic transmission!
So far, so easy.
BUT: most data suggest that asymptomatic transmission is not a major driver of this pandemic.
Nobody knows the exact rate, but let's assume that one asymptomatic patient transmits the virus only to 0.5 Persons, as opposed to 3 Persons when symptomatic. https://www.nature.com/articles/s41467-020-19802-w
Nobody knows the exact rate, but let's assume that one asymptomatic patient transmits the virus only to 0.5 Persons, as opposed to 3 Persons when symptomatic. https://www.nature.com/articles/s41467-020-19802-w
So the chance of an asymptomatic person #1 infecting another asymptomatic person #2 is 0.5, the chance of person #2 infecting person #3 is 0.25, and so on.
In other words, the pandemic will stop by following the most simple NPI that is not very expensive:
isolate the ill
In other words, the pandemic will stop by following the most simple NPI that is not very expensive:
isolate the ill
This is the most important, simple, but completely overlooked, and underrated NPI. Let´s call it rule #1.
Rule #1 is followed in every country, from Sweden to California, from South Dakota to Tanzania, from Cambodia to France.
Rule #1 is followed in every country, from Sweden to California, from South Dakota to Tanzania, from Cambodia to France.
Rule #1 is like a giant.
Any additional Social distancing that comes *on top* of rule #1 will only have minor or no impact, as it only applies to asymptomatic persons (or a few non-compliment individuals).
Any additional Social distancing that comes *on top* of rule #1 will only have minor or no impact, as it only applies to asymptomatic persons (or a few non-compliment individuals).
Rule #1 does not work perfectly, but additional lockdowns won´t change the course of the viral wave significantly.
Rules for healthy people simply don´t matter on an epidemiological scale.
Rules for healthy people simply don´t matter on an epidemiological scale.
Addendum: Is presymptomatic spread a major contribution? Probably not.
1. Time window for presymptomatic spread is short (Incubation -significant replication - symptoms)
2. Oligo-symptomatic individuals probably don´t spread the virus as effectively as someone with a cough.
1. Time window for presymptomatic spread is short (Incubation -significant replication - symptoms)
2. Oligo-symptomatic individuals probably don´t spread the virus as effectively as someone with a cough.
