
The Tricky Math of Herd Immunity for Covid-19 - lnyan
https://www.quantamagazine.org/the-tricky-math-of-covid-19-herd-immunity-20200630/
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vmurthy
My mind goes back to Sweden really. It was a sort of (unintended) natural
experiment which seems to have gone wrong. In hindsight, the devil (of herd
immunity) in details is really an eye-opener for many public health officials
I guess. AFAIK, there is still no confirmed research on :

* What percentage of people are supposed to develop antibodies to be classified as immune? Per the article, this can widely vary

* Even if someone develops antibodies, how long it will last

Without these two data points, Sweden's decisions really seem disastrous but
hopefully some good comes out of this :(

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collyw
They aren't doing as badly as a number of other countries and never needed a
lockdown. I would call that a relative success.

Looking ta their graphs is interesting, they seem to be having a second wave
in terms of new cases, but seem to have peaked with deaths.

[https://www.worldometers.info/coronavirus/country/sweden/](https://www.worldometers.info/coronavirus/country/sweden/)

Regarding antibodies, the original SARS (which is the closest related virus)
antibodies lasted around 3 years on average, with some people testing positive
17 years later. Doctors are expecting this to be similar, but time will tell.

