[KCUOJJQJ]

I'm not sure if it's the case but maybe 60% is the possible maximum?

I hope I understand it correctly how germs spread. Is it like this?

Imagine an infected person infects 4 other persons, and the incubation period was 1 year. Probably everyone would get the germ.

But if the incubation period was 1 second, at a certain point 1 infected person would find less than 1 person who is infectable (not already infected / had an infection that is gone now / has had an immunity? / etc.).

[vnchr]

I posted elsewhere, but yes, there are thresholds for transmission when enough of population has developed immunity: https://en.wikipedia.org/wiki/Herd_immunity#Mechanics