I am confused by the quick turn-around in the UK, here are 3 scenarios I considered and why I am not convinced by either.
a) Herd immunity reached as the last peak infected (and made immune) the remaining people. Problems: Intuitively this would have to have been very targeted infection to cause such a quick turn / high change in immunity, as we have millions, 30% population [1] (10% adults [2]), without antibodies. We had a few hundred thousand infections maybe, so I would not expect stark changes in effective R from this.
I am confused by the quick turn-around in the UK, here are 3 scenarios I considered and why I am not convinced by either.
a) Herd immunity reached as the last peak infected (and made immune) the remaining people. Problems: Intuitively this would have to have been very targeted infection to cause such a quick turn / high change in immunity, as we have millions, 30% population [1] (10% adults [2]), without antibodies. We had a few hundred thousand infections maybe, so I would not expect stark changes in effective R from this.
b) Last peak & immunity in clu... (read more)