[I]f you believe herd immunity is only reached at 60 per cent, you should be terrified at any loosening of lockdown. If you don’t, then you must reconcile antibody testing that says 80 per cent are still susceptible with the difficulty the virus seems to encounter in marching very far past 20 percent of the population.
That is the reconciliation my hypothesis achieves. I propose that there may exist forms of human resistance to this virus that don’t show up in Covid-19 antibody tests.
[I]n focusing on that Covid antibody test alone as indicating a pass-or-fail immunity, we could be overlooking important ways in which humans may be endowed with, or acquire, other kinds of resistance.
https://www.spectator.co.uk/article/why-has-coronavirus-fled-london-