Mr. Luddite wrote:

The jury is still out on the idea of "herd immunity" ... or any
immunity at all with covid-19.

"WHO warns there's no evidence of coronavirus immunity as global death
toll reaches 200,000"


https://www.yahoo.com/news/warns-theres-no-evidence-coronavirus-111626171.html


It appears to me, that they are lacking any large research in to the
immunity side. A few small,scale studies, like Stanford in the Silicon
Valley, but we are testing for sick people not recovered people. Maybe
hard to switch from healthcare for the sick to research on recovered to see
if there is an acquired immunity.