… and humans are highly heterogeneous, so until we know the statistical frequency of these re-infections, they should not alarm us any more than the occasional influenza or measles re-infections do (6/6).

— Bloom Lab (@jbloom_lab) August 28, 2020

Exactly. People are making a big deal of this and it’s probably a nothingburger. Every virus/bacteria has a certain (usually small) percentage of people that get reinfected — either because they have a poor immune system, or an abnormal one. I’d expect just from the little I know of other viruses (have read several virology textbooks in the past two decades) a reinfection rate of 0.5% or so within ~1 year.

I’d be really, really surprised if there weren’t some reinfections.