I've been seeing reports out of China that people often first get a mild infection, then some while (weeks?) later get a second infection - and the second one is much, much more severe. To the point that they're wearing out cremation furnaces, building additional ones, long lines at funeral homes. It... isn't good. Given the timing, I have to wonder if this is some kind of post recovery rebound effect - or the first infection cratering the immune system (T2 type 8?) to the point that reinfection is possible, and the innate immune system then over reacts.
More generally, I would expect better cross-variant protection from post-infection (AKA 'natural') immunity than that from vaccination, simply from the way random pieces of an invading virus are presented as epitopes with 'natural' as opposed to the spike proteins presented by vaccination - and the spike is the major point of variation between variants - BUT the epidemiology doesn't show this, so I've misapprehended something. Maybe just the utter complexity of how this all works.
Anyone care to tell me which way I'm being an idiot here?