> How long immunity lasts for following covid-19 infection is the biggest unknown. Comparison with other Coronaviridae suggests it may be relatively short-lived (i.e. months). Anyone have sources for this? I've been skeptical of the rumors about reinfection, because they seem to be based on tests coming back positive after recovery, but the tests are rt-PCR based, and your body will be shedding leftover bits of RNA a…
This variant of CV is fairly infectious and makes some people very ill. It also kills a non-trivial percentage.
So the worst case is an incredibly dangerous virus that mutates every season. We'd have to get used to taking extreme measures, or losing around 1% of the population every year.
But the usual trend is for viruses to mutate in a less dangerous direction. And immunity isn't binary. It's more like molecular pattern matching with variable memory. So the population as a whole wouldn't be starting from scratch every season - any more than it does with colds or flu, even though they both mutate quickly.
Short term we're likely to have the equivalent of a few years of very bad flu seasons, and longer term that would settle down to a less dangerous cycle - still lethal for some people, but not a perpetual state of danger and crisis.