Re: Obligatory Covid-19 analogy
Immunity via exposure is just as prone to failure by mutation as immunity via vaccine. All a vaccine does is trigger immune responses in the body without necessarily making you sick first.
That said, the structure of COVID-19 does not lend itself well to significant rearranging, much as how measles (a notoriously stubborn virus otherwise) can't seem to find a way around our current level of vaccine tech. Influenza is much easier to rearrange, which is why we can't seem to peg down a universal vaccine for it just yet.
The catch right now is how long the immunity effect lasts. There are hints that, like common cold coronavirii, the effect may not be as long as we'd like (months versus a year or two).
Biting the hand that feeds IT
