This is completely untested but i would assume that the more times you get infected or vaccinated, the more resistance you get to subsequent infections. The alternative is that covid variants keep reinfecting people over and over and people who just barely make it out of the hospital come back, which is <i>really</i> bleak.<p>So Omicron is reinfecting people but it’s not as severe, not only because of specific mutations, but because most people have already been infected / vaccinated multiple times.<p>This would also apply to other diseases. So if someone has been infected with e.g. the flu 5 times, it debunks this theory. IIRC there are multiple common colds which would explain why some people get sick with cold almost every year (and even then infections tend to be spread out). Anecdotally there was one time i was infected with some sort of stomach bug 4 times in a short span, but i’ve never had a stomach bug since then.