Like ah’ said: Coronaviruses change and that is why we used to get colds again and again. Antibodies to one do not help with another and besides that they fade over time.
The vaccines work, which is why until summer of 2021 with Delta we had virtually no cases among the vaccinated, but not as well with the new variant and as antibodies faded. Boosters reversed that trend but then Omicron was different enough to evade vaccine protection as far as infections, yet the vaccinated who got infected were well protected from hospitalization and death.
So, what should the unvaccinated consider other than they are at great risk, because they are. Still, only a few of the vaccinated millions become victims of Omicron. Over 90% of hospitalizations and even higher for deaths are unvaccinated.
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