A study published today in Nature shows T-cell activation is present in all individuals even seventeen years after SARS-CoV infection.
It seems increasingly doubtful people will need more than one shot of the vaccine or one infection, even after sterilizing immunity is gone after a year or so (which some people naïvely confound with immunity as a whole as evidenced... here and there).
Then it'll just be another common cold if it's still symptomatic at all (which maybe it won't be, since cellular immune cross-reaction to other coronaviruses seem to be able to effectively purge SARS-CoV-2 with mild to no symptoms already).
Edit - as a side note, I'm convinced there must be some reaaally massive immune cross reaction with other or others, as of yet unidentified, betacoronavirus(es) in eastern and specially southeastern Asia. Cultural differences and mask wearing in no way can be responsible for the difference force of infection we're seeing between various places in the world, given the H1N1 experience.
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