Thread by @TracyBethHoeg

Many suggest "hybrid immunity" (hx of infection + vax) is superior to immunity from infection alone, but we now have 2 large studies not detecting additional benefit of vax after infection for prevention of hospitalization.
This best was just published 👇:
acpjournals.org/doi/10.7326/M2…

This Israeli study is very large & well done bc of their case-control design which matched vax'ed & controls for age, sex, socioec status status, comorbidities & exposure period. They found 1 dose of vax atfter infection offers no detectable additional benefit vs hospitalization

The second from MMWR is here finding the hospitalization rate among previously infected plus vaccinated was not lower than those who were previously infected but unvaccinated.
Figure on the right from @PeterAttiaMD

cdc.gov/mmwr/volumes/7…

So what does this mean? *Most* people who've been infected have, at least thus far, a robust immune response that protects them from severe disease & adding mRNA vax may boost their antibodies/postpone infection but won't appreciably lower their already low risk of severe disease

We don't have the research to back this yet, but it may be we end up leaning children and young adults especially will not benefit from vax on top of infection based immunity against severe disease but older, more frail adults or certain very high risk *will* benefit.

Based on these 2 studies above, I just think we need to be clearer that most adults will not gain any additional benefit from the vax against severe disease (& only transient against infection) after they have recovered from infection.

So mandating vax after recovery from infection in *most adults* really does not make sense from the standpoint of preventing severe disease or hospitalization either. And we have covered previously here that the benefit against infection & transmission is fleeting