So back in Dec I posted THIS.
I made a note to try to remember to check for more info in a few months, to see if they, or anyone, followed up on it. I almost forgot, but then a couple days ago I ran across THIS.
SARS-CoV-2, MMR and Tdap antigen-experienced T cells share identical TCRs.
T cells with shared TCRs have features of TEMRA, a memory anti-viral T cell subset.
Prior MMR or Tdap vaccination correlates with reduced COVID-19 disease severity.
Now yes, correlation isn’t causation and all that. But I really hope they continue to look into this. Among other things its going to be a WHOLE lot easier to convince skeptical people to get an MMR or Tdap booster than it is a whole new vax that they don’t trust.