A study was done testing samples pulled from ~1.5 million blood donations in the US looking for Covid antibodies. >By May 2021, the combined infection- and vac

A study was done testing samples pulled from ~1.5 million blood donations in the US looking for Covid antibodies. >By May 2021, the combined infection- and vaccination-induced seroprevalence estimate increased to 83.3% (95% CI, 82.9%-83.7%) https://jamanetwork.com/journals/jama/fullarticle/2784013 https://jamanetwork.com/journals/jama/fullarticle/2784013 The delta variant surge didn't hit the States until after this study concluded, so one would expect the numbers to be quite a bit higher today.