Caveats: study is pre-omicron, and in a population that has a higher likelyhood of previous infection (nurses). Infection followed by vaccination leads to suppo

Caveats: study is pre-omicron, and in a population that has a higher likelyhood of previous infection (nurses). Infection followed by vaccination leads to supposed "hybrid-immunity". These findings may not translate to those who did not get infected but were vaccinated