COVID-19 vaccine effectiveness against SARS-CoV-2 infection in the United States prior to the Delta and Omicron-associated surges: a retrospective cohort study of repeat blood donors
Grebe PE, Yu EA, Bravo MD, Welte A, Bruhn RL, Stone M, Green V, Williamson PC, Feldstein LR, Jones JM, Busch MP, Custer B
