IFNA1 and COVID-19: However, to date, no study has directly compared immune responses to all 3 FDA-approved COVID-19 vaccines at single-cell multiomic resolution.METHODSWe longitudinally profiled SARS-CoV-2-naive adults (n = 31) vaccinated with BNT162b2, mRNA-1273, or Ad26.COV2.S, integrating plasma cytokines, antibody titers, and single-cell multiomic data (DOGMA-Seq).RESULTSWe discovered a distinct, transient IFN program termed ISG-dim, which emerged specifically 1-2 days after the first mRNA dose in approximately 10% of myeloid cells.