Omicron B.1.1.529 spike + CD19 + CD20 + B cells in ChAdOx1 nCoV-19 (n = 34) and GEMCOVAC-OM (n = 67) cohorts. The data are presented as median with interquartile range. Change in cytokine expression from baseline to day 29 and day 90 was assessed using a two-sided paired t -test or Wilcoxon signed-rank test based on normality. Expression at day 29 and day 90 in both the groups was compared using a two-sided t -test or Wilcoxon rank sum test based on normality.