Comparison of cohort A (orange bars) and B (petrol bars) unveiled differences between vaccination and infection: vaccinated individuals showed peaks of reactivity within the mid‐region of the S1‐subunit for both, reactive CD4+ and CD8+ T cells, and at the N‐terminal region of the S1‐receptor binding domain (RBD) and S2‐subunit for reactive CD8+ T cells. Here, CD4 is linked to infection.