IL2 and COVID-19: Most notably, 21/30 (70%) NCR vaccine recipients began exhibiting non-spike-specific IFN-γ (P = 0.0004) and IL-2 (P = 0.0107) T-cell responses at 6 months post-second dose without ever reporting any clinical symptoms compatible with COVID-19, testing positive for COVID-19 by PCR/RAT, or seroconverting to possess anti-N IgG or IgA antibodies (Fig. 8A; Fig. S3).