The duration of the acute phase of COVID-19 also correlated with the SI of the double-positive IFNg+IL-2+ ELISpot assay (R2 linear = 0.170, cc = 0.265, p = 0.027), with significantly more double-positive T-cells at the 12-month follow-up in participants with a longer versus shorter acute phase of COVID-19 (12/31 (39%) vs. 3/39 (8%); p = 0.002). The gene discussed is IL2; the disease is COVID-19.