Taken together, our findings show that SARS-CoV-2 specific IL-2 responses (summarised in Table 3) are sufficiently stronger in known positive cohorts, compared to unexposed controls, which would allow us to confidently identify other patients likely to have been infected with SARS-CoV-2 who lack a positive confirmatory SARS-CoV-2 RT-PCR or serological evidence of past infection. The gene discussed is IL2; the disease is infection.