However, an extensive single-cell transcriptomic analysis of SARS-CoV-2 specific CD4 T cells in patients with severe SARS-CoV-2 acute infection showed that polyfunctional Th1 and Th17 cell subsets were under-represented in the repertoire of SARS-CoV-2-reactive CD4 T cells as compared to influenza-reactive CD4 T cells (91). This evidence concerns the gene CD4 and influenza.