Similar to surviving H7N9 patients (Fig. 2f), patients hospitalized with seasonal influenza (A/H1N1, A/H3N2, and B strains) had high CD38+PD-1+ expression early after infection, followed by a decrease with recovery (p = 0.04, standard two-tail Student’s t-test ; Fig. 2i). This evidence concerns the gene CD38 and infection.