CD8A and infection: By comparing the activation profiles between the early and late stages of the immune response, we could observe that SARS-CoV-2 infection mildly increased the activation of CD8+ T cells from the third week of natural infection (Nat-early) to the early convalescence phase (EC) (from 18.3% to 24.14%) and then greatly decreased again in the late convalescence phase (LC) (5.05%).