After immunostaining for CD8 and determining the semiquantitative score as describe above, further analysis revealed no significant difference in cytotoxic T lymphocyte infiltration in frontal cortex and frontal white matter between COVID-19 patients and controls neither for all ages (cortex: p = 0.574; white matter: 0.494; χ2 test) nor when analyzed for younger (cortex: p = 0.549; white matter: 0.565; χ2 test) or older age separately (cortex: p = 0.527; white matter: 0.135; χ2 test; see also Table 4). This evidence concerns the gene CD8A and COVID-19.