In early research, Mathew et al. defined three immune types of hospitalized COVID‐19 patients1: those with strong CD4+ T‐cell activation and proliferation, positively correlating with disease severity2; those with weak CD8+ T‐cell, CD4+ T‐cell, and memory B‐cell responses, not relating to disease severity; and3 those lacking detectable lymphocyte responses, negatively associating with disease severity.18 This evidence concerns the gene CD4 and COVID-19.