Terminal effector (CCR7-CD45RA-CD45RO+CD27-) cells were decreased in T2DM patients with Covid-19 as compared to healthy controls, corroborating with the observation that these cells are first to react with the virus and the subsequent pro-inflammatory cytokine milieu is responsible for the apoptosis of these cells. The gene discussed is CD27; the disease is type 2 diabetes mellitus.