Specifically, geometric means of mucosal anti-spike IgG, IgA, and SIgA were 59-fold, 24-fold, and 12.8-fold higher, respectively, in the PURIFY-OBS-1 cohort of individuals with severe COVID-19, and geometric means of mucosal anti-N IgG, IgA, and SIgA were 216-fold, 44-fold, and 13.3-fold higher. This evidence concerns the gene CD79A and COVID-19.