COVID-19 mRNA vaccination elicited at least comparable neutralizing antibody levels as COVID-19 convalescents in the circulation but generated considerably lower mucosal IgA and neutralizing antibody responses against SARS-CoV-2 D614G, Delta and Omicron BA.1.1 variants than those of convalescents, indicating that the overall magnitude of mucosal antibody responses is suboptimal following vaccination. The gene discussed is CD79A; the disease is COVID-19.