In the present study, we have investigated SARS-CoV-2 antibody responses, both IgA and IgG, in a cohort of 93 patients with moderate to severe symptoms during the first 33 days of the acute phase of infection, and in a cohort of 578 subjects mostly paucisymptomatic and/or asymptomatic enrolled in a population-based seroprevalence study of the Vaud Canton in Switzerland. This evidence concerns the gene CD79A and infection.