CD79A and COVID-19: ,11,18 While several reports suggest a modest boost in SARS-CoV-2 spike-specific mucosal IgA (hereafter referred to as mucosal spike IgA) levels following systemic SARS-CoV-2 vaccination in COVID-19 convalescents, intramuscularly delivered SARS-CoV-2 vaccines have negligeable effect on mucosal spike IgA responses in individuals naïve to the virus, where no mucosal priming has occurred.7