CD79A and infection: LAIV studies show weak evidence that high levels of baseline IgA may limit LAIV infection/and or virus shedding for some influenza strains [32, 50], but no link was observed in the Flushed study (Flushed: nasal flu vaccine study (publishing.service.gov.uk)) between baseline IgA levels and fold changes in systemic IgG responses post vaccination [51].