In the IC group, the highest titres of IgA were detected after combined (hybrid) activation of the immune system (GMThyb = 2672, 95% CI: 566-12623), followed by the levels of vaccine-induced IgA (GMPvac = 275, 95% CI: 97-777), and lowest levels were observed after infection (GMTinf = 60, 95% CI: 13-280). Here, CD79A is linked to infection.