Since local mucosal immunity also plays a key role as it contributes to reducing the risk of infection and amelioration of disease severity; humoral responses in saliva were evaluated in mice orally immunized with the algae-made RBD, which not only induced a similar systemic IgG response compared to the injectable vaccine containing alum, but also induced significant IgG responses in saliva and IgG and IgA in feces, suggesting the induction of a relevant immune response at both levels. Here, CD79A is linked to infection.