CD79A and vibrio infectious disease: In addition to the safety and tolerability of up to 18 g of the investigational drug (rice flour), this trial will ensure its efficacy against cholera by demonstrating the presence of oral immune response–inducing serum and saliva toxin-specific IgA antibodies, and toxin-specific secretory IgA induced in the intestinal tract, which has not been demonstrated in previous trials (Yuki et al., 2021, Yuki et al., 2022).