CD79A and vibrio infectious disease: O-specific polysaccharide-specific memory IgA B-cell responses have been associated with protection against cholera in orally vaccinated North Americans subsequently challenged with wild-type V. cholerae, and OSP-specific memory IgG B cell responses have been associated with protection against cholera in household contacts of cholera index patients in Bangladesh.17,19 Whether these memory B-cell isotype differences reflect difference in animal species (mouse and human) and likelihood of previous exposure (North American volunteers and Bangladeshi residents) is currently unclear.