In humans, serum and secretory IgA antibodies to antigens of B. pertussis are detected in convalescent sera and secretions, but not in sera or secretions from vaccinees. Parenterally administered vaccines, currently in use, elicit systemic but not mucosal immunity. Induction of a vigorous local immune response at the mucosal epithelium of the respiratory tract may provide superior protection against pertussis, in contrast to parenteral vaccines. Serum and respiratory (saliva and/or nasopharyngeal) samples from thirty-four symptomatic subjects with household exposure to pertussis during an outbreak in Arizona were evaluated. Assays to detect IgA and IgG antibodies against the Bordetella pertussis antigens of pertussis toxin, filamentous hemagglutinin, fimbriae, and 69K-outer membrane protein were developed and implemented. The samples were collected during an epidemiologic study by the CDC. In the future, these assays will be used for additional epidemiologic studies and vaccine efficacy trials.
