CD79A and pertussis: To probe spectrum bias[42] in the sensitivities obtained in our 46 pertussis cases, we also calculated sensitivities in the 91 IgA and 91 IgG levels obtained in weeks 9 and 13 of the epidemic of all 50 subjects with clinical pertussis, after they had coughed for at least 1 day during their period of clinical pertussis (Table 1).