The presence of major antigens, 1, 2 and 3 were determined in 30 strains of B. pertussis isolated from children with whooping-cough hospitalized at the Hospital Emílio Ribas, São Paulo Brazil. The method used was the slide-agglutination test. Tests showed that 25(83.3%) of strains were positives for factors 1, 2 and 3. Factores 1 and 3 alone were present in 3 (10%) of strains and 1 and 2 alone in 2 (6.7%).
Whooping-cough diagnosis; Bordetella pertussis; Pertussis vaccine