Enrichment medium for the isolation of Bordetella

Abstract

The development of a specimen collection and transport medium outfit for rapid laboratory diagnosis of whooping cough is described. The transport medium consisted of a semisolid agar containing charcoal, cephalexin and defibrinated horse blood. It apparently was an excellent enrichment medium for the selective isolation of B. pertussis and B. parapertussis from scantily populated specimens. The investigation of 3237 specimens that yielded 1419 positive isolates of Bordetella, including 86 B. parapertussis, during a 20 mo. period is presented. A total of 3076 specimens were processed in the laboratory by using the enrichment medium and the routine procedure. Of these specimens, 757 were submitted in the medium, from which 137 (18%) were positive. Of the 567 specimens received in Amies transport medium, 290 (51%) positive cultures were obtained by the enrichment method only and not by primary culture.