Studies withH. pertussis

Abstract
The existence of separate and qualitatively distinct phases of Hemophilus pertussis as postulated by Lewlie and Gardner (1931) has been confirmed, more recent workers notwithstanding. However, evidence is presented that variation is even more complex in minor relationships than found by the former workers. Strains may be found which although representative of a given phase in most respects, may differ in some. Data pertaining to the cross agglutinative characteristics of the various phases of H. pertussis with Bacillus parapertussis and Brucella bronchiseptica are presented. Evidence is presented which suggests that Phase I organisms are not simply Phase III organisms with a Phase I surface coating, but are antigenically different in their entirety. Little Phase III and virtually no Phase IV agglutinogen is contained within Phase I organisms. Master strains of broad specificity maintained in stabilized desiccated form are suggested for use in production of vaccines for whooping cough.