Co-agglutination betweenB. typhosusandB. paratyphosusB

Co-agglutination between the somatic agglutinins ofB. typhosusandB. paratyphosusB occurs more frequently than between the flagellar agglutinins in the sera of typhoid and paratyphoid B fever cases. These co-agglutinins may develop early or late in the course of the disease. It is suggested that the agglutinin absorption test is capable of distinguishing whether or not true co-agglutinins have been developed to the flagellar and somatic antigens ofB. typhosusorB. paratyphosusB.