The organism of whooping-cough has long been sought and many investigators have described it as an influenza-like bacterium. Notable among these workers was Spengler,1 who in 1897, called attention to the organism so often found in pertussis sputum. Bordet2 of Brussels has described at length his work with the bacillus of whooping-cough which hediscovered in 1905.
It appears that the organism grows by choice low in the lung and rarely above the larynx. During the early stage of the disease it is found abundantly, but becomes more scanty as the disease progresses. Its culture artificially is slow and difficult, unless the tube is inoculated without other organisms. On account of its slow growth it is easily overgrown by pneumococci and influenza bacilli. The best medium according to Bordet is defibrinated blood, human or rabbit, mixed with an equal quantity of 3 per cent. agar, containing a little extract
SILL EM. THE VACCINE TREATMENT OF WHOOPING-COUGH. Am J Dis Child. 1913;V(5):379-385. doi:10.1001/archpedi.1913.04100290038004