35 



Rosenow (Rochester), whose investigations covered i . wives" 

 of the pandemic. Only at the beginning of the first epidemic 

 was Pfeiffer's bacillus cultivated in large quantities from influenza 

 sputum; laler it was hardly found at all. The medium was con- 

 tinually controlled by the inoculation of a pure culture. Altogether 

 the microbe was found in 13 o/ of 571 samples of sputum, and 

 in the lungs of 5o/ of 107 post mortem examinations. 



Dick & Murray (Chicago) examined the relations of Pfeiffer's 

 bacillus during the decline of the influenza from Oct. 1918 to Jan 

 1919. In patients with influenza symptoms it was found in these 

 4 months respectively in 74, 54, 43 and 36o/ of the cases. Simul- 

 taneously Pneumococcus increased in extent. 



All these various investigations during the pandemic give 

 us the impression that there were marked differences in the 

 distribution of Pfeiffer's bacillus at different times and in dif- 

 ferent localities. 



A very large proportion of the investigations undertaken 

 immediately after the beginning of the pandemic yielded either 

 absolutely negative results, or the bacillus could only be found 

 in a few r cases. This state of affairs was particularly noti- 

 ceable in Germany. 



In many cases the negative result was undoubtedly due to 

 defective technique. Park cites several instances of experien- 

 ced investigators being able to demonstrate Pfeiffer's bacillus 

 in large numbers in the same hospitals where others had failed 

 to find it. 



This is however not sufficient to explain all the negative 

 findings. 



Mandelraum (Munich) examined a large number of samples 

 of influenza sputum in June and July 1918 without being able to 

 find Pfeiffer's bacillus either microscopically or by cultivation. One 

 of the dyes used for staining the preparations was dilute fuchsin 

 solution. Similar negative results, both microscopically and by cul- 

 tivation, were obtained in his examinations of the „whole bronchial 

 tract" in numerous autopsies. That the negative results were not 

 due. to lack of experience in the demonstration of Pfeiffer's ba- 

 cillus is evident from the fact that Mandelraum had often cultivated 

 it from bronchopneumonia in children who had died from measles, 

 in the last few years before the pandemic. 



Selter (Konigsberg) (2,3), who had also previously had expe- 

 rience in detecting Pfeiffer's bacillus, could only find it once in 

 over 100 cases either microscopically or culturally, although the cul- 

 tures were made 2—3 hours after the samples were taken from 



3* 



