Bacteriology". — "Studies about d'Herelle's Bacteriophagus" . By 

 J. W. Janzen and L. K. Wolff. (Coram iinieated by Prof. 

 C. Eykman). 



(Communicated at the meeting of February 25, 1922). 



I. The Bacteriophagus in Enteric Fever. 



We have succeeded in proving the existence of this bacteriophagus 

 in the faeces of patients recovering from enteric fever, as has also 

 been described by d'Herelle. 



If d'Herelle's views are right, it must be possible to influence 

 the process of enteric fever favourably by administering bacterio- 

 phagum antityphoideum. 



We have tried this in three cases and perhaps we have observed 

 a somewhat favourable result, but not a striking success. The 

 explanation hereof might be found in the fact that this bacterio- 

 phagus did not happen to be adjusted at the bacterium, that caused 

 the illness of these patients. We ha\e considered it worth while to 

 examine this systematically. 



We have been able to make use of three bacteriophagus specimen, 

 two of which were from the faeces of patients recovering from 

 enteric fever, the third from the faeces of a healthy person who 

 had had enteric fever forty years ago. We have examined the effect 

 of the bacteriophagi as opposed to 17 typhoid strains, 15 of which 

 came from the collection of the Laboratory for Hygiene, the two 

 others from the blood of patients out of which the bacteriophagus 

 had also been taken. We have steadily examined the clearing up 

 of the broth, which has turned slightly turbid by typhoid bacilli 6 

 hours old from agarcultures, the checking of the growth of typhus- 

 bacilli in broth, and finally the formation of little islands on the 

 agarplate(plages). 



What can be the cause of this difference in behaviour? 



It might be supposed that the uninfluenced typhoid strains would 

 be so called resistent strains. 



This would be possible for some strains that are not influenced 

 by any of the three bacteriophagus strains (3, 8, 20). 



But we also see that the bacteriumstrain which is influenced by 

 one bacteriophagus is not influenced by the other, and vice versa. 



