THE BACTERIOPHAGE IN DISEASE 



191 



of the disease was tested against a culture as nearly constant as 

 possible, uniform especially from the point of view of the 

 resistance of the bacterium. 



For the first three curves only (figures 6, 7, and 8) the organism 

 of the patients had not been isolated (they had fevers which 

 appeared benign) and the curves of the virulence of the bacterio- 

 phage against the bacillus of the patient is, of course, lacking. 

 For these three cases the virulence of the bacteriophage against 



Day of the Disease 



FIG. 7. Louis Pi (17 years) CLINICALLY, TYPHOID FEVER 



Virulence for 



B. typhosus 



B. paratyphosus A 



B. coli 



B. paratyphosus B 

 B. dysenteriae Shiga . 



a Shiga dysentery strain, and against the paratyphoids A and B 

 are given. 

 We will select as examples cases of different severity. 



1. Mild infections 



These were cases of typhoid fever or paratyphoid fever with a 

 mild course. Clinically they were typhoid fever but the blood 

 and stool cultures were negative. The curves for these three 

 cases are given on pages 190, 191 and 192. 



