THE BACTERIOPHAGE IN DISEASE 193 



It should be noted that in these three cases in which improve- 

 ment was rapid, the curves representing the virulence of the 

 bacteriophage are comparable. It is also to be noted that in 

 all, the accessory virulences for B. dysenteriae Shiga and for B. 

 coli are very high, and that the acquisition of virulence for 

 B. typhosus and B. paratyphosus A and B is early and is maintained 

 up to the beginning of convalescence. In the case of Louis Pi. . 

 the abrupt deflection in virulence on the twenty-second day 

 preceded a slight relapse which occurred on the twenty-fifth to 

 the thirty-second day. This complication did not prove serious 

 since the virulence of the bacteriophage increased gradually 

 from the twenty-third day. 



2. Severe injections 



The three cases cited here were serious, with both stool and blood 

 cultures positive. All were infected with B. typhosus. 



1. Renee Mar. . . . (thirty-two years, fig. 9). 



The bacteriophage was from the beginning virulent for B. coli, 

 and remained so during the course of the disease, throughout 

 convalescence, and up to the time when the patient was dis- 

 charged from the hospital completely cured. It may be noted 

 that the acquisition of virulence by the bacteriophage for the 

 bacillus of the infection coincides with the first defervescence. 

 Then this virulence became reduced and the temperature again 

 went up. The infection is definitely overcome at the time when 

 this virulence is again established. 



2. Juliette Ou. . . . (thirty-six years, fig. 10). 



3. Jeanne Del. . . . (twenty years, fig. 11). 



The curves for these two cases are self-explanatory. 



8. Typhoid fever with relapse 



1. GilberteFon. . . . (four years, fig. 12). 



On the sixteenth day the disease appeared ended. However, 

 the virulence of the bacteriophage toward the bacillus of the 

 patient disappeared before the end of the crisis and the destruc- 

 tion of the pathogenic bacteria was not complete. Whereupon 

 there was a relapse, very severe, which did not show improvement 

 until the bacteriophage recuperated with a virulence sufficient 

 to control the resistance of the bacterium. 



