BEHAVIOR OF BACTERIOPHAGE IN EPIDEMICS 



501 



From this it appears that the intestinal bacteriophage is endowed 

 with virulence for the bacterium of barbone in all the buffaloes which 

 the disease had spared. 



In the course of different trips across Indo-China, I collected forty- 

 one specimens of feces from buffaloes, each specimen collected in a dif- 

 ferent village in which no buffaloes had died of barbone for at least two 

 years. In only three of these specimens could a bacteriophage active 

 for the bacterium of barbone be demonstrated, and in these cases it was 



Ngau 1 



Ngau 2 



Ngau 3 



De 



Doi 1 



Doi 2 



Lanh 



Tran 



The 



H. V. Chanh 



Hien 



Du 



Sam 



P. V. Chanh 



Cu 



So 



No 



Phuc 



Gia 



Man 



MOBTALITT 



NUMBER 



OF ANIMALS 



WHICH 



RESISTED 



10 



VIRULENCE 

 OF THE 



BACTERIO- 

 PHAGE 



+ + 



+ 



+ + + 



+ 



+ + + + 



+ + + 



+ + 



+ + + + 



+ + + + 



+ + + + 



+ + + + 



+ 



+ + 



+ + + + 



+ + + 



+ + 



+ + + 



+ + + + 



+ + + 



+ + 



weak (+). Nevertheless, the intestinal bacteriophage was present in 

 all ; but although it was active for one or another of the intestinal organ- 

 isms, its virulence was weak or lacking for the bacterium of barbone. 



We will see later, on the contrary, that in a contaminated area at the 

 time when the epizootic dies out, the intestinal bacteriophage of all of 

 the buffaloes which escaped the disease is virulent for the bacterium, 

 the causative agent of the epizootic. \Ve find here, then, the same facts 

 as were observed in the study of avian typhosis; that the protection of 

 the body in the case of barbone, a septicemic disease, is assured by the 

 bacteriophage. 



