UBIQUITY OF BACTERIOPHAGE 423 



In 1 person: 



B. dysenteriae Shiga + + 



B. typhosus (3 of 4 strains tested) + + 



In 1 person: 

 B. dysenteriae Shiga + 

 B. paratyphosiis A (4 of 4 strains tested) + 



In 4 persons : 



B. dysenteriae Shiga + + 



It is needless to introduce more data bearing on this point. That 

 the bacteriophage may be present in the normal intestinal tract is vir- 

 tually accepted by everyone, but a great many seem to think that its 

 presence there is accidental. Such an opinion can be based only upon 

 investigations carried out by an inadequate technic. I repeat: in every 

 intestine there is a race of the bacteriophage protobe maintaining itself 

 there because of a symbiosis with B. coli* 



One question comes immediately to mind; When does this intestinal 

 bacteriophage arrive? Does it exist in the fetus, or is it implanted after 

 birth? And if the latter is true, when? 



We know that the intestinal contents of the fetus are sterile, the 

 normal meconium is free of organisms at the time of birth. This phase 

 of sterility is promptly followed by a phase of increasing contamination, 

 which begins, within the first few hours after birth, as a result of the first 

 deglutitive movements which carry a varied flora into the digestive 

 tract of the infant. At first there is a predominance of Staphylococcus 

 albus and of B. coli, with some of the anaerobes, and the body reacts by 

 a desquamation of the epithelium of the digestive tube. 



At about the fourth day for the breast-fed infant, somewhat later and 

 in an incomplete manner for those fed artificially, the flora is trans- 

 formed. The anaerobes, B. bifidus in particular, replace the earHer 

 flora. With the breast-fed infant the bacterial content is almost en- 

 tirely made up of B. bifidus. 



In connection with his thesis, Vedrenne"^" made a study of the bac- 

 teriophage in infancy. He was unable to demonstrate the presence of a 

 bacteriophage virulent for B. coli, B. dysenteriae Hiss, Staphylococcus 



* Upon several occasions I have remarked that the symbiosis is always due 

 to a parasitism of the one or the other of the two antagonists. All symbioses 

 which occur naturally are comparable to that which exists between a leper and the 

 bacillus of Hansen. The old concept of an association between two organisms 

 for the purpose of a common benefit is false and is never observed in nature, as 

 has been shown by Noel Bernard. 



