A COMMON MICROBE MAY BE PATHOGENIC 263 



A COMMON MICROBE MAY BE PATHOGENIC 



The septic vibrio, we have said, occurs everywhere. 

 Almost always there are billions of them in the intes- 

 tinal canal of all animals. We invariably find them 

 in the soil, and, from studies on the etiology of anthrax, 

 which we shall meet again shortly, Pasteur was con- 

 vinced that the chances were very great that a guinea 

 pig or a rabbit inoculated with drainage water from 

 any soil whatsoever would die of septicemia. l 



Here, therefore, we have a very common organism, 

 which we discover to be very dangerous and capable 

 of causing a deadly malady when it enters the tissues 

 through a wound. Why this penetration of the tissues 

 does not occur more often and why the malady induced 

 thereby is not inscribed on the list of prevalent diseases 

 was an embarrassing question, and one with which the 

 partisans of the theory of the spontaneous generation 

 of disease should have triumphed. "You see clearly," 

 they might have said, "that something more than the 

 microbe is needed to make us ill, since in this case we 

 so often find the organism and so rarely the disease." 

 Pasteur knew well that he laid himself open to attack, 

 since this theory would not be easily accepted, that a 

 common organism could become pathogenic under 

 certain conditions and at certain times, and it was for 

 this reason that at the end of his Note to the Academy 

 of Medicine he gathered together examples and proofs 

 of this fact. This Note, which seems a little disconnected, 

 is unified only when it is regarded in this light. 



1 Examinations made during the late German war, in which gas gan- 

 grene very commonly followed neglected wounds, indicate that this 

 organism or one acting like it occurs in practically every gram of soil in 

 Northern France and Belgium. TVs. 



