BACTERIAL POISONS. l6l 



CHAPTER VI. 



BACTERIAL POISONS.* 



It is now generally accepted that in most, if not all of 

 the infectious diseases, the principal symptoms and lesions 

 are to be attributed to the action of poisonous substances 

 formed by the bacteria. Even in those cases where poisonous 

 substances are not demonstrable in cultures to any great extent, 

 there is reason to believe that the bacteria in such cases may, 

 nevertheless, produce poisons in the animal body. According 

 to present views the part that bacteria play can be understood 

 best by recalhng the work of the saprophytes in producing 

 fermentation and putrefaction. It has already been shown 

 that the poisoning that comes from eating decomposed meat, 

 fish or cheese usually results from poisons which bacteria have 

 elaborated in the course of their growth. In infectious diseases 

 the bacteria grow inside of the body and form their poisons in 

 it; not before their introduction into it, as -in these cases of 

 poisoning with spoiled food. If it were possible for the cells 

 of ordinary yeast to grow in the living human body and to 

 produce alcohol from the grape-sugar of the body-fluids, the 

 person so infected might be expected to suffer from alcoholic 

 intoxication as long as the infection lasted. This illustration 

 although not entirely accurate may help to make clear what does 

 happen in an infectious disease due to bacteria, where poisons 

 formed in a manner analogous to the formation of alcohol 

 produce intoxications analogous to alcoholic intoxication. 

 Certain infectious diseases afford examples of poisoning by 



* For a full consideration of this subject see Vaughan and Novy. The Cel- 

 lular Toxins. 1902. 



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