SPIRILLUM CHOLERA ASIATICS. 583 



the cholera toxin formed by the growth of the spirilla. 

 The larger the surface of the mucous membrane infected, 

 the more luxuriant the development of bacilli and the 

 production of toxin, the more pronounced will be the 

 poisoning, ending fatally in a toxic paralysis of the 

 circulatory and thermic centres. On the other hand, 

 however, there may be cases where, in spite of the large 

 number of cholera bacilli present in the dejecta, severe 

 symptoms of intoxication may be absent. In such cases 

 the destruction of epithelium is then either not pro- 

 duced or so slight that the toxic substance absorbed is 

 not in sufficient concentration to give rise to the algid 

 stage of the disease, or for some reason the toxin is 

 not produced to any extent by the spirilla. In no 

 stage of the disease are living cholera spirilla found in 

 the organs of the body or in the secretions. 



From this fact and other known properties of the 

 cholera bacillus, which have already been referred to, 

 several important deductions may be made with regard 

 to the mode of transmission of cholera infection. In 

 the first place the bacilli evidently leave the bodies of 

 cholera patients, chiefly in the dejections during the early 

 part of the disease (they have usually disappeared after 

 the fourth to the fourteenth day), and only these dejec- 

 tions, therefore, and objects contaminated by them, such 

 as bed and body wash, floors, vaults, soil, well-water 

 and river-water, etc., can be regarded as possible sources 

 of infection. There is a special limitation even in 

 these sources of infection, owing to the fact that this 

 spirillum is so easily destroyed by desiccation and 

 crowded out by saprophytic organisms. Thus, as a 

 rule, only fresh dejections and freshly contaminated 

 objects are liable to convey infection; after they have 



