SPIRILLUM CHOLERZ ASIATICZ. 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 he 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 
