408 CHOLERA. 



distinct species or merely varieties of the same species — and 

 on the other hand, as to the means of distinguishing the cholera 

 spirillum from other species which resemble it. These questions 

 will be discussed below. 



In considering the bacteriology of cholera, it is to be borne in 

 mind that in this disease, in addition to the evidence of great 

 intestinal irritation, accompanied by profuse watery discharge, 

 and often by vomiting, there are also symptoms of general sys- 

 temic disturbance which cannot be accounted for merely by 

 the withdrawal of water and certain substances from the system. 

 Such symptoms include the profound general prostration, cramps 

 in the muscles, extreme cardiac depression, the cold and clammy 

 condition of the surface, the subnormal temperature, suppression 

 of urine, etc. These taken in their entirety are indications of a 

 general poisoning in which the circulatory and thermo-regulatory 

 mechanisms are specially involved. In some, though rare, cases 

 known as cholera sicca, general collapse occurs with remarkable 

 suddenness, and is rapidly followed by a fatal result, whilst there 

 is little or no evacuation from the bowel, though /(?j^ mortein the 

 intestine is distended with fluid contents. As the characteristic 

 organisms in cholera are found only in the intestine, the general 

 disturbances are to be regarded as the result of toxic substances 

 absorbed from the bowel. It is also to be noted that cholera is 

 a disease of which the onset and course are much more rapid 

 than is the case in most infective diseases, such as typhoid and 

 diphtheria ; and that recovery also, when it takes place, does so 

 more quickly. The two factors to be correlated to these facts 

 are (a) a rapid multiplication of organisms, {U) the production of 

 rapidly acting toxins. 



The Cholera Spirillum. — Microscopical Characters. — The 

 cholera spirilla as found in the intestines in cholera are small 

 organisms measuring about 1.5 fo 2 ytt in length, and rather less 

 than .5 in thickness. They are distinctly curved in one direc- 

 tion, hence the appearance of a comma (Fig. 138); most occur 

 singly, but some are attached in pairs and curved in opposite - 

 directions, so that an S-shape results. Longer forms are rarely 

 seen in the intestine, but in cultures in fluids, as is especially 

 well seen in hanging-drop preparations, they may grow into 

 longer spiral filaments, showing a large number of turns. If 

 film preparations be made from the intestinal contents in typical 



