CHAPTER XXXIII. 



SPIRILLUM CHOLERA ASIATICS (KOCH ? S COMMA 

 BACILLUS OF ASIATIC CHOLERA). 



IN 1883, Koch separated a characteristically curved 

 organism from the dejecta and intestines of cholera 

 patients the so-called " comma bacillus." This he 

 declared to be absent from the stools and intestinal con- 

 tents of healthy persons and of persons suffering from 

 other affections. The organism was said to possess cer- 

 tain morphological and biological features which readily 

 distinguished it from all previously described organisms. 

 It was absent from the blood and viscera, and was found 

 only in the intestines; and in greater number, it was 

 said, the more acute the attack. Koch also demonstrated 

 an invasion of the mucosa and its glands by the comma 

 bacilli. The organisms were found in the stools on 

 staining the mucous flakes or the fluid with methylene- 

 blue or fuchsin, and sometimes alone; by means of cul- 

 tivation on gelatin they were readily separated from the 

 stools. During his stay in India, in Egypt, and at Tou- 

 lon, Koch had examined over one hundred cases, and 

 other investigators confirmed his statements. Numer- 

 ous control observations made upon other diarrhoeic de- 

 jecta and upon normal stools were negative; the comma 

 bacillus was found in choleraic material only, or in mate- 

 rial contaminated by cholera. Soon other observers, 

 however, described comma-shaped organisms of non- 



