86 APPLIED BACTERIOLOGY FOR NURSES 



CHOLERA 



The spirillum of cholera was discovered by Koch in 

 1884, and from its form is often called the "comma 

 bacillus." It grows well on ordinary culture-media, 

 even at room temperature, and when grown on gelatin 

 causes liquefaction of the medium. The cholera spirillum 

 can multiply in water. It is motile, does not produce 



Fig. 27. Spirillum of Asiatic cholera, from a bouillon culture three 

 weeks old, showing long spirals; X 1000 (Frankel and Pfeiffer). 



spores, and is decolorized when stained according to 

 Gram's method. 



Cholera is constantly present in India and other parts 

 of Asia, hence the name "Asiatic cholera." From time 

 to time enormous epidemics of the disease invade Europe, 

 causing thousands of deaths. 



