396 MANUAL OF BACTERIOLOGY. 



Bacteriological Diagnosis of Cholera.— V^hen cases sus- 

 pected of being cholera appear in a community, it becomes 

 a matter of the utmost importance to determine the exact 

 nature of the disease in order that it may not become epidemic. 

 One of the first occasions when bacteriological methods were 

 put into practice in the diagnosis of cholera was at the time 

 of the appearance of that disease in the port of New York in 

 1887. 



According to Koch, the diagnosis may be made in twenty- 

 four hours or less. It is important to obtain the discharges 

 from the intestines as early in the course of the disease as 

 possible, and while they are perfectly fresh. It may be neces- 

 sary, however, to examine the moist dejecta on the linen or 

 clothing, when no other material is available. 



In the first place, one of the small, partly solid particles 

 which may be found in the discharges from the intestines 

 should be smeared upon a cover-glass, fixed in the usual 

 manner, stained with one of the aniline dyes, and examined 

 with the microscope. If taken early in the disease, the comma 

 bacilli may be present in large numbers, and they are likely 

 to be arranged in parallel groups, as already described. If 

 comma-shaped bacilli are thus found, a strong probability 

 is created that the disease is Asiatic cholera. The motility of 

 the organisms can be determined by examination in the hang- 

 ing-drop. It is to be remembered that spirilla of various 

 forms are common in the normal mouth, and may appear in 

 the stools (see pages 161 and 274). 



The method of procedure recommended by Koch, Kirchner 

 and Kolle,* sent out by the German minister of medical affairs 

 to the different directors of hygienic institutes in Germany 

 for their guidance is in substance as follows: 



Microscopic examination of the stools, preferably of the 

 mucous flakes should be made by smearing the material over 



*Kolle and Wassermann Bd. III. 1903. p. 42 et seq. 



