CHOLERA 135 



CHOLERA 



The diagnosis of cholera can only be made on clinical 

 grounds alone during' an epidemic, as other diseases present 

 almost identical symptoms and course. The importance of 

 making- a correct diagnosis arises less from the interests of 

 the patient than from those of the general public ; if the case 

 is one of true Asiatic cholera, the sanitary authorities must 

 be notified and the fullest precautions taken to prevent the 

 spread of the disease. In all suspicious cases a quantity of 

 the rice-water stools (in a bottle sterilized by boiling or by 

 dry heat and securely packed) should be forwarded at once 

 to a public laboratory. Meanwhile the diagnosis may be 

 established with a fair amount of certainty by the following 

 simple tests : 



1. Take a platinum loopful of the dejecta and spread it in a 

 thin film on a clean slide; dry, fix, and stain with carbol 

 fuchsin for three minutes; wash, dry, and mount. 



2. Prepare another film and stain by Gram's method. 



EXAMINATION OF THE FILMS. 



The spirillum of Asiatic cholera is about half as long as a 

 tubercle bacillus, or rather longer, and much thicker. It is 

 slightly curved : hence the name of the. "comma bacillus." It 

 looks very like a caraway seed (Plate II., Fig. 5). 



In the carbol fuchsin specimen vast numbers of these curved 

 rods will be seen; probably few other organisms, if any, will 

 be present if the case is one of true cholera. Two or more 

 rods may often be found joined together with their concavities 

 turned in opposite directions, giving- the whole the appear- 

 ance of a very elongated spiral. In the stools (but not usually 

 in cultures) the individual rods have frequently a parallel 

 arrangement, presenting the appearance of " shoals of fish 

 swimming up stream." 



If you see these appearances examine the Gram specimen. 

 Very few organisms will be visible, as the cholera vibrio does 

 not retain the stain when treated in this way. 



If vibrios having the above characters are present, proceed 

 as follows : 



Take two or three small flasks (preferably sterilized by 

 heat), and add to each 100 c.c. of water, i gramme of peptone, 

 and J gramme of common salt ; boil thoroughly, and allow to 



