PRESERVATION OF CHOLERA STOOL SPECIMENS FOR 

 DELAYED BACTERIOLOGIC EXAMINATION l 



By C. S. Panganiban and Otto Schobl 



(From the Serum Section of the Biological Laboratory, Bureau of Science, 



Manila) 



The importance of bacteriologic diagnosis of Asiatic cholera 

 is generally appreciated by practical sanitarians. Its importance 

 increased considerably since it became generally known that by 

 means of bacteriological examination of faeces the detection of 

 cholera carriers could be made possible. As reliable as the 

 laboratory procedure is to detect the cholera vibrios when present 

 in the faeces even in small numbers, the rapid disappearance of 

 cholera vibrios in the faeces exposed to higher temperature 

 particularly in presence of other intestinal bacteria is no doubt 

 responsible for the failures in delayed examinations. It would, 

 therefore, be of some value if a method could be devised to 

 preserve the specimen for such a length of time as is necessary 

 to transport it from the source to a laboratory equipped for 

 bacteriological diagnosis of cholera. 



Several ways suggest themselves from previous experiences of 

 others and our own. 



1. The method of preserving faeces with glycerin suggested 

 by Teague 2 for delayed examination of typhoid stools. 



2. Sodium chloride solution. It was found in previous re- 

 searches concerning the survival of cholera vibrios in water that 

 cholera vibrios remain alive in sea water for a considerable length 

 of time — in our particular experiment, between 106 and 120 

 days. :i This experience could be probably made use of. 



3. Bile. This medium, first recommended by Otolenghi, 

 possesses selective properties of high degree with regard to 

 cholera vibrios. Cholera vibrios in pure culture survive in bile 

 for an indefinite length of time. This fact was referred to 

 briefly in a previous communication + and has been utilized 



1 Received for publication February 21, 1918. 



'Teague, Oscar, and Clurman, A. W., Journ Inf. Dis. (1916), 18. 



■'Schobl, Otto, Phil. Journ. Sci., Sec. B. (1914), 9, 479. 



4 Idem, Journ. Inf. Dis. (1916), 18, 307. 



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