CHOLERA-LIKE VIBRIOS 535 



cholera-like infections occur associated with the presence 

 of a cholera -like vibrio in the stools. 



It may be that the cholera vibrio, like the B. dysenteries, 

 is not a single definite organism, and that cholera may 

 be caused by any one of a group of closely allied vibrios. 

 This view is supported by Castellani and by some of 

 Greig's observations. Castellani suggested the term 

 " paracholera " to denote choleraic cases in which the 

 true F. cholerce is absent but which seem to be caused 

 by some of these cholera-like vibrios. 



The historic " El Tor vibrios " are another instance of 

 the occurrence of cholera -like vibrios. They were isolated 

 by Ruffer x from pilgrims returning from Mecca who 

 had not had, and had not been in contact with, cholera. 

 They gave positive agglutination, and absorption and the 

 Pfeiffer reaction with cholera serum, but they haemolysed 

 and did not fix cholera-immune body. Ruffer came to 

 the conclusion that they were not genuine cholera vibrios, 

 and this is the general opinion, though some observers, 

 e.g. Neufeld and Haendel, 2 consider that they are true 

 cholera vibrios. 



Cholera-like vibrios also occur in natural waters. 



The principal cholera-like vibrios isolated from natural 

 waters are those of Sanarelli from the Seine (Sanarelli), 

 Dunbar from the Elbe (Elwers), Neisser from the Spree 

 (Berolinensis), Heider from the Danube (Danubicus), and 

 one isolated by Ivanoff (Ivanoff). 



By the Pfeiffer reaction and agglutination tests, it 

 seems probable that some of these vibrios Sanarelli, 

 Bcrolinensis and Ivanoff may be derived from the 

 standard cholera vibrio. 



1 Researches on the Bacteriological Diagnosis of Cholera. Sanitary, 

 Maritime, and Quarantine Council of Egypt, Alexandria, 1907. (Also Brit. 

 Med. Journ., 1907, vol. i, p. 735.) 



2 Arbeit, a. d. kais. Gesundheitsamte, xxvi, 1907, p. 536. 



