The Cholera " Comma" Bacillus. By G. F. Dowdeswell. 957 



of the civilized world, far exceeding that of any other micro- 

 organism, or indeed almost of all those previously described com- 

 bined. This is primarily a pathological or medical question, but 

 as it cannot be excluded from a description of the organism, I 

 shall now state what seems to me its present position, in as few 

 words as possible, and the more readily because the subject, which 

 has been warmly contested, appears to me to be now on its main 

 point conclusively settled by the result of recent experiments. 



As a result of his investigations in Egypt and the East 

 Indies, Dr. Koch expressed the opinion that the comma bacillus 

 which he had discovered was specific to, i. e. occurred only in, and 

 was diagnostic of, Asiatic cholera ; he also stated his belief that 

 if not the true cause, it probably stood in some relation to the 

 disease.* This opinion was based upon the fact, as he stated, that 

 the microbe which occurred invariably and in vast numbers in cer- 

 tain situations in cholera cases, was specifically distinct from all other 

 organisms of similar form which occiurred elsewhere, and also by 

 the circumstances of its distribution in the tissues of the intestine. 

 Thus the hope was general that we had obtained knowledge of the 

 utmost value on which to base the treatment for mitigating one of 

 the greatest scourges to which mankind is subject. 



As will be remembered Drs. T. Lewis and Klein were amongst 

 the first who stated their conviction that the microbe found by 

 Koch was not specific to cholera, but occurred elsewhere, and 

 notably in the saliva of some healthy persons. This opinion has 

 been fully justified, as Dr. Klein has since succeeded in obtaining 

 pure cultivations of this microbe from the saliva of his own mouth, 

 which both in their microscopical characters, and by the test in- 

 sisted on by Koch, their habit of growth in solid cultivations, are 

 in every respect identical with the so-termed cholera comma 

 baciUi. 



The views of Koch were also roughly shaken by the results of 

 the English Cholera Commission with Dr. Klein in India, with 

 respect particularly to the occurrence of this microbe in the tissues 

 in cholera cases, examined immediately upon death, on which point 

 the English was perfectly in accord with the French Cholera Com- 

 mission, viz. that this organism does not by any means invariably 

 occur in any great numbers in this situation. 



With respect to the crucial test of the relations of any microbe 

 to disease, the one so often effectively employed by Koch himself, 

 viz. inoculating animals with pure cultivations of it, although it has 

 been asserted in some instances on the Continent that choleraic 

 symptoms have been experimentally induced in animals by this 

 means, I think these may one and all be finally dismissed as incon- 

 clusive or erronoous, and we might have abided by the original and 



• DcutHch. Mc<l. Wocli., 1X8:!, \(». 12, p. (JIG. 



