NATURE 



97 



THURSDAY, DECEMBER 3. 18S5 



THE ETIOLOGY OF CHOLERA 



THE announcement by Dr. Koch, as chief of the 

 German Cholera Commission, that he had dis- 

 covered a micro-organism which was not only pecuhar 

 to cholera, but which had a causal relation to that 

 disease, was all along felt by many to have been made on 

 insufficient evidence, and in consequence the India Office 

 in 18S4 appointed Drs. Klein and Heneage Gibbes to 

 visit Bombay, Calcutta, and other Indian cities, with a 

 view of studying the disease from the micro-pathological 

 point of view. Their report was received early this year, 

 and whilst it supported Koch's statements to the effect 

 that choleraic dejections were generally characterised by 

 the presence of the comma-shaped bacilli which had been 

 described, it distinctly denied many of the asser- 

 tions which had been made by that observer, and 

 it altogether set aside the notion that the comma- 

 bacillus bore any causative relation to the disease. The 

 point at issue was felt to be of such importance that the 

 India Office somewhat recently appointed a Committee 

 of physicians to consider the report made by Klein and 

 Gibbes, and to advise them on the matter. 



The Committee in question do not profess to have 

 done more than to study the subject as it has been dealt 

 with in the several reports issued by Koch, Klein, and 

 Gibbes, and to communicate their views of the merits of 

 the several reports to the India Office. They deal with 

 the contentions of Koch under several headings. Thus, 

 in the first place, they refer to his assertion that the 

 number of comma-shaped organisms in the intestinal 

 tissues and contents is in proportion to the acuteness of 

 the attack, and that these organisms generate within 

 the body a ferment by which the system is poisoned. 



As to this, it is admitted by Klein and Gibbes that if all 

 that Koch asserts on this point were correct there would 

 be strong grounds for believing that the comma-bacilli 

 must in some way or other be related to the cholera pro- 

 cesses ; but their observations are in direct opposition to 

 the assertion made. As regards the intestinal tissues, and 

 notably the mucous membrane, it was found that, in some 

 most acute cases in which the post-mortem examination 

 was conducted as soon as possible — at times in a quarter 

 of an hour — after death, the comma-bacilli were only con- 

 spicuous by their absence ; and that these organisms were 

 only present in dead tissues, including the mucus flakes. 

 Indeed, it is contended that the comma-bacilli are only 

 putrefactive organisms ; and the Committee, having these 

 facts before them, express the opinion that no direct 

 relation exists between the number of comma-shaped 

 organisms and the gravity of the attack. 



Another of Koch's contentions is to the effect that the 

 comma-bacilli are not found except in connection with 

 cholera. Now Klein and Gibbes maintain that these 

 bacilli, or some that in morphological respects appear like 

 them, are found in diarrhoea stools, that they have been 

 met with in cases of dysentery and enteric catarrh, and 

 that in other cases they have been found, together with 

 certain putrefactive organisms, in as large numbers as in 

 many cholera stools. And further, Klein has, since the 

 Vol. xxxni. — No. 840 



issue of his report, found that by ligaturing a portion of 

 the bowel of a monkey, large numbers of comma-bacilli 

 were produced, and that these have been found, after cul- 

 tivation, to present the same character as the so-called 

 cholera bacilli. Besides which, Klein has found comma- 

 bacilli, similar in appearance to those found in cholera, 

 to be ordinarily present in various parts of the alimentary 

 tract in health, and as regards some taken from the 

 mouth, he has succeeded in cultivating them, and in de- 

 monstrating that their action on the media in which they 

 grow is identical with that of the bacilli found in cases of 

 cholera. And the Committee, whilst not convinced that 

 the absolute identity of the two sets of bacilli has been 

 proved, are inclined to agree with Klein's contention. 



The third point examined is Koch's statement that the 

 presence of comma-bacilli in a tank which supplied cer- 

 tain cholera-affected villages in Calcutta with water was, 

 practically, a proof of the causal connection between the 

 organisms and the disease. As to this, Klein and Gibbes 

 report that they, too, examined the water from this tank, 

 and that it revealed undoubted comma-bacilli in every 

 respect identical with those found in choleraic dejecta ; 

 they further added that the water had been contaminated 

 with choleraic evacuations, and that, notwithstanding 

 these two conditions, its extensive use by many human 

 beings had not been followed by a single case of cholera. 

 The reporters hence submit that the water did not con- 

 tain the cholera virus, and that this latter has nothing to do 

 with the comma-bacilli. Similar evidence as to other tanks 

 is also adduced, and it is added that these tank-commas, 

 having been cultivated, are found to be identical with 

 Koch's comma-bacilli. The question as to the existence 

 of any causal connection between comma-bacilli and 

 disease in animals as the result of inoculations is also 

 discussed, and it is regarded as demonstrated that neither 

 the alvine dejections of cholera nor cultivations of isolated 

 comma-bacilli obtained from such dejecta are capable of 

 producing cholera, nor indeed any disease resembling it. 



The Committee, therefore, have concluded that, though 

 comma-shaped organisms are ordinarily present in the 

 dejections of cholera patients, they are not found in the 

 blood or in any of the tissues, even when these are 

 examined in a recent condition ; that comma-shaped 

 organisms of closely allied morphological appearance are 

 ordinarily present in different parts of the alimentary 

 canal in health, and can be developed there to an unusual 

 extent in diseases characterised by hyper-secretion of the 

 intestine ; and that there is no evidence to show that the 

 comma-shaped bacilli found in cholera induce that disease 

 in lower animals or in man. 



According to the Committee, we are now much in the 

 same position as we were before Koch's experiments were 

 instituted, in so far as the prevention of cholera is con- 

 cerned ; and Dr. Timothy Lewis, the Secretary to the 

 Committee, and who has had a wide Indian experience in 

 connection with the micro-pathological study of the disease, 

 further points out that there is nothing new in Koch's 

 observations except in so far as an ingenious and beautiful 

 process facilitating the investigation of micro-fungi is 

 concerned. Dr. Lewis asserts, indeed, that he had mad" 

 hundreds of cultivations of the bacilli in question, ana 

 that he had long since arrived at the conclusion that they 

 were identical with some of the minute vibrios which ha\ 



