NATURE 



2 37 



THURSDAY, JULY 10, 1884 



THE CHOLERA GERM 

 \ T the present moment when the Continent has again 

 1 »• become the battle-field between cholera and the 

 human race, all questions concerning the cause, diffusion, 

 and prevention of the cholera virus must take a prominent 

 place in the deliberations on the best sanitary measures 

 to be adopted in combating this insidious foe. Almost 

 all practical preventive measures in this country and on 

 the Continent as regards cholera and other infectious 

 maladies are based on the assumption — supported by a 

 good deal of evidence both theoretical and practical — that 

 the virus is particulate, and, as indicated by its self-multipli- 

 cation within the affected person, is a living organism. But 

 the nature of this supposed organism of cholera has, until 

 quite 'recently, been altogether mysterious. As is well 

 known, Prof. Koch and colleagues, sent out last year by 

 the German Government to investigate the cholera in 

 Egypt and India, have ascertained that in the rice-water 

 stools voided by patients suffering from the disease 

 there are present, besides micrococci and bacilli common 

 to the evacuations of other than cholera patients, pecu- 

 liar curved bacteria, so-called " comma-shaped " bacilli, 

 which Koch has not been able to discover in any 

 cases of diarrhoea. These " comma-shaped " bacilli Koch 

 has succeeded in isolating by artificial culture. Unfor- 

 tunately cholera has hitherto not been found transmissible 

 to the lower animals, and therefore the function of these 

 " comma-shaped " bacilli must at present remain unknown. 

 All we can therefore say is that Koch has shown that 

 in cholera evacuations there exist, besides micrococci and 

 straight bacilli, other organisms also characterised by this 

 — that they are curved or comma-shaped. Whatever else 

 has been said by Koch, his followers, and critics, scientific 

 and daily papers, as to these " comma shaped " bacilli 

 being the cause of cholera, is simply and purely a suppo- 

 sition, which, as we shall presently show, is wanting in 

 the most essential elements. 



First and foremost, Koch has been unable to find 

 anything of this " comma-shaped " bacillus in the 

 blood or tissues in any stage of cholera. Now all ex- 

 perience on cholera teaches that, whatever its cause 

 may be, the alimentary canal is not the only passage 

 through which the cholera-poison enters the system, 

 but that its entrance through the respiratory organs 

 is also an established fact. For this reason it is neces- 

 sary to assume that, as in other infectious diseases, it 

 passes in the stage of incubation of the disease through 

 the blood and system. The symptoms of cholera, the 

 whole nature of the disease, shows that it is not a local 

 distemper of the alimentary canal, but that the latter is 

 merely a symptom of the malady, as much as in typhoid 

 fever the distemper of the ileum and spleen, or in scarla- 

 tina that of the skin, throat, and kidney. Had Koch 

 found the "comma-shaped" bacillus in the blood or the 

 tissues, e.g. the blood-vessels of the alimentary canal, 

 mesenteric glands and spleen, the nature of this "comma- 

 shaped " bacillus would have been as obscure as ever, but 

 still there would have been some sure element in the chain 

 Vol. xxx. — No. 767 



of surmises. Of course it might be argued, and as a 

 matter of fact it is argued by Koch in the reports to his 

 Government, that the bacillus, having found entrance into 

 the cavity of the intestines, there multiplies, and produces 

 some ferment, which, absorbed into the system, sets up 

 the whole chain of appearances constituting the symptoms 

 of cholera. This is quite possible, and to a certain limited 

 extent is borne out by experience, notably in the case of 

 putrid or pysemic poisoning, where, owing to the presence 

 of putrefaction in a wound, the products of putrefaction — 

 the sepsin — absorbed in sufficient quantities into the 

 system, create the above disease, often terminating fatally. 

 In this case no specific organisms are detected in the 

 blood or tissues ; their presence is limited to the wound 

 only, and their effect is merely this, that some ferment — 

 ptomaine or some other substance — produced by them is 

 absorbed into the system. 



That this should also be the case in cholera is, as we 

 just said, possible, but it is not probable, for the simple 

 reason that the cholera virus in a large percentage of 

 cases enters the system by the respiratory organs, and 

 therefore it must be assumed in these instances to pass 

 into the general circulation, and consequently, if it is 

 to be identified, must be identified in the blood or 

 tissues. 



The practical consequences of an assumption that the 

 cholera-virus passes into the system exclusively by the 

 alimentary canal, and that it has its breeding-ground in 

 the latter only, are so great, that before acting on such an 

 assumption the basis for it ought to be established, which 

 it certainly is not. 



Secondly, is it a well-established fact that this " comma- 

 shaped " bacillus is present only in cholera evacuations ? 

 If it should be found that this bacillus is absent from the 

 alimentary canal in all other diseases, then we could at 

 best recognise it as pathognomonic, but it by no means 

 follows that it is also pathogenetic. 



I have lately had the opportunity of inspecting this 

 " comma-shaped " bacillus in specimens prepared by 

 Koch, from the rice-water evacuations, and also in artificial 

 cultures, and I have fully convinced myself of its reality. 

 But I possess prepared specimens of evacuations of 

 patients suffering from severe diarrhoea (in an epidemic 

 outbreak of diarrhoea in adults in Cornwall in the autumn 

 of 1883, and investigated by Dr. Ballard, Inspector to the 

 Local Government Board), in which specimens, besides 

 micrococci and straight bacilli, there are undoubtedly 

 present bacteria which, in shape and size and mode of 

 staining, so closely resemble the " comma-shaped " bacilli 

 of cholera that I am unable to discover a difference 

 between them. I have, however, not made any artificial 

 cultivation of them, and therefore cannot say whether 

 there exist any differences between the two, notably as 

 regards their mode of growth. 



Here is one other point to which we wish to draw 

 attention: as Cohn {Bei/riige zur Biologic der Pfian- 

 gen, Heft ii.) has shown, and as is now generally 

 accepted, a rod bacterium which is characterised by being 

 curved is regarded not as a bacillus but as a Vibrio ; 

 and it is not quite clear why, unless for the sake of 

 novelty, Koch, generally accepting Cohn's terminology, 

 j should in the case of the cholera bacterium have deviated 

 from it, and should not rather have spoken of it as a 



