METCHNIKOFF'S SPIRILLUM 417 



that Asiatic cholera always spreads as an epidemic from places 

 in India where the disease is endemic, and that its direct cause 

 is Koch's spirillum. It is sufficient to bear in mind that choleraic 

 symptoms may be produced by other causes, and that in some 

 of such cases spirilla which have some resemblance to Koch's 

 organism may be present in the intestinal discharges, though 

 rarely in large numbers. 



A number of other spirilla have been cultivated, which are of 

 interest on account of their points of resemblance to the cholera 

 organism, though probably they produce no pathological condi- 

 tions in the human subject. 



Metchnikoff's Spirillum (vibrio Metchnikovi). This organism was ob- 

 tained by Gamaleia from an epidemic disease of fowls in Odessa, and is of 

 special interest on account of its close resemblance to the cholera organism. 

 In the natural disease, which 



especially affects young _ ^^ ^ ^ 



fowls, the animals suffer . ***%%* * 



from diarrhoea, pass into a 

 sort of stupor, sitting with Vt4T* *"> 



their feathers ruffled, and . & 



usually die within forty- M 

 eight hours. The intestines ^ 

 contain a greyish - yellow 

 fluid, sometimes slightly 

 blood-stained, in which the 

 spirilla are found. A few 

 of these spirilla may also be 

 found in the blood in the 

 younger fowls, though 

 generally absent from the 

 blood in the older. 



Morphologically the or- 

 ganism is practically identi- 

 cal with Koch's spirillum 



(Fig. 139). It is actively FIG. 139. Metchnikoflfs spirillum, both in 

 motile, and has the same curved and straight forms ; from an agar 

 staining reactions. Its culture of twenty-four hours' growth, 

 growth in peptone gelatin Stained with weak carbol-fuchsin. x 1000. 

 also closely resembles that 



of the cholera organism, though it produces liquefaction more rapidly 

 (Fig. 140, A). In gelatin plates the young colonies are, however, 

 smoother and more circular. After liquefaction occurs, some of the 

 colonies are almost identical in appearance with those of the cholera 

 vibrio, whilst others show more uniformly turbid contents. In puncture 

 cultures the growth takes place more rapidly, but in appearance 

 closely resembles that of the cholera organism a few days older. Its 

 growth in peptone solution too is closely similar, and it also gives the 

 cholera-red reaction. 



This organism can, however, be readily distinguished from the 

 cholera organism by the effects of inoculation on animals, especially on 

 pigeons and guinea-pigs. Subcutaneous inoculation of small quantities, 



27 



