KOCH'S COMMA SPIKILLUM, OK BACILLUS OF 

 ASIATIC CHOLEKA {SpiriUam cholerce asiatkce) 



LIQUEFIES GELATINE 



Authority.— Koch, BerUner Min. Wochenschrift, 1884, Nos. 31, 32, 32a. 



"Where Found. — In the dejecta of cholera patients, and in the fresh intestinal 

 contents of cholera corpses. In water. 



Microscopic Appearance. — Bent bacilli, frequently hanging together so as 

 to form a semicircle or the letter S. Threads also are formed which give rise to 

 very delicate and long spiral or corkscrew forms. It is very motile, and each rod 

 has a cihum attached to one end ; the cilium has generally two distinct bends, and 

 is usually from 1 to IJ time as long as the whole rod, of which it is about J to ^ 

 the width. The cilia are stained by adding to 16 c.c. of the mordant from ^ to 1 

 drop of acid (Loeffler). (See p. 56.) It forms arthrospores according to Hueppe, 

 but it possesses no form which is endowed with any considerable powers of re- 

 sistance. Numerous involution forms appear in old cultures. They stain best 

 with an aqueous solution of fuchsin. They are not coloured by Gram's method. 



Cultures. — 



GrELATiNE pLATES. — The colonics are more or less circular, and have a rough 

 irregular surface, with coarse granular contents. Under a low power they are 

 at first light, but become later more opaque in the centre and exhibit short, 

 very fine radial hairy extensions at the periphery. Liquefaction ensues, and 

 each centre is surrounded by a slight funnel-shaped depression. 



Gelatine Tdbes.— The gelatine is slowly liquefied near the surface in the 

 shape of a funnel ; the gelatine at the point of inoculation widens and gives rise 

 to an air-bubble-shaped depression, the lower part of the needle's path in the 

 depth remaining for several days visible as a thin white thread. Ultimately 

 the whole contents of the tube become fluid. 



Agab-agab. — Forms a grey-white shining expansion. 



Blood Serum. — Grows abundantly, slowly liquefying it. 



Potatoes. — It used to be asserted that it would only grow on potatoes at 

 from 30° to 40° C, when it produced a transparent light-greyish brown expansion. 

 Erannhals (see p. 23) has recently shown that this bacillus will grow on slices 

 of potato saturated with a 1 to 2 per cent, solution of sodium carbonate both at 

 16° to 18° C, as well as at the higher temperature. The bacillus is very sensitive 

 to the slightest trace of free acid, and hence its difficulty in growing on ordinary 

 potato cultures is doubtless due to the presence of acid in such. 



Bkoth. — Produces a wrinkled and much-folded pelhcle and a deposit, the 

 liquid itself remaining nearly clear. 



Milk. — Sterilised milk is rendered strongly acid, and its coagulation takes 

 place in 48 hours at 37° C. (Haan and Huysse, Centralb. f. Bakt., vol. xv., 

 1894, p. 268.) 



Eemarks. — The cultures in media containing peptone give the so-called * cholera- 

 red ' or nitrosoindol reaction, which is fully described on p. 281. It produces sulphu- 

 retted hydrogen in broth cultures (Stagnitta-Balistreri). Finkler- Prior's baciUus 

 resembles Koch's bacillus, but its mode of liquefaction is different, being much 

 more rapid and extending at once to the bottom of the needle's path in the depth, 

 whilst the colonies are smooth-rimmed. (Compare also p. 326, where its behaviour 

 in water is described.) It used to be alleged that the Finkler baciUus was 

 identified with 'cholera nostras,' but this has since been negatived by Finkler. 

 There are many comma-shaped bacilli found in water (see p. 276; see also Koch's 

 remarks on p. 278 on the detection of the cholera bacillus in water). The Comma 

 bacillus grows best at from 30° to 40° C, but below 16° 0. its growth appears to 

 cease. It is very sensitive to dry surroundings ; thus Rigler {Centralhlatt filr Bah- 

 teriologie, vol. xiii., 1893, p. 651) found that when silk threads soaked in fresh broth 

 cultures of the bacillus were simply exposed in the air the bacilli were destroyed in 

 three hours, whilst if similar threads were wrapped up in damp cloths they were still 

 alive after two days. If guinea-pigs are first dosed with tincture of opium and sodium 

 carbonate and then receive an injection of broth cultures of the bacillus in the 

 stomach, they succumb, and the bacilli are found in the intestinal contents and in the 

 mucous membrane of the intestine, and also in the lumina of Lieberkuhn's follicles. 

 Sabolotny {Centralhlatt fur Bdkteriologie, vol. xv., 1894, p. 150) states that the 

 marmot is exceedingly sensitive to this bacillus. If 0"1 to 0*2 c.c. of a one-day-old 

 broth culture grown at 37° C. is introduced subcutaneously or into the peritoneum, it 

 dies in from twelve to eighteen hours, and the bacilli are found in the blood, liver, 

 spleen, and in the peritoneal fluid. A small quantity is also fatal when introduced 

 per OS with food or liquids, previous treatment with soda and opium being unnecessary. 

 For Pfeiifer'a method of confirming cholera bacillus by animal experiment see p. 282. 

 For the action of light on this bacillus see p. 386. 



