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MANUAL OF DETERMINATIVE BACTERIOLOGY 



Fisio-Med.-Statistica in Milano, Ser. 4, 3, 

 1885, 84; Microspira comma Schroeter, in 

 Cohn, Kryptogamen Flora v. Schlesien, 

 3, 1, 1886, 168; Vibrio cholerae Neisser, 

 Arch. f. Hyg., 19, 1893, 199; Vibrio 

 cholerae asiaiicae Pfeiffer, in Fliigge, Die 

 Mikroorganismen, 2, 1896, 527; Winslow 

 et al., Jour. Bact., 5, 1920, 204; Bacillus 

 cholerae Holland, Jour. Bact., 5, 1920, 

 217; Bacillus comma Holland, ibid., 218; 

 Spirillum cholerae-asiaticae Holland, 

 ibid., 225; Vibrio cholerae-asiaticae Hol- 

 land, ibid., 226.) From Latin, comma. 



Slightly curved rods, 0.3 to 0.6 by 1.0 

 to 5.0 microns, occurring singly and in 

 spiral chains. Cells may be long, thin 

 and delicate or short and thick. May 

 lose their curved form on artificial culti- 

 vation. Motile, possessing a single 

 polar flagellum. Gram-negative. 



Gelatin colonies: Smajl, yellowish- 

 white. 



Gelatin stab : Rapid napiform lique- 

 faction. 



Agar colonies : Circular, whitish-brown, 

 moist, glistening, translucent, slightly 

 raised, entire. 



Agar slant: Brownish-gray, moist, 

 glistening. 



McConkey's medium: Good growth, 

 colonies colorless when young, soon 

 pinkish, medium becomes darker red. 



Broth: Slightly turbid, with fragile, 

 wrinkled pellicle and flocculent precipi- 

 tate. 



Peptone water: Characteristic rapid 

 growth, chiefly at surface, where after 

 6 to 9 hours, a delicate membrane is 

 formed; little turbidity, deposit appar- 

 ently derived from pellicle (Topley and 

 Wilson, Princip. Bact. and Immun., 

 2nd ed., 1936, 388). Readily isolated 

 from the surface film of 0.1 per cent 

 peptone water. 



Litmus milk : Alkaline at the top and 

 slightly acid at bottom; generally not 

 coagulated; peptonized; reduced. 



Potato : Dirty -white to yellowish, moist, 

 glistening, spreading. 



Blood serum: Abundant growth, some- 

 times slow liquefaction. 



Blood agar: The blood pigment is di- 

 gested forming a greenish zone around 

 colonies; a true soluble hemolysin is 

 not formed (the El Tor vibrio also di- 

 gests blood pigment but in addition pro- 

 duces a soluble hemolysin. Otherwise it 

 is said to be indistinguishable from the 

 typical cholera vibrio) . 



Indole is formed. 



Nitrites produced from nitrates. 



Cholera-red reaction, which depends 

 on production of indole and reduction of 

 nitrates is positive. 



Hydrogen sulfide is formed. 



Acid but not gas from glucose, fruc- 

 tose, galactose, maltose, sucrose and 

 mannitol. Slowly from glycerol. Does 

 not attack lactose, inulin or dulcitol. 



Group I of Heiberg (Classification of 

 Vibrio cholerae and Cholera-like Vibrios. 

 Copenhagen, 1935) ferments mannose 

 and sucrose but not arabinose. 



Hydrolyzes starch actively in alkaline 

 media. 



High alkali but low acid tolerance; 

 optimum pH 7.6 to 8.0; for isolation on 

 Dieudonne's medium pH 9.0 to 9.6. 



Aerobic, grows best in abundant oxy- 

 gen; under strict anaerobiosis may fail 

 to grow altogether. 



Optimum temperature 37 °C. Maxi- 

 mum 42°C. Minimum 14°C. 



Source: From intestinal contents of 

 cholera patients in Egypt and India. 



Habitat : Intestinal contents of cholera 

 patients and carriers. 



The relationships existing among the 

 cholerigenic and non-pathogenic water 

 vibrios, although studied intensively, 

 have not yet been completely defined. 

 As a working scheme, based on somatic 

 (O) and flagellar (H) antigen studies, 

 Gardner and Vankatraman (Jour. Hyg., 

 35, 1935, 262-282) suggest the following 



