FAMILY VII. SPIRILLACEAE 



233 



Cholera group of vibrios. 

 (Biochemically similar. Common H antigen.) 



0-sub-group I, 



Non-hemolytic 

 (goat cells). 

 Cholera vibrios. 

 Types — original , 

 variant and mid- 

 dle. 



Hemolytic (goat 



cells) . 



El Tor vibrios. 



Types — original 



and variant (?mid- 



dle). 



I 

 O sub-groups II, III, IV, V, VI and indi- 

 vidual races (mostly hemolytic). Para- 

 cholera, cholera-like, and some El Tor 

 vibrios. 



(Types within sub-groups underlined.) 



rides. These are derived from cases of chol- 

 era and have the serological and biochemical 

 characteristics of 0-Group I, Vibrio chol- 

 era. Group I strains are more common than 

 those of Group II, which have, however, 

 been isolated from epidemics with a high 

 mortality. The phospholipid fraction is 

 common to both tj^pes when isolated in the 

 early part of an epidemic but is not found 

 in strains of other groups. The harmless 

 water vibrios, which are so heterogeneous 

 serologically (Taylor and Ahuja, Indian 

 Jour. Med. Res., 26, 1938, 8-32), form a 

 single chemical group with a homogeneous 

 structure. They fall into Group III, which 

 differs in its protein structure from the 

 authentic cholera vibrios and which re- 

 sembles Group II in its polysaccharide. The 

 vibrios of Group IV, which came from El 

 Tor and from chronic vibrio carriers, are 

 believed, on epidemiological grounds, to 

 be harmless, although serological methods 

 have failed to distinguish them from chol- 

 erigenic vibrios. Group V, which, like III 

 and IV, contains protein II, consists, like 

 Group IV, of strains from chronic vibrio 

 carriers. Group VI strains are only rarely 

 isolated in nature, and representatives of 

 this group are generally found among col- 

 lections of old laboratory strains. They 

 appear to be the result of polysaccharide 

 variation from Group I after long-con- 

 tinued growth on artificial media. 



2. Vibrio berolinensis Xeisser, 1893. 

 (Arch. f. Hyg., 19, 1893, 200.) 



be.ro.li.nen'sis. M.L. Berolinum place 

 name, Berlin; M.L. adj. berolinensis of 

 Berlin. 



Curved rods, somewhat smaller than those 

 of Vibrio comma, frequently occurring in 

 pairs. Pleomorphic. Motile by means of a 

 single, polar flagellum. Gram-negative. 



Gelatin colonies: Small, grayish, slightly 

 granular, fragmented; very slow liquefac- 

 tion. 



Gelatin stab: Slow, napiform liquefaction. 



Agar slant: Grayish yellow, moist, glis- 

 tening growth. 



Broth: Turbid, with gray pellicle. 



Litmus milk: No coagulation, no acid. 



Potato: Brownish streak. 



Indole produced. 



Nitrites produced from nitrates. 



Not pathogenic for mice, pigeons or 

 guinea pigs. 



Aerobic, facultative. 



Optimum temperature, 37° C. Minimum, 

 above 10° C. Maximum, less than 60° C. 



Source: Isolated from filtered Spree river 

 water. 



Habitat: Presumably widely distributed 

 in polluted water. 



3. Vibrio metschnikovii GamaMia, 1888. 

 {Vibrio metschnikovi (sic) Gamaleia, Ann. 

 Inst. Past., 2, 1888, 482.) 



metsch.ni.ko'vi.i. Named for Metsch- 

 nikoff, a Russian bacteriologist; M.L. mas. 

 gen.n. metschnikovii of Metschnikoff. 



Curved rods, somewhat shorter and 

 thicker than those of Vibrio comma. Long, 



