FAMILY PARVOBACTERIACEAE 



585 



Where the relationship to growth accessory factors is known, the following table 

 may serve as a key : 



1. Hemophilus influenzae (Lehmann 

 and Neumann) Winslow et al. (Koch, 

 Wiener med. Wchnschr., 33, 1883, 1550, 

 Weeks, New York Med. Record, 31, 

 1887, 571; Influenzabacillus, Pfeiffer, 

 Deutsche med. Wchnschr., 1892, 28; 

 Ztschr. f. Hyg., 13, 1893, 357; Bacterium 

 influenzae Lehmann and Neumann, Bnkt. 

 Diag., 1 Aufl., 2, 1896, 187; Bacillus in- 

 fluenzae Kruse, in Flligge, Die Mikro- 

 organismen, 3 Aufl., 2, 1896, 434; Bac- 

 terium aegyptiacum Lehmann and 

 Neumann, Bakt. Diag., 2 Aufl., 2, 1899, 

 191 ; Hemophilus meningitidis cerebro- 

 spinalis septicemiae Cohen, Ann. Inst. 

 Past., 23, 1909, 273; Winslow et al., 

 Jour. Bact., 2, 1917, 561; Coccobacillus 

 pfeifferi Neveu-Lemaire, Precis Parasi- 

 tol. Hum., 5th ed., 1921, 20; Hemophilus 

 conjunctivitidis Bergey et al.. Manual, 

 1st ed., 1923, 270.) From influenza, a 

 disease of the respiratory tract. 



Common name : The Koch-Weeks 

 Bacillus. 



Very small rods: 0.2 to 0.3 by 0.5 to 

 2.0 microns, occurring singly and in pairs, 

 occasionally in short chains, and at times 

 long thread forms are seen. Frequently 

 show a marked tendency to bipolar stain- 

 ing. Some strains are encapsulated. 

 Non-motile. Gram-negative. 



Requires both the factors X and V for 

 its growth. 



Gelatin colonies: No growth. 



Gelatin stab : No growth . 



Blood agar colonies: Small, circular, 

 transi)arent, homogeneous, entire. 

 Satellitism with Staphylococcus. 



Blood agar slant : Thin, filiform, trans- 

 parent growth. 



Chocolate agar slant : Luxuriant 

 growth. 



Blood broth: Slightly turbid. No 

 hemolysis. 



litmus milk, with blood : Some strains 

 render it very slightly alkaline. 



Sterilized potato slant : No growth. 



Fresh unheated sterile potato added 

 to broth favors development. 



Indole is formed by some strains. 



Nitrites are produced from nitrates. 



Some strains attack none of the carbo- 

 hydrates, while other strains attack 

 various carbohydrates, provided a suit- 

 able medium is used. IVIannitol and 

 lactose never fermented. 



Pathogenic. 



Aerobic, facultative. 



Optimum temperature 37°C. Maxi- 

 mum 43°C. Minimum 26° to 27°C. 

 Killed at 55°C for thirty minutes. 



Source : Isolated by Pfeiffer in cases of 

 influenza. Found in conjunctiva, naso- 

 pharynx, sputum, sinuses, cerebrospinal 

 fluid, blood, and pus from joints. 



Habitat: Respiratory tract. A cause 

 of acute respiratory infections, of acute 

 conjunctivitis, and of purulent meningi- 

 tis of children, rarely of adults. Re- 



