PATHOGENIC BACTERIA. 309 



Ordinary suppuration may be produced by the typhoid 

 bacillus, but most suppurative affections during or following 

 typhoid fever are mixed infections, or are due to the ordi- 

 nary pyogenic bacteria. 



Typhoid fever is transmitted chiefly through the medium 

 of water. It is sometimes conveyed by milk, green vege- 

 tables and oysters. Infection through the medium of dust, 

 and by the hands and clothing probably occurs, but not com- 

 monly. Under certain circumstances the bacilli may be 

 carried by flies. 1 In caring for cases of typhoid fever the 

 stools, urine, sputum and linen should be disinfected. Per- 

 sons handling the patient should wash and disinfect their 

 hands. 



The injection of typhoid bacilli which have been killed by heat has 

 been advised (by Wright) as a preventive measure. The results appear 

 to have been partially successful, but the method is still being actively 

 studied. 



Bacillus coli communis (Bacterium coli commune of 

 Escherich, probably the same as Bacillus Neapolitanus of 

 Emmerich, often called simply the colon bacillus. Passet 

 described an organism under the name of Bacillus pyo- 

 genes fcetidus, from .foul pus and mixed infections, which 

 is probably the same as B. coli communis). A bacillus with 

 rounded ends, frequently of a short, oval form, when it 

 may be difficult to distinguish from micrococci ; often 

 longer; often forming threads. It is slightly motile, hav- 

 ing several flagella. It does not form spores. It stains 

 with the ordinary aniline dyes and is decolorized by Gram's 

 method. It is facultative anaerobic. It grows well at the 

 room temperature, but more rapidly in the incubator. It 

 does not liquefy gelatin. In gelatin plates the surface 

 colonies are of a bluish-white color; the centers are denser 



1 Vaughan, Philadelphia Medical Journal, June 9, 1900. 



