200 APPLIED BACTERIOLOGY 



TETANUS. 



First obtained in pure culture by Kitasato — Morphology — Characters 

 of growth — Method of staining — Method of obtaining pure cultures 

 — Eesistance of spores to heat — Production of artificial immunity in 

 animals — Tetanus antitoxin — Eesearches of Dr. Sidney Martin on 

 the metaboUc products of the tetanus bacillus in the human body. 



Kitasato was the first to obtain pure cultures of the 

 tetanus bacillus, in the year 1889 ; but it had been shown 

 several years previously by Sternberg, and later by Nico- 

 laier, that tetanus could be produced in animals by sub- 

 cutaneous inoculation of garden-earth. 



The bacUlus is a slender rod, and generally shows a 

 spore at one end ; this spore, being larger than the bacillus, 

 gives it the appearance of a drum-stick. The bacillus 

 sometimes grows out into long filaments, in which no 

 spores can be seen. 



Method of Staining. — The tetanus bacillus can be stained 

 by all the usual aniline stains, and by Gram's method. 

 The spores may be demonstrated by the method of double 

 staining given on p. 89 et seq. 



Grovrth. on Media. — The bacillus is a strict anaerobe, and 

 must therefore be grown either in stab culture or in an 

 atmosphere containing no oxygen. In glucose-gelatine or 

 glucose-agar stab culture, a feathery radiated appearance 

 is seen, together with a certain amount of gas-formation, 

 and, in the case of the gelatine, of liquefaction. The 

 organism can only be got to grow with difficulty in gelatine, 

 even when glucose is added, but grows satisfactorily on 

 glucose agar. All cultures possess a peculiar and char- 

 acteristic smell. The organism liquefies solid blood serum, 

 and will not grow on potato. The spores are very resistant 

 to heat and to chemical reagents; in fact, the organism 



