SPECIAL BACTERIOLOGY 



CHAPTER XII 



TYPHOID FEVER 



THE typhoid bacillus was discovered in 1880 by 

 Eberth. It is a motile bacillus about ipoo inch long and 

 4o;ooo inch thick. It decolorizes when stained according 

 to Gram's method, and does not produce spores. Typhoid 

 bacilli grow readily on the ordinary laboratory media, 

 even at room temperature. They do not ferment lac- 

 tose (milk-sugar), so that when* grown in litmus milk 

 or on lactose litmus agar they do not change the color 

 of the medium. 



Typhoid fever is due essentially to the invasion of the 

 body by typhoid bacilli which lodge in certain parts of the 

 wall of the small intestine, causing ulceration of that organ 

 and very severe constitutional symptoms. 



A curious feature of the disease is the development, 

 about the sixth or seventh day of the fever, of small rose- 

 colored spots on the patient's trunk, usually on the abdo- 

 men and on the lower part of the back. 



In typhoid fever the bacilli are found chiefly in certain 

 parts of the wall of the small intestine aftdjn the intestinal 

 contents. In early stages of the disease tfrfcji are also 

 found in the blood, and they are also present in the rose 

 spots already mentioned. In the wall of the intestine 



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