CHAPTER XXVII. 

 TUBERCULOSIS. 



BACILLUS TUBERCULOSIS (KOCH).* 



General Characteristics. A non-motile, non-flagellate, non-spor- 

 ogenous, non-liquefying, non-chromogenic, non-aerogenic, distinctly 

 aerobic, acid-resisting, purely parasitic, highly pathogenic organism, 

 staining by special methods and by Gram's method. Commonly oc- 

 curring in the form of slender, slightly curved rods with rounded ends, 

 not infrequently showing branches, hence probably not a bacillus, but 

 an organism belonging to the higher bacteria. It does not produce 

 indol or acidulate or coagulate milk. 



Tuberculosis is one of the most dreadful and, unfor- 

 tunately, one of the most common diseases. It is no re- 

 specter of persons, but affects alike the young and old, the 

 rich and poor, the male and female, the enlightened and 

 savage, the human being and the lower animals. It is the 

 most common cause of death among human beings, and is 

 common among animals, occurring with great frequency 

 among cattle, less frequently among goats and hogs, and 

 sometimes, though rarely, among sheep, horses, dogs, and 

 cats. 



Wild animals under natural conditions seem to escape 

 the disease, but when caged and kept in zoologic gardens, 

 even the most resistant of them lions, tigers, etc. are 

 said at times to succumb to it, while it is the most common 

 cause of death among captive monkeys. 



The disease is not limited to mammals, but occurs in a 

 somewhat modified form in birds, and it is said even at 

 times to affect reptiles, batrachians, and fishes. 



The disease has been recognized for centuries ; and though, 

 before the advent of the microscope, it was not always clearly 

 differentiated from cancer, it has not only left unmistakable 

 signs of its existence in the early literature of medicine, but 

 has also imprinted itself upon the statute-books of some 

 countries, as the kingdom of Naples, where its ravages were 

 great and the means taken for its prevention radical. 



* "Berliner klin. Wochenschrift," 1882, 15. 

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