CHAPTEE X 



TUBERCULOSIS AS A TYPE OF BACTERIAL DISEASE 



Pathology and Bacteriology of Tuberculosis — The Bacillus of Koch — Animal Tuber- 

 culosis, Bovine, Avian, etc. — Bovine and Human Tubercle Bacilli compared 

 — Intercommunicability — Diagnosis of Bovine Tubercle — The Prevention of 

 Tuberculosis — Pseudo-Tuberculosis — Acid-fast Bacteria Allied to the Tubercle 

 Bacillus : in Man, in Animals, in Butter and Mills, in Grass — Differential 

 Diagnosis — Streptothrix Group. 



Tuberculosis is from several points of view the type of bacterial 

 disease which most concerns the public health. Its bacteriology is 

 perhaps more worked out than that of any other disease. Its pre- 

 valence in all parts of the world, and among animals as well as man, 

 makes it a disease of vital importance and interest to man. More- 

 over, the growth of our knowledge respecting it has led to the 

 introduction of methods of prevention, and the world is beginning 

 to understand that a scientific control of this disease is becoming 

 possible. For these reasons it is desirable to treat somewhat fully 

 of the chief facts respecting it. 



Pathology and Bacteriology* 



As far back as 1794, Baillie drew attention to the grey miliary 

 nodules occurring in tuberculous tissue, which gave rise to the term 

 "tubercles." This observation was confirmed by Bayle in 1810. 

 In 1834 Laennec described all caseous deposits as "tubercles," 

 insisting upon four varieties : — 



* A detailed study of tuberculosis from its pathological and bacteriological aspect 

 will be found in La Tubercuhse et son Bacille, part i. , Straus, Professor k la Faculte 

 de M^decine de Paris ; and in Tuberculosis, by Professor Cornet, edited by W. B. 

 James and A. Stengel, 1904. 

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