286 BACTERIA 



Nocard and others have demonstrated the fact that the 

 Bacillus tuberculosis of Koch is the common denominator in 

 all tubercular disease, whatever and wherever its manifest- 

 ations, in all animals. The bacillus, they hold, may, 

 however, experience profound modifications by means of 

 successive passages through the bodies of divers species of 

 animals. But if the modifications which it undergoes as a 

 result of transmissions through birds, for example, are pro- 

 found enough to make the bacillus of avian tubercle a 

 peculiar variety of Koch's bacillus, they are not enough, it is 

 generally believed, to make these bacilli two distinct species. 



We may, therefore, take it for granted that tuberculosis 

 is one and the same disease, with various manifestations, 

 common to man and animals, intercommunicable, and hav- 

 ing but one vera causa : the Bacillus tuberculosis of Koch. 



The Prevention of Tuberculosis. At the present time 

 much attention is being directed to the administrative per- 

 sonal control of tuberculosis. How greatly this is needed 

 in so preventable a disease is evident from a perusal of the 

 following quotation from the Registrar-General's reports. 

 (See opposite page.) 



These figures show a marked decline in the three worst 

 forms of the disease. But this decline is apparently less 

 marked in tabes than in phthisis or tubercular meningitis, 

 i. e., less in the kind of tubercle due to the ingestion of 

 infected milk. Fortunately the State is beginning to realise 

 its duty in regard to preventive measures. The abolition 

 of private slaughter-houses, the protection of meat and milk 

 supplies, the seizure of tuberculous milch cows, and such 

 like measures fall obviously within the jurisdiction of the 

 State rather than the individual, and claim the earnest and 

 urgent attention of the public health departments of states. 1 



1 See the Harben Lectures, November, 1898, by Sir Richard Thome Thorne, 

 Medical Officer to the Local Government Board ; also the Report of the Royal 

 Commission on Tuberculosis, 1896-98. 



