BY PROFESSOR CROOKSHANK. . 43 



CONSUMPTION NOT INFECTIOUS, BUT 

 INOCULABLE. 



In conclusion, I would like to draw attention to the 

 theory upon which so much stress has of late been laid, viz., 

 that consumption is infectious. I feel very strongly that this 

 is most misleading, and I think we ought to do all we can to 

 allay the public anxiety which has arisen from the belief that 

 consumption can be caught like scarlet fever. To compare it 

 also to typhoid fever is a great mistake. In typhoid epidemics 

 at home, in India, and recently in South Africa, we know that 

 those in health and out of health fell victims to the disease 

 when they took the poison in food or water. Tuberculosis is 

 not infectious, but it is an inoculable disease. In the Brompton 

 Hospital in London, it has been found that among nurses, 

 porters, physicians, surgeons, in fact among all those who have 

 been in connection with it, the mortality from consumption is 

 within the average of ordinary mortality. If tuberculosis were 

 an infectious disease, and readily conveyed from person to 

 person, the marriage of individuals who become, or are con- 

 sumptive, would be a fruitful source of direct infection. We 

 should hear constantly of instances in which married people 

 had infected each other with tuberculosis. There is a great 

 difference between natural infection and experimental in- 

 oculation, and to this we should attach the greatest importance. 



It cannot be too widely known how virulent is the sputum 

 of consumptive patients when inoculated in susceptible animals, 

 and the habit of spitting in public places and railway carriages, 

 and other conveyances should be prohibited. It is a dis- 

 gusting habit, but there is no need to create a panic or 

 raise an outcry for legislation, making spitting in public places 

 a matter to be dealt with in the Police Court. The sputum 

 of consumptive persons should be disinfected. A good deal of 

 attention has been drawn to the danger of sputum when dried 

 and raised in dust. The virulence is greater when the sputum 

 is moist, and when it has not been exposed to sunlight. That 

 the virus of tubercle is scattered far and wide, and is a dansrer 

 to all is not a theory which is supported by experiment or ex- 

 perience. For example, sputum dried and disinfected by the 

 powerful action of the Australian sun will be rendered inert. 

 Dr. Ransom maintains that in a well ventilated room sputum 

 is harmless. Tubercular sputum kept in the ventilating shaft 

 of a hospital proved virulent to rodents, but similar sputum in 

 a well ventilated and well lighted room became absolutely 



