1908] The Present Phase of the Tuberculosis ProUem. 277 



WEEKLY EVENING MEETING, 



Friday, May 15, 1908. 



His Grace The Duke of Northumberland, K.G. P.C. D.C.L. 

 Sc.D. F.R.S., President, in the Chair. 



Herbert Timbrell Bulstrode, M.A. M.D. D.P.H. 



The Present Phase of the Tuberculosis Problem. 



This lecture will deal with certain aspects of the tuberculosis 

 question. 



The Nature of Tuberculosis. 



It is desirable, in the first instance, to indicate the sense in which 

 the term tuberculosis is here employed. 



Tuberculosis is a diseased condition which is brought about by 

 the inter-reaction of a vegetable parasite — the tubercle bacillus — 

 and a susceptible animal host. When the micro-organism succeeds in 

 obtaining a foothold in the lungs, the disease produced is known as 

 Pulmonary Tuberculosis, or, in popular terminology. Phthisis or 

 Consumption. This pulmonary tulierculosis is divided into " open " 

 and " closed " ; " open " when the lung tissue is l)reaking down and 

 bacilli are expectorated, " closed " when no tuljercle l)acilli are thus 

 set free. This distinction between " open " and " closed " is of con- 

 siderable importance, both from an epidemiological and administrative 

 standpoint. 



When there is what may be termed an infective reaction between 

 the parasite and the host in the intestines, glands, bones, joints, or 

 other localities, tuberculosis of these parts ensues. 



Almost every organ of the body is liable to the disease, and it has 

 to be borne in mind that tul)erculosis is in no sense limited to the 

 human species ; practically all domesticated animals, the ox, the pig, 

 the horse, the sheep, the cat, the dog, and the fowl, in some degree 

 are liable to develop the malady. 



Prolonged residence in the tissues of one or other of these animals 

 has, it may be believed, induced certain changes in the tubercle 

 bacilli. It is probable that they are all allied, and sometimes indeed 

 they are more or less interchangeable either at once or after " passage " 

 through other animals. 



There is advantage in laying stress on the circumstance that twc 

 factors are necessary to induce tuberculosis, the bacillus and a certain 

 condition of the " soil " or tissues of the host. Since the discovery of 



