268 CLINICAL BACTERIOLOGY. 



inheritance only the tendency or the predisposition to the 

 disease being transmitted. With indirect inheritance the 

 children of a tuberculous father or mother have inherited 

 a feeble body, a small chest in brief, the tuberculous 

 habitus. They are not tuberculous, but are greatly predis- 

 posed to tuberculosis (sujets tuberculisables, Peter). 



Cases of direct inheritance that is, of congenital tuber- 

 culosis are known both in human pathology and in vet- 

 erinary medicine, but their number is extremely small in 

 comparison with the wide distribution of the disease. The 

 same statement is applicable to tuberculosis in the first few 

 days of life. On the other hand, the mortality from tuber- 

 culosis in early infancy, especially in the first year of life, 

 is quite enormous. Most observers assume that this high 

 mortality is readily explained by the numerous sources of 

 infection to which the child of tuberculous ancestry is ex- 

 posed after birth. The kiss of a tuberculous father, the 

 milk of a tuberculous mother, are equally dangerous, inde- 

 pendently of the fact that with neglect in the treatment of 

 the sputum on the part of the parents there is also afforded 

 frequent opportunity for inhalation of the tubercle-bacilli. 

 That the disease is so prevalent and so fatal in the first 

 year of life is to be explained by the fact that at this period 

 the children are more predisposed, and less resistant, to the 

 tubercle-bacillus than later. The relation in these cases 

 would thus be one of indirect inheritance and not one of 

 true congenital tuberculosis. 



Baumgarten, probably the most earnest advocate of the 

 doctrine of direct inheritance of tuberculosis, takes the 

 ground that the tubercle-bacilli are transmitted to the em- 

 bryo during fetal life. The inherited germ, however, does 

 not proliferate because the tissues of the new-born child, 

 through their vital activity, offer considerable resistance. The 

 bacilli thus to a certain degree remain latent in the lymph- 

 glands, the bone-marrow, etc., later, under the favoring 

 influence of traumatism, intercurrent disease, or diminution 

 in the vital energy of the cells, to unfold their deleterious 

 activity. This view is supported by the observations of 

 Landouzy, Martin, Birch-Hirschfeld, Schmorl, and others, 

 who found tubercle-bacilli in apparently healthy organs 

 from fetuses born of tuberculous mothers. On the other 

 hand, Gartner lays emphasis upon the fact that the infantile 

 cells do not exert an especially injurious influence upon 



