642 



NATURE 



[July 21, 1921 



operation of natural selection is conceivable, but 

 it may be that the differentia between the two 

 classes hes in the acquired immunity due to 

 attacks in early life, or to the vaccinal influence 

 of small repeated doses of the specific contagium. 

 There is little doubt, however, that at the forth- 

 coming conference Prof. Calmette and others will 

 marshal the evidence bearing on this and allied 

 disputed points. 



It is too little known that, even in a country 

 like England, in which tuberculosis has long been 

 endemic, the highest death-rate from this disease 

 occurs during the first five years of life. In the 

 first year after birth one death out of . every 

 twenty-six from all causes is certified to be due 

 to tuberculosis ; the real proportion is much 

 higher, many deaths returned as due to pneu- 

 monia or bronchitis being cases of acute tuber- 

 culosis. Landouzy has stated that 27 per cent, 

 of the deaths in the first two years of life are 

 caused by tuberculosis. The practical lesson from 

 these facts is that in childhood in every race there 

 is but little resistance to the infection of this 

 disease. If, therefore, the total human death- 

 roll at all ages from tuberculosis is to be lowered, 

 it is of supreme importance to prevent children 

 from being exposed to infection during the first 

 five years, and especially during the first two of 

 these years. 



The heavy child mortality from tuberculosis is 

 followed by a lull in the incidence of the disease. 

 Then there occurs a second peak of heavy mor- 

 tality from tuberculosis in its pulmonary form, 

 which in some communities is as high as, or even 

 higher than, that in childhood. Dr. Brownlee 

 has made some ingenious suggestions as to the 

 reasons for the different ages at which this second 

 peak reaches its maximum in various sections of 

 the country, and it is to be hoped that this subject 

 will receive adequate discussion at the forthcom- 

 ing conference. Dr. Brownlee 's suggestion that 

 male adult - tuberculosis has a different origin, 

 according to the shape of the curve, must be 

 tested by the construction of similar curves of 

 female mortality. Moreover, it remains to be 

 shown that the varying age-incidence of maximum 

 mortality from tuberculosis in different areas is not 

 the result of varying exposure to infection and to 

 circumstances calling latent tuberculosis into 

 activity, rather than of a different etiology. 



The double age curve of tuberculosis mortality 



in civilised urban communities throws light on 



the excessive mortality from tuberculosis among 



native races. In this country children who have 



NO, 2699, ^'OL. 107] 



received (and possibly continue to receive) smalB 

 doses of infection not competent to produce active 

 disease acquire a relative immunity, which is over- 

 come only when irritating dust, excessive fatigue, 

 alcoholism, or an acute illness lowers personal 

 resistance to a dangerous point. There was 

 ample experience of these causes of excessive 

 tuberculosis during the Great War. If native 

 races are not thus " salted " in early life, they 

 suffer excessively when exposed to tuberculosis 

 in later life. Hence, as already indicated, the 

 importance of safeguarding young children 

 against protracted exposure to infection, and in 

 later life of the segregation of bedridden cases 

 of tuberculosis and of other patients living in 

 unhygienic circumstances. In addition there are 

 general measures of hygiene and improved nutri- 

 tion the value of which in reducing tuberculosis 

 is beyond question. 



The practical aspect of special tuberculosis work 

 will doubtless be discussed from many points of 

 view at the London conference. It is common 

 ground that the notification of tuberculosis to the 

 Medical Officer of Health is an indispensable link 

 in the chain of preventive measures. Unfor- 

 tunatc*ly, it is well known that notification is 

 imperfectly carried out by a large proportion of 

 medical practitioners, who often do not notify 

 cases for several months after they have come 

 under their care. Thus the possibility of the 

 more active preventive measures necessary is 

 delayed. 



The general relationship of the private prac- 

 titioner to the prevention of disease is of funda- 

 mental importance if rapid progress is to be made. 

 How to harness him to public health work is 

 perhaps the most difficult, as well as the most 

 important, problem of State medicine. At present 

 he is often a hinderer of progress, though in 

 other instances he is the most valuable of State 

 servants. This subject also will doubtless be dis- 

 cussed at the forthcoming conference. 



It cannot be said that the medical machinery of 

 the National Health Insurance Act has helped. 

 When we recall the fact that, even in present cir- 

 cumstances, a panel doctor may sometimes have 

 as many as 3000 insured persons on his list, for 

 whom he receives the annual payment of 1650!!.,. 

 while he is also allowed to take other private 

 patients, it cannot be expected that the adequate 

 examination of all suspected cases of tuberculosis 

 and their early treatment can be satisfactorily 

 undertaken. 



The essential point to be realised in practice — 



