EPIDEMIOLOGY OF TUBERCULOSIS—PARR 483 
changes we may note are a great decrease in the proportion of deaths 
from tuberculosis in infancy, childhood, and adolescence, and even in 
early married life. There has been a relative increase in tuberculosis 
deaths in the middle and later years of life, and there is no longer for 
Whites a peak in the curve representing deaths from tuberculosis. It 
is rather a plateau extending over three or four of the most important 
decades of life. 
Tuberculosis mortality is much higher among males than among 
females. In the States Relations Division of the United States Public 
Health Service there is now a Tuberculosis Control Section headed by 
Dr. H. E. Hilleboe. Tuberculosis mortality in the United States, 1939- 
1941, was reviewed by three Public Health Service workers in Public 
Health Reports for October 1, 1943. They point out that for these 3 
years, 1939-1941, the male death rate (53.6) was 41 percent higher than 
the female rate (38.1). This excess in mortality among males is higher 
for tuberculosis than that from deaths from all causes. For these 
3 years tuberculosis was seventh in numerical importance among the 
leading causes of death. There are very large racial differences in 
tuberculosis mortality, the rate for Negroes in 1940 (123.5) was nearly 
three and one-half times that for Whites (36.6). The rate for Indians, 
Chinese, and other races was about double that for Negroes. Among 
non- Whites tuberculosis was third in numerical importance as a lead- 
ing cause of death. Another point, hotly disputed in the epidemiology 
of tuberculosis, is whether the Negro tuberculosis experience is the re- 
sult of the less favorable socioeconomic conditions under which they 
live or is due to inherent biological racial differences between Whites 
and Negroes. 
Tuberculosis is still among the three leading causes of death for a 
relatively large portion of the life span (15 to 49 years of age). It 
holds first place at ages 15 to 34, second at 35 to 39, and third at 40 to 49. 
For males tuberculosis is among the first three leading causes of death 
at ages 15 to 54, and for females at ages 10 to 44. For Whites only, it is 
among the first three leading causes of deaths at ages 15 to 49 for both 
sexes, ages 20 to 54 for males, and 15 to 44 for females. 
Table 1 reveals the fact that though we have made worth-while prog- 
ress in the fight against tuberculosis this progress compares unfavor- 
ably with advances made in the control of such diseases as typhoid and 
diphtheria, and indeed for the whole group listed together in the table, 
viz, typhoid, malaria, measles, scarlet fever, whooping cough, and diph- 
theria. In 1900 tuberculosis caused only 1.7 times as many deaths as 
this arbitrarily selected group. In 1940 this figure became 7.1 by virtue 
of the more perfect control of the selected group of diseases. Signifi- 
cant, too, is the more marked diminution in the deaths that occur in chil- 
dren under 2 years of age from diarrhea and enteritis. That improve- 
