6 
Our total rate of infection with all intestinal worms among the 3,457 persons examined is 
lower than that reported from a similar investigation by any other author. 
The 459 negroes among our cases showed an average of 12.42 infections per 100 persons. 
A group of 746 white persons having similar histories and from the same locality gave an 
average of 4.96 infections per 100 persons. The higher rate of infection among the negroes 
is especially marked in the case of whipworms and dwarf tapeworms. 
The 2,311 males among the 3,457 persons examined gave an average of 10.68 infections per 
100 persons: the 1,146 females gave an average of 12.13 infections per 100 persons. A 
higher rate of infection among females than among males is found in the results of almost all 
other similar investigations, and the total average rates of infection with intestinal worms 
for the two sexes from the combined statistics (except our own) of all authors available to us 
are: Males, 33.47 infections per 100 persons; females, 44.58 infections per 100 persons. The 
higher rate of infections found among males than among females in the 2,324 patients exam- 
ined at the Government Hospital is explained by the presence of over 205 males admitted 
from tropical and subtropical service in the United States Army, who show about 35 infec- 
tions per 100 persons. 
The rates of infection with whipworms, eelworms, and beef tapeworms are higher among 
the females than are the rates for each of these parasites among the males. The greatest dif- 
ference between the sexes appears in the case of the whipworm, the rates being 6.45 and 10.21 
per cent, respectively, for males and females. Pinworms, hookworms, Cochin China worms, 
and dwarf tapeworms each present a higher rate of infection among males. The higher rate 
of infection among males is most marked in the case of the dwarf tapeworm. From the 
combined statistics of all other investigations at our command the greater prevalence among 
females than among males seems to hold for each species of intestinal worm, except dwarf 
tapeworm, so far as reported. For hookworms and Cochin China worms no percentage 
statistics are available regarding the relative prevalence in the two sexes. The one statis- 
tical report we have of the frequency of dwarf tapeworms shows a higher rate of infection 
with this parasite among fnale children than among female childreu. 
The 3,325 persons among the 3,457 persons examined whose ages could be obtained 
were divided into four age groups, namely, those under 15 years of age, those from 15 to 
33 years of age, those from 31 to 50 years of age, and those 51 years of age and older. The 
rate of infection with intestinal worms in each of these groups was as follows: Under 15 
years, 21.14 infections per 100 persons: 15 to 30 years, 15.73 infections per 100 persons; 
31 to 50 years, 11.41 infections per 100 persons; 51 years and older, 7.06 infections per 100 
persons. Whipworms and eelworms are the only parasites which, when taken separately, 
showed a tendency to a gradual decrease in frequency as we pass from theyounger to the 
older groups; pinworms showed little variation at different ages; hookworms showed by 
far their highest rate among persons from 15 to 30 years of age, namely, in the group 
containing most of the soldiers returned from service in the Philippine Islands; with this 
exception the rate of infection with this parasite tended to decrease consistently as the age 
of the patients advanced. Cochin China worms progressively inci eased in frequency as 
we pass from the younger to the older age groups; the dwarf tapeworm showed 4.88 per 
cent of infections among persons under 15 years of age, no infections among those from 15 
to 30 years, and only 0.30 and 0.16 per cent, respectively, in the two succeeding groups; 
the two infections with fat tapeworms occurred one in each of the two older groups. A 
summary of the statistics of other authors regarding the relative frequency of whipwmrms, 
eelworms, and pinworms among persons of different ages indicates a much higher rate of 
infection with each of these parasites among persons under 15 years old than among persons 
above that age; the maximum rates of infection with whipworms and eelworms appear 
among children from 5 to 15 years old, and with pinworms at a still earlier age. 
The 3,334 persons examined at the United States and the Connecticut hospitals were 
divided, according to the length of time they had been in the hospital, into 5 groups, namely, 
patients of less than 1 year’s hospital residence, from 1 to 3 yearn, from 4 to 8 years, from 9 
to 15 years, and those of more than 15 years’ hospital residence. These groups presented, 
