38 The Philippine Journal of Science 1920 
contagious, and usually no definite outbreak of the disease in 
the immediate neighborhood of the affected cases could be 
traced. There was only one instance in 1918 and one in 1919 
of cases occurring in the same household, the persons affected 
being brothers and sisters. 
There is an impression among practicing physicians that 
diphtheria is liable to occur oftener in dqmp, cold weather when 
other catarrhal affections of the respiratory tract are more fre- 
quent; but the statistics of the Health Service for four years 
from 1915 to 1918 and the records of cases treated in San Laz- 
aro Hospital in 1919, presented in Table 2, do not show any 
particular seasonal incidence. 
Table 2 . — Monthly incidence of diphtheria. 
Month. 
Diphtheria in Manila 
(Bureau of Health). 
San Laz- 
aro Hos- 
pital. 
1915 
1916 
1917 
1918 
1919 
January __ _ 
4 
13 
16 
15 
2 
February .._ 
2 
4 
7 
5 
3 
March _ _ __ _____ 
4 
5 
13 
5 
4 
April _____ _ ___ _ _ 
4 
17 
1 
9 
7 
May 
6 
5 
1 
2 
4 
June. _ ___ _ _ 
3 
11 
6 
3 
8 
July _ _ 
6 
7 
4 
2 
6 
August __ _ _ 
3 
16 
9 
0 
3 
September 
4 
13 
8 
1 
7 
October. _ 
7 
7 
6 
1 
2 
November __ 
8 
9 
5 
0 
2 
December _ ... __ __ 
8 
7 
3 
2 
5 
No race is exempt. Among sixty-two cases of diphtheria 
treated in San Lazaro Hospital during the entire year 1919 
and the months of January and February of 1920, there were 
fifty-six Filipinos, three Chinese, two Spaniards, and one 
American mestiza. Among the twenty-seven cases autopsied 
at the College of Medicine and Surgery, University of the Phil- 
ippines from 1908 to 1920, there were twenty-four Filipinos, 
one Russian, one American, and one American mestiza. 
Diphtheria occurs most frequently in children during the 
first five years of life. Among the sixty-two cases admitted to 
San Lazaro Hospital as noted before thirty-four, or 54.8 per 
cent, were children from 2 to 5 years of age; nineteen, or 30.6 
per cent, under 2 years of age; six, or 9.6 per cent, from 6 to 
