17,1 Brillantes: Disease-carrier Problem 113 
ment from the epidemiological standpoint, because there was a 
marked reduction in: 
Percentage of positives out of all cases reported. 
Percentage of mortality of positive cases. 
Percentage of positive carriers. 
Virulence of local strains of diphtheria bacillus (cases and carriers). 
These results are evidently due, if not entirely at least largely, 
to the antidiphtheria campaign undertaken in the previous year. 
During 1917 and 1918 there was a continuous reduction in 
incidence of both cases and carriers, but the mortality rate 
increased. Although this comparatively high mortality is 
puzzling the Health Service, yet, so far, not enough research 
has been done to find an explanation for it. 
CHOLERA CARRIERS 
For quite a long time the frequent reappearance of cholera 
in the Philippines has puzzled the health authorities; so much 
so, that on February 28, 1908, Heiser, then Director of Health, 
announced his hypothesis concerning this frequent reappearance ; 
namely, that the cholera vibrio remains in the sewer system 
(the old Spanish sewers provided for storm water) and by 
contamination of water and food gets into the human intestine. 
He therefore advocated a thorough disinfection of these sewers. 
In view of recently acquired knowledge, this assumption may 
very well be disregarded. It was Marshall who, on the same 
date, first noticed the presence of cholera vibrios in stools of 
convalescents from cholera: in one case for four days and in 
another for ten days, when the patient left the hospital and was 
lost sight of. He emphasized the importance of this occurrence 
in its bearing upon the spread of the disease. 
McLaughlin on October 19, 1908, however, was the first to 
draw attention to the existence of cholera-vibrio carriers. The 
discovery was made in connection with the outbreak in Bilibid 
Prison, when he ordered stool examinations to be made of per- 
sons who had to do with the preparation and handling of food 
and drink. Several healthy persons in this group gave positive 
findings for cholera vibrios ; but upon compliance with his 
orders to wash and disinfect the hands (in a disinfecting so- 
lution), after stool and before eating, no more cases appeared 
in spite of the presence of carriers. Examination of apparently 
healthy persons in Meisic and Tondo shortly after showed 7 
per cent of them to be bacillus carriers. He then stated that 
the existence of carriers, together with bad closet facilities and 
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