ANIMAL PARASITES OF MAN. 207 



effects of infections with intestinal worms upon the health of a popula- 

 tion is that carried on by Dr. Shattuck of the Bureau of Health at 

 Bilibid Prison during the time our own investigation was in progress, 

 the results of the same examinations being used as far as practicable in 

 both investigations. 



These results have been placed at our disposal by Dr. Heiser, Director 

 of Health, from the manuscript of his Annual Beport for 1906-7, and 

 are briefly as follows: 



The annual death rate in the prison when it came in charge of the 

 Bureau of Health was 238 per one thousand. The institution of general 

 measures of sanitation reduced this rate to 75 per one thousand where 

 it remained stationary, resisting further reduction. Up to this time 

 little attention had been paid to infection with intestinal worms. In the 

 latter part of 1906, systematic treatment of the prisoners for intestinal 

 worms was begun and vigorously carried out until practically the entire 

 population of the prison had been treated. Following, and, in Dr. 

 Heiser's opinion, largely as the result of this antihelminthic campaign 

 among the prisoners, the death rate dropped to 13 per one thousand 

 per annum. 



Whether or not this apparent relationship between intestinal worms 

 and the death rate at Bilibid will be substantiated by future records 

 at the Prison, or would be confirmed by the institution of a similar 

 campaign throughout the Islands, its significance can scarcely be over- 

 estimated even though ultimately the results should prove to be but a 

 fraction of what was apparently accomplished among the Bilibid prison- 

 ers. It moreover sharply emphasizes the fact that the absence of direct, 

 acute manifestations of intestinal helminthiasis should not blind us 

 to the vital importance of these infections as factors in determining 

 the hygienic condition of a people. 



Applying the rates of infection obtained from the 4,106 prisoners 

 examined at Bilibid to the total population of the Islands (about 

 7,000,000), it would appear that about 5,000,000 persons in the Philip- 

 pines are infected with intestinal worms and that the inhabitants of 

 "the Islands harbor over 9,000,000 infections. The magnitude of these 

 figures indicates in part the tremendous proportions of the problems 

 involved in any radical movement toward improvement of existing 

 conditions, especially when we consider that the situation does not ap- 

 pear to be simplified by any marked confinement of the infections to 

 limited areas. Even a casual knowledge of sanitary conditions prevail- 

 ing throughout the Islands throws additional light upon the difficulties 

 to be encountered and leads to the question whether it_ is practicable 

 at the present time to institute special prophylactic measures directed 

 toward the eradication of intestinal worms, or whether we must content 

 ourselves with the gradual sanitary improvement of the country. 



