Résumé
From one field unit trained, equipped, and organized in 1949-later increased to six in 1950, then to eight in the early part of 1951-but which was reduced to seven toward the end of the same year,-we have been able to make extensive fact-finding surveys of 132 towns of 16 provinces in the Philippines continuously for two and one-half years ending on December 31, 1951. The results obtained in these surveys are presented in this paper, with tables and maps showing the incidence and distribution of the diseaseEndemic areas were definitely established in 61 towns of 12 provinces, 123,291 people were examined, and a total of 10,796 cases were found positive on stool examination, giving a general incidence of 12.2%. Of these cases, 5,318 were treated with Fuadin; and 272, with NilodinSnail surveys in all these towns except one (Barugo) revealed many streams and swamps positive for Oncomelania quadrrasi snails. The spotty distribution of the snail population was quite striking-the snail density ranging from a few to several hundreds per square meter. An index of all these spots (816 in all) which were found positive for Oncomelania quadrasi snails was prepared with the corresponding map for each town. These indexes and maps now form the bases of our studies on snail controlOur previous finding in 1950 showing the exceedingly high incidence of intestinal parasitism, reaching 98.79% even in areas where schistosomiasis was not found, was further confirmed in these series of 123,291 stool examinations, with an incidence of 97.82%. We also found an incidence of 85.77% for arcariasis; 52.7% for trichuriasis; and 38.75% for hookworm infectionWith the conclusion of these surveys, it is anticipated that, given more time for the analysis and study of the data obtained, and with the forthcoming technical assistance from the WHO, we may be able to prepare a well-balanced national schistosomiasis control program which we hope will be possible of implementation in the near future. (Summary)