Malaria is a disease of great, although not of paramount, importance in the Philippine Islands. It is found chiefly in foothill regions, being transmitted principally by the funestus-minimus sub-group of mosquitoes, which tends to breed in small rivers or streams, or flowing ditches of clear, somewhat shaded, fresh water. There are seasonal variations due either to the drying up of streams or to such an increase in velocity or volume as to make mosquito breeding impossible. Hence, very wet or very dry seasons are not malarious. Flat lands and all areas above 2000 feet in altitude are not malarious. The low coastal plain is not malarious. In general, malaria in the Philippines is a disease of transitional seasons and transitional regions.
As in all tropical regions, malaria control in the Philippines presents a serious economic problem. Probably not more than G$0.05 per capita per annum could be spent in the average small malarious community for control measures. Such measures will have to be continuous for this century and perhaps for the next. The tropics generally are poor in money but rich in time. Malaria control must be planned with this fact in mind and all available, feasible measures utilized. Anti-larval measures can not be omitted from any control program. Such measures, added to bed-nets and anti-malarial drugs should bring about results in time, provided a modest educational campaign and continued research is coincident with them. But in the Tropics no more permanence may be anticipated in malaria control than in road repairs or water-sterilization.