Human Factors in Parasite Ecology

Abstract

This paper emphasizes particularly group activities that produce conditions favorable for the dissemination of human parasites. War, migrations of populations, and increasing contact between different parts of the world with the development of modern transportation all serve to spread human parasites. Conditions favorable for the transmission of malaria are frequently produced by human projects that increase the breeding? places for the mosquito vectors. The domestication of animals has given man such animal parasitic diseases as trichinosis, and echinococcosis. Specific agric. practices have in a number of cases produced extensive human infection with certain parasites. Thus the methods used in the picking of coffee in Puerto Rico and in the fertilization of mulberry trees by the practice of sericulture in China have produced important endemic centers of hookworm disease. Also, the great prevalence of schisto-somiasis in certain parts of China is associated with the wet cultivation of rice and the extraordinary intensity of the disease in Egypt is produced by the development in modern times of perennial irrigation. When such human relations to parasite dissemination have been adequately studied it is often found that only slight modifications in human habits will serve to bring the parasites under control.