[Water resources and health problems in developing countries].

The rapidly increasing use of water for agricultural and hydroelectric development in developing countries is causing serious health problems. These can be divided into two categories; the diseases whose transmission depends on water; and the changes in the life style of the population. We review briefly the principal health problems and analyze the principles to be followed in solving them, and the reasons of the success or failure of health programs.

[The average degree of parasitosis, a criterion for evaluation of the geohelminthic contamination of a population, and for application of santiary measures].

The severity of ascaridiasis in a region depends first of all on the degree of pollution by ascaris ova of the environemtn and consquently on the per diem output of ascaris ova in the stools. Therefore, the importance of ascaridiasis as an endemic disease, depends of course upon the number of positive cases, their prevalence, but still more, it depends upon the intensity of the infection of the diseased population (global parasitic discharge). Practically, this concept of global parasitic discharge is expressed by the number of ascaris ova expelled per gram and per day by a sample of the considered population.