The determination of the presence of intestinal parasites in the study of disorders of the intestine as a routine procedure in the tropics is only natural when one considers that in these countries practically 90 per cent of persons in apparently good health have some kind of parasite in the intestine, and nearly 100 per cent of those who are ill harbor parasites.
Torres in Bahia, Brazil, found infestation in 95.45 per cent of apparently normal persons and in 98, 99 and even 100 per cent of those who entered hospitals. For the sake of brevity, a detailed description of the observations by other investigators in tropical countries will not be given here because it is readily understood that the same percentages apply, more or less, to Central America, Mexico, the West Indies, tropical Africa and other countries with more or less identical climatic conditions. It may be emphasized, however,