D IARRHEA WAS one of the leading causes of disease and death among children throughout the world until the first decade of the 20th century (Kain, 1991). Presently, diarrhea is no longer regarded as a public health problem in developed countries (World Health Organization, 1984). Advancement is mostly attributable to improved sanitary environments, availability of pure water, sanitary control of food and beverages, and increased public and individual concern for hygiene (Mahmud, Jalil, Karlberg, & Lindblad, 1993). Now, at the end of the 20th century, diarrhea and malnutrition continue to constitute a major threat to children in impoverished vicinities in developing countries worldwide. (See Table 1 for definition of terms.) A review of the literature indicates that studies can be difficult to compare because some report episodes per year (Baqui et al., 1992; Bhan et al., 1986; Government of Pakistan, 1984; Huttly et al., 1989; Kumar, Datta, Wadhwa, & Singhi, 1985; Motarjemi, Kaferstein, Moy, & Quevedo, 1993; Sircar et al., 1984), whereas others report in days per year (Cruz et al., in press b, cited in Torun & Chew, 1991; Dialogue on Diarrhea, 1989: Torun & Chew, 1991), and yet others report both (Black, Brown, Becker, & Yunus, 1982). It should be noted that children under 5 years of age are vulnerable to morbidity and mortality from diarrhea (Feachem, 1986; Motarjemi et al., 1993; Tomkins & Watson, 1989). In Pakistan, infants under 1 year old are extremely vulnerable to morbidity and mortality from diarrhea; the reported death rate is 200,000 annually (Dialogue on Diarrhea, 1989). Evidence of the pandemic nature of diarrhea and malnutrition in children can be found in research from the Indian subcontinent, Asia, Africa, and Central and South America. For example, in rural Bangladesh, the prevalence of diarrheal illness under the age of 5 years has been approximated to be 12.8 days per 100 child-days, which indicates that each child spent 46 days per year with diarrhea (Black et al., 1982). Other studies from Indian villages in children under 5 years of age showed varied incidences of 0.7 episodes per child per year (Bhan et al., 1986) to 2.2 episodes per child per year (Oyejide & Fagbami, 1988). The incidence in urban Nigerian children is 3.2 episodes per child per year (Oyejide & Fagbami, 1988), and in poor Peruvian children of Lima, 9.8 episodes per child per year (Lopez, Romana, Brown, Black, & Kanashiro, 1989). Findings from the Pan American study indicate diarrheal diseases as the major cause of death in children under 5 years of age, accounting for 29% of the total (Sanders & Carver, 1985, p. 17). Although mortality is not as great a problem in developed countries, in the United States children 5 years of age and younger experience 20 million episodes of diarrhea each year, leading to several million doctor visits, 200,000 hospitalizations, and approximately 400 deaths (Duggan, Santosham, & Glass, 1992). It has been reported that much of this morbidity is the result of dehydration associated with acute watery diarrhea (Diarrhea Treatment, 1993; Duggan, Santosham, & Glass, 1992). Malnutrition is also a leading cause of morbidity and mortality in developing countries (Badruddin, 1986; Jalil, 1991; Mull, 1991; Torun & Chew, 1991). According to The Progress of Nations (1993) report, 17% of the children younger than 5 years of age in Ecuador are malnourished compared with the South