Incidence of diarrhea in children living in urban slums in Salvador, Brazil.

Diarrhea remains a major health issue in developing countries, with high morbidity and mortality rates. Determining the incidence of acute diarrhea in children and its associated factors is crucial to the planning of preventive approaches. The objective of this study was to determine the incidence of diarrhea and to assess some relevant associated factors to it in children younger than 40 months living in two slums of Salvador, Brazil. This is the first prospective cohort, community-based study that was performed in two periurban slums of Salvador, Brazil. Eighty-four children younger than 40 months were randomly selected and visited every other day for one year. The chi-square test was used to evaluate the occurrence of diarrhea and its associated factors. During the surveillance period, 232 diarrhea episodes were identified, resulting in an incidence rate of 2.8 episodes/child/year. In average (mean value of 84 children),each child suffered 11.1 days of diarrhea per year, yielding an average duration of 3.9 days per episode. The highest incidence rates were found among children under one year old. Early weaning, male sex, malnutrition, having a mother younger than 25 years or who considered her child malnourished, missed immunizations and previous pneumonia were associated factors for suffering diarrheal episodes. The rates of incidence and duration of diarrhea that we found are in accordance to those reported by others. Additionally, our results reinforce the importance of environmental and health-related associated factors to the onset of diarrhea.