Open Defecation, Livestock Ownership, and Child Nutritional Status in India.

South Asian children are among the most severely malnourished worldwide. One prominent hypothesis is that open defecation in the local area exposes children to human fecal pathogens that can cause diarrhea and malnutrition. Much of the existing research uses district-level measures of open defecation, which could mask important local-area variation. A second hypothesis is that animal fecal matter is a major source of exposure. This analysis tested these dual hypotheses using census data collected from 949 villages in Tamil Nadu, India, and a survey conducted in a random sample of 5,000 households in the same area. The final analytic sample consisted of 2,561 children aged 0-10 years. We estimated the association between the measures of village- and household-level open defecation, household livestock ownership, and child height-for-age Z-scores in a regression framework, controlling for potential confounders. Results revealed that village- and household-level open defecations are negatively associated with child height. There was an estimated difference of approximately 0.5 height-for-age Z-score between children living in villages with no open defecation and children in villages where all households practiced open defecation (P = 0.001) and a 0.2 Z-score difference between children living in households that practiced open defecation and those living in households that did not (P = 0.001). Livestock ownership was not associated with child height. Overall, the findings provide evidence on the centrality of open defecation in explaining persistent child malnutrition in India and the higher risk of exposure to human fecal pathogens compared with animal feces in the south Indian context.