Sanitation and health externalities: Resolving the Muslim mortality paradox

In India, Muslims face significantly lower child mortality rates than Hindus, despite Muslim parents being poorer and less educated on average. Because observable characteristics would predict a Muslim disadvantage relative to Hindus, previous studies documenting this robust and persistent pattern have called it a “puzzle” of Muslim mortality. This paper offers a simple solution to the puzzle in the form of an important sanitation externality. Most of India’s population defecates in the open, without the use of toilets or latrines, spreading fecal pathogens that can make children ill. Hindus are 40% more likely than Muslims to do so, and we show that this one difference in sanitation can fully account for the large (18%) child mortality gap between Hindus and Muslims. Building on our finding that religion predicts infant and child mortality only through its association with latrine use, we show that latrine use constitutes an externality rather than a pure private gain: It is the open defecation of one’s neighbors, rather than the household’s own practice, that matters most for child survival. The gradient and mechanism we uncover have important implications for child health and mortality worldwide, since 15% of the world’s population defecates in the open. To put the results in context, we find that moving from a locality where everybody defecates in the open to a locality where nobody defecates in the open is associated with a larger difference in child mortality than moving from the bottom quintile of asset wealth to the top quintile of asset wealth.