Hot and humid days are now associated with higher infant mortality in developing world

Mumbai: The threats of climate change are well-documented and these threats could now extend to infants in the developing world. A recent National Bureau of Economic Research paper by Michael Geruso of University of Texas and development economist Dean Spears of Research Institute for Compassionate Economics (r.i.c.e.) shows that an additional day above 30 degrees Celsius and 55% humidity within the first month of a child’s birth increases neonatal mortality by 0.7 deaths per thousand births. This effect on mortality is an order of magnitude larger than those seen in rich countries.

To calculate this, the paper uses nationally representative data from 53 developing countries across Africa, Asia and Latin America (including India), covering births from the 1980s through 2010 and links this with temperature exposure and child survival. The authors find that the heat and humidity has the strongest effect on infant mortality during the month of birth rather than the period in utero or later in infancy. While some of the hottest places on earth are in Sub-Saharan Africa, the paper shows that the largest incidence of heat-related mortality occurred in Asia where regions are more humid.

According to the authors, this suggests that the impact of high temperature and humidity is biological, rather than an effect through income. High temperatures increase the chance of premature births which in turn increases the risk of neonatal deaths. Another contributing factor is that populations in poor countries are more exposed to outdoor temperatures and have limited access to climate-controlled indoor environments. Finally, pregnant mothers and babies in the developing world are also more likely to be already physically weak due to poor nutrition, infectious disease and poverty.

Policy responses have typically focused on smoothening income in the face of weather uncertainty but these findings suggest that this may insufficient to fully address the infant mortality effects of climate change.

Also read: Heat, Humidity, and Infant Mortality in the Developing World