Early warning systems, mobile technology, and cholera aversion: Evidence from rural Bangladesh.

In Bangladesh, cholera poses a significant environmental health risk. Yet, information about the severity of cholera risk is limited as risk varies over time and changing weather patterns make historical cholera risk predictions less reliable. In this paper, we examine how households use geographically and temporally personalized cholera risk predictions to inform their beliefs and behaviors related to cholera and its aversion. We estimate how access to a smartphone application containing monthly cholera risk predictions unique to a user's home location affects households' beliefs about their cholera risk and their water use and hygiene behaviors. We find that households with access to this application feel more equipped to respond to environmental and health risks and reduce their reliance on surface water for bathing and washing-a common cholera transmission pathway. We do not find that households invest additional resources into drinking water treatment, nor do we find reductions in self-reported cholera incidence. Further, households with a static, non-personalized app containing public health information about cholera exhibit similar patterns of beliefs updating. Taken together, our results suggest that access to dynamic risk information can help households make safer water choices, yet improving design and credibility remain important dimensions for increasing application usability.