The Importance of Maintenance : Geospatial Analysis of Cholera Risk and Water and Sanitation Infrastructure in Harare, Zimbabwe

Understanding the specific factors associated with cholera outbreaks is an integral part of designing better approaches to mitigate their impact. This paper uses georeferenced case data from the cholera epidemic that occurred in Harare, Zimbabwe, from September 2018 to January 2019. The paper applies spatio-temporal modeling to understand how the outbreak unfolded and the factors associated with higher risk of being a reported case. The study highlighted a number of findings. First, using call detail records to estimate weekly population movement throughout the city, the results suggest that human movement helps to explain the spatiotemporal patterns of the cases observed. In addition, the results highlight a number of sociodemographic risk factors and suggest that there is a relationship between cholera risk and water infrastructure, with populations living in close proximity to the sewer network with high access to piped water being at higher risk. A possible explanation for this surprising observation is that sewer bursts led to the contamination of the piped water network, turning access to piped water, usually assumed to be protective, into a risk factor. Although further studies are required to test this hypothesis, if it is true, it highlights the importance of maintenance for achieving the Sustainable Development Goals of improved water and sanitation infrastructure