Spatial Overlap of Flood Zones and Cholera Naïve Counties in South Sudan: A Looming Health Crisis

Introduction

South Sudan’s changing climate is reshaping how infectious diseases like cholera spread. Rising temperatures, heavier rains, and worsening floods are placing millions at greater risk. Cholera, a deadly but preventable waterborne disease, increasingly appears in areas with no history of outbreaks. The ongoing outbreak, which started in October 2024, is driven by inadequate water and sanitation infrastructure, widespread displacement caused by conflict and flooding, and an already fragile healthcare system. While the WHO issued a cholera risk map earlier this year, the emergence of cholera in new geographic areas underscores the need to shift from static risk classification to projections of burden during floods, especially in counties previously considered low risk. Studies show that floods nearly double the likelihood of bacterial diarrheal diseases and increase the frequency of cholera outbreaks by a factor of 2.28. These risks are magnified in areas where clean water and sanitation are absent – in a country where 6.4 million people are in need of WASH assistance.