In our Cholera Update Series, produced in collaboration with the World Health Organization (WHO), we highlight the role of disease surveillance in detecting and responding to South Sudan’s ongoing cholera outbreak. Speaking on the Miraya Breakfast Show, WHO's Public Health Officer Sheila Baya explains that the outbreak was initially identified through surveillance systems, triggered by the arrival of refugees from Sudan where cholera was already spreading. She notes that case numbers have declined in areas where vaccination campaigns have been carried out. However, she also expresses concern over rising cases in other locations still experiencing an upsurge.