Febrile diseases have contributed to a very large extent to the high mortality and morbidity rate in the tropical regions especially in the low -to-middle-income countries (LMIC). Among other reasons is the confusion arising from the differentiation of the various symptoms that look alike and overlapping. This is in addition to the fact that there is an acute shortage of experienced medical personnel to diagnose cases of febrile diseases. A solution is proffered to this problem in this study by developing a medical decision support system (MDSS) for the diagnosis of febrile diseases. T he system is based on the A gile software life cycle model that allows all the stakeholders to interact in the course of developing the software. Here, the medical doctors, the frontline health workers (FHWs), and the information scientists meet regularly to elicit the requirements, and plan, design , and implement the system. The Analytic Hierarchy Process (AHP) model was used to aggregate the knowledge elicited from the medical doctors which they gathered after interaction with 3253 patients with febrile diseases. The AHP result showed a 90% accuracy with the diagnosis conducted by 60 medical doctors from the collected patients’ data. The developed MDSS is an app deployed for use by the FHWs in an Android -based device with a user -friendly graphical user interface.