This prospective cohort study has the aim to develop a prognostic tool to predict relapse in patients suffering from visceral leishmaniasis (VL) from VL endemic regions in Ethiopia. Therefore, comprehensive clinical and laboratory characterization of all confirmed VL patients before and during treatment will be performed in order to identify the factors that determine prognosis of the patients. This approach would result in more efficient patient care and would reduce the case fatality and morbidity, and improve follow-up and care for those at risk of VL relapse.