Technological advances in serology, immunology, molecular biology, and the emergence of new imaging techniques have profoundly changed the practice of medicine over the past twenty (20) years. These technological developments could have led to the belief that unexplained prolonged fever (IPF) would be a thing of the past, but this is not the case. In Mali, no study has focused on prolonged fevers in adults, hence the purpose of this study, whose objectives were to evaluate the frequency of fevers, and more particularly prolonged fevers, and to determine their etiologies in the Internal Medicine Department of the Point G University Hospital.