Textbooks on tropical diseases in Africa are well out of date. With the recognition of new and deadly viral infections – Lassa, Marburg, Ebola, Congo–Crimean Hemorrhagic Fever, Rift Valley Fever, and AIDS – the classical descriptions of major diseases such as malaria and yellow fever must be thoroughly revised, and to the roster of more minor ailments can be added dengue, Chikungunya, O’Nyong Nyong, West Nile fever, and others. One must be ready to challenge earlier descriptions of African fevers in general. Malaria in particular has been an “umbrella” diagnosis, which obscured and still obscures the diagnosis of other, sometimes dangerous concomitant illnesses in regions where malaria itself is endemic to hyperendemic. The absolute need for laboratory confirmation to support the clinical impression is slowly being recognized. This must extend beyond the simple demonstration of presence of malaria parasites in the blood. Malaria parasites in the blood certainly prove that the individual in question harbors the parasite. But it is not necessarily proof that the actual immediate infection from which the individual is suffering is related to the existing chronic malarial position. Treatment of the malarial infection is indicated, and is followed almost universally in tropical Africa, with or without confirmation of the presence of malaria parasites. The first diagnosis entertained for all of the viral infections listed above is almost always “malaria.”

It is when the patient does not respond to the antimalarial therapy exhibited that other possible diagnoses are considered. In addition to the viral possibilities, the list should also include influenza, typhoid fever, various rickettsioses, leptospiral infections, bacterial and viral enteropathogenic agents – indeed the range of infections capable of inducing a febrile response.