We studied from January to December 1988 the part played by malaria in the etiology of febrile diseases observed in three community clinics of Ouagadougou city (Burkina Faso, West Africa). The diagnosis of malaria attacks was based on the association of a body temperature equal or above 38 degrees C and a parasite density equal or above 10,000 parasitized red blood cells per mm3. We observed that fever attacks were primarily caused by malaria. Among the 5-14 years age group, malaria attacks were responsible for more than 50% of febrile cases and occurred mainly during the rainy season and at the beginning of the dry season (July to October). Ear, nose, throat and lung infections were the other dominant causes of fever attacks and were found during the whole year but especially during the dry season (February, March, September). They were followed by urinary and gastrointestinal infections and other tropical febrile diseases. Clinical diagnosis only of malaria attacks and even more so of fever attacks is poorly reliable.