SEVERE MALARIA IN SUB-SAHARAN AFRICA - EP IDEMIOLOGIC RISK-FACTORS

Malaria is still a major cause of severe illness among people living i n many tropical countries, particularly in sub-Saharan Africa. This is a well-known evidence but many different and various factors are invo lved which account for an important epidemiological diversity. Factors likely to influence the frequence and severity of the disease are ana lysed : 1- environmental factors : natural biogeography govern the epi demiological patterns of malaria which can be modified by local condit ions such as relief, climate changes, natural disasters and, most impo rtant, human-related activities Like urbanisation, deforestation, migr ation of workers or refugees,... 2- host and parasite factors as famil ial and/or individual susceptibility, strain virulence and level of ch emoresistance of malaria parasites and the size of the inoculum of spo rozoites; 3- socioeconomic factors such as occupation, educational lev el and crowding. Moreover the outcome of an infection depend on the le vel of malaria acquired immunity which is related to the intensity and regularity of transmission.