Salem G, van de Velden L, Laloé F, Maire B, Ponton A, Traissac P, Prost A.

A survey carried out in Pikine (Senegal) on a sample of 5 groups of children drawn from ecologically representative sections of the town confirms the high prevalence in urban areas of Africa of intestinal infection, especially A. lumbricoides (35.6%), T. trichiura (35.4%), and Giardia (43.7%). The prevalence of A. lumbricoides (35.6%), T. trichiura (35.4%), and Giardia (43.7%). The prevalence of A. lumbricoides and T. trichiura are appreciably higher in the oldest sectors of the town or in those with a better sanitary standard: up to 47.7% for Ascaris and 46% for Trichuris. The use of X2 tests and log-linear analysis demonstrates a significant association between Ascaris and Trichuris. The highest prevalence for Giardia (56.8%) were to be found on the outskirts of the town, where the lowest prevalence of Ascaris (21.7%) and Trichuris (22.9%) were noted; moreover, age-based prevalence for the three parasites vary from one ecological area to another. The relationship between the urbanization process, the variation in environmental factors and intestinal parasitic infection, and the operational implications arising from this geographically-based approach are discussed.