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Temperature effects on development of the human filarial parasite #Wuchereria bancrofti$ (Cobbold) (Filaridea : Onchocercidae) in the main Pacific vector #Aedes polynesiensis$ Marks (Diptera : Culicidae) are analysed in relation to ambient climatic conditions. A statistical model of the extrinsic cycle duration as a function of temperature is described and used to distinguish three patterns of #W. bancrofti$ transmission dynamics : continuous, fluctuating and discontinuous, occurring from north to south geographically among French Polynesian archipelagos. In the northerly Marquesas Islands (8-11° S) filariasis transmission is continuous and very active, facilitated by perennially high temperatures combined with constantly high rates of man-vector contact. In the southerly Australes Islands (21-28° S) filariasis transmission is seasonally discontinuous and, during the cooler months (May-September), the model predicts virtually no transmission because the cycle duration exceeds the life expectancy of the vector. In the Society Islands (16-18° S), between the Marquesas and Australes, transmission is predicted to be intermediate as expected from their latitude, with seasonally fluctuating transmission potential. In the Tuamotu Islands (also geographically intermediate : 14-23° S), with theoretically perennial transmission potential, transmission occurs only intermittently, being limited by other human and environmental factors whereby man-vector contact is confined to seasonal agricultural situations. Generally, among French Polynesian archipelagos where #Aedes polynesiensis$ is the vector, the transmission potential for #W. bancrofti$ and resulting disease manifestations of lymphatic filariasis in humans are correlated with ambient temperature due to the degree of southern latitude. (Résumé d'auteur)

La lutte contre la filariose lymphatique fait depuis quelques années l'objet d'une mobilisation internationale importante. Les données concernant la répartition de cette affection en Afrique centrale sont très parcellaires. Nous présentons ici l'état des connaissances au Cameroun. Outre le foyer bien connu de la Province de l'Extrême-Nord, il pourrait exister une zone d'endémie dans la région littorale du pays. Des enquêtes devraient être menées pour dresser une carte fiable des zones d'endémies susceptibles de bénéficier de campagnes de traitement de masse par ivermectine et/ou albendazole. (Résumé d'auteur)