[Historical epidemiology of malaria in the archipelago of the Mascarenes (Indian Ocean)].

The Mascarenes Islands (Mauritius, Rodrigues and Reunion) have been for the last few centuries a place of rest and convalescence for sailors, soldiers and inhabitants of the other regions of the Indian Ocean affected by "intermittent fevers". In the middle of the nineteenth century a severe and deadly malaria epidemic occurred first in Mauritius and then in Reunion Island. It took a century to bring the disease under control, but this has in no way diminished the risk of its re-introduction. Comparative study of the way the disease appeared and got established in these two islands and not in the adjoining ones (Rodrigues, Chagos, Seychelles) leads us to formulate the hypothesis that massive deforestation for sugar cane cultivation created a favourable environment for the implantation of the malaria vector, the african origin of which is beyond doubt. The evolution of the environment, subjected to natural catastrophe (cyclones) and to human activities (often as a consequence of economic development) has exerted pressure on the vector which in a way gives an answer of the development of the disease over time. This study highlights the importance of epidemiological analysis of the history of major communicable diseases not only in the cognitive context but also in predicting probable public health problem arising from environmental modifications.