Alain Vaguet

Du bon usage de l’analyse spatiale et de l’évaluation territoriale dans les politiques sanitaires

Abstract About the good usage of spatial analysis and territorial evaluation in health policies. The first goal of this paper is to introduce the research conducted by PhD fellows in the field of medical geography at the University of Rouen (Upper Normandy). This year, the local authorities declared the Region in a sanitary crisis stage. These researches aim to answer to this social request. The Geomatic and Spatial Analysis methods are highly appreciated; they offer to Geographers and health professionals all together, to produce extremely important documents about distance and accessibility that could help the debate. The second goal of this paper is dealing with theory that leads geographer to go back and forth between the spatial concepts and territorial concepts. This point singles out political interactions such as health district making choices, localisation strategies for sanitary institutions, competition between them and so on. Finally, it conducts to assess the relevance of the territorial policies considering the population uses. How far can we explain the location of a new maternity clinic in city? Can we compare British and French prevalence of pace maker surgery? At the time of mobility, is it necessary to withdraw hospitals of city centres? Is there any link between psychological emergency and precariousness? All these questions are discussed within this paper. The challenge in analysing the present situations would be to assess the part of authorities compared to the role of the population.

Estimating air temperature using MODIS surface temperature images for assessing Aedes aegypti thermal niche in Bangkok, Thailand

Dengue, the most widespread urban vector-borne disease, is transmitted to human by the mosquito Aedes aegypti. Its distribution in urban areas is heterogeneous over time and space. In time, it is linked to seasonal variations such as warm and cold seasons, as well as rainy and dry seasons. In space, it is linked to social and environmental conditions, which alternate between rich and deprived neighborhoods, vegetated and densely built areas. These variations in terms of land cover can affect surface and air temperature. As a result of its influence on the mosquito’s life cycle, temperature plays a crucial part in dengue epidemics potential. Thus, deciphering the thermal variations effects within cities could lead to the identification of precise thermal comfort zones, favorable to the survival of mosquito populations during inter-epidemic periods. The maps that could be produced as a result would enable health authorities to target specific areas. Most cities are equipped with meteorological stations. However, the network is generally not dense enough to precisely identify thermal comfort zones. Remote sensing can be used as a tool to solve this issue. The methodological objective of this paper is to assess the potential of the TVX (Temperature-Vegetation indeX) approach applied to MODIS thermal images for the purpose of estimating daily minimum and maximum air temperatures in the city of Bangkok, Thailand. The TVX approach has been seldom used over urban areas due to the heterogeneous nature of cities in terms of land cover. However, our study shows that in vegetated cities such as Bangkok, the TVX method provides valuable results which can be used to assess thermal niche of A. aegypti.