La borréliose de Lyme : un risque sanitaire émergent dans les forêts franciliennes ?

Lyme borreliosis is the most prevalent and widespread vector-borne disease in temperate zones of the northern hemisphere. It has been considered as an emerging disease, since its recognition as a distinct clinical entity in 1977, and its incidence has increased rapidly during the past decades. In this paper, we briefly examine the emerging character of the disease, first by defining the notion of emergence which is too often ambiguous. From a strict epidemiological standpoint, it is almost impossible to generalize its emergence, especially considering the great variety of situations and contexts (geographical, biological, socio-economic). Presently, Lyme borreliosis seems to pose a new public health problem in heavily urbanized areas due to high population densities and a large number of people that visit urban forests. The hypothesis of an increase in contamination, which is work in progress, is very likely to appear in the Île-de-France region, especially around the forest of Sénart. In order to anticipate potential disease outbreaks in infected areas, it is necessary to consider exposure and risk factors. The analysis of contacts between the itineraries that people adopt in forests and the spaces and environments considered to be “risky” constitutes a privileged avenue of study. Consequently, there is a need to study these spatial dynamics (and to model this kind of contact), as well as to study ways in which it is possible to minimize risk by modifying the landscape