A large number of bacterial or viral organisms, potentially pathogenic for human populations, exist naturally in oceans, seas, lagoons or estuaries and can even colonise rivers, far upstream from the estuaries.

All of these etiological agents are capable of surviving, either freely or in association with other organisms in the ecosystems, without causing any harm to the neighbouring human populations. In particular, Vibrio cholerae bacteria, responsible for cholera, exist in a number of “stable” non-pathogen forms that can play an important part in keeping trophic chains and the coexistence of species present in the marine environment.

Recent research demonstrates that environmental and/or bioclimatic disturbances can upset these systems and/or modify the conditions enabling their dynamic equilibrium, thereby triggering an outbreak of cholera epidemics in human populations. Cases of cholera have often been identified all along the Mediterranean coastline (Italy, Greece, Turkey, Spain, etc.), and the risk of emergence due to bioclimatic and/or environmental change does exist. This project endeavours to analyse, taking an integrative approach uniting several different scientific partners and disciplines (epidemiological modelling, spatial and geomatic remote detection, physical and biological oceanography, etc.), the risk factors associated with the development of epidemic crises involving Vibrio in the Mediterranean Basin in connection with bioclimatic and/or environmental changes, expected or likely, whether in their average or extreme magnitude.

This project helped create a better understanding of the mechanisms by which infectious agents in the marine domain emerge, re-emerge or are dispersed, with a view toward foresight-based risk management. More specifically, simulations of the future climate expected for the Rhone Delta region and coastal lagoons/ponds will be studied with respect to the related epidemiological risks. This programme facilitated the creation of the theoretical and methodological foundations needed for developing a tool for monitoring and assessing the risks due to this type of etiological agent, highly-pathogenic to human populations. It contributed to and incorporated international research projects on environmental and health issues and was made available to those in charge of monitoring diseases considered a major risk to public health.