One Health, One Territory

Urbanisation involves today dramatic anthropogenic modifications of the landscape, causing fragmentation, degradation, replacement or complete loss of natural ecosystems. While rapid urbanisation fragments ecological systems producing smaller and smaller patches within cities, forests or parks are created ex novo –through replantation– to mitigate fragmentation. This double dynamic has produced and is producing a whole new set of socio-ecological interactions between humans, and between humans and other species, from the local to the global levels and scales. Greening and rewilding cities have positive but also negative implications (e.g. introduction of vectors and hosts of infectious diseases) for human and more widely ecosystem health function. This example brings forward the urgent need for systemic and integrated approaches to health looking at the strong interdependence of human health with animal and ecosystem health. The so-called One Health (OH) approach is based on the inexorable links between human, animal, and ecosystem health and on the added value of interdisciplinary and inter-sectoral collaborations in this domain. The OH approach has recently gained a lot of momentum with the impact of human activity on ecosystems and the growing number of emerging infectious diseases and their globalisation (e.g. Ebola, SARS, and Covid-19), however it is still poorly recognised in the context of urban health. Programmes such as “Healthy Cities” from the WHO with more than 20 years and 1000 cities around the world, have neglected this systemic approach to health. On the contrary the OH agenda seems a very promising pathway within the so-called “urban and ecological transition”.