This lesser-known subject is becoming increasingly important. Since 2007, most people have been living in cities. Let's stop imagining the city as a "strictly unnatural space", removed from "wild" ecosystems and isolated from everything else. It's true that, at first, humans destroy and settle in, but biodiversity quickly returns and takes advantage of new, highly specific environments, like the new species of mosquito that recently appeared on the London Underground! Living things benefit from the verticality, the often milder temperatures in winter, the less extensive use of plant protection products, the absence of predators and the presence of... lots of humans! This will not be without consequences for the spread of infectious diseases. Let's advocate the return of biodiversity to the city and the "greening" of cities, the maintenance of green and blue grids, the development of participatory science, bio-inspiration and so on. A genuine urban ecology, with all its underlying energy aspects, needs to be developed, enabling the development of new practices and technologies vital to human well-being.
In terms of public health, there has recently been a proliferation of examples demonstrating the impact of climate disruption and biodiversity loss, such as the sometimes spectacular development of infectious, autoimmune and allergic diseases. Biodiversity depletion leads to disharmony of systems and much greater conditions for the dissemination and virulence of pathogens. Metapopulations of microbial eukaryotes appear to be ubiquitous. Biodiversity losses favour parasite dissemination. Recent interest in the evolution of the intestinal microbiota in humans has led to some astonishing and major discoveries: 300 diseases (some of them lifespan-related) have appeared in humans since 1940. Yellow fever, Ebola fever, dengue fever, chikungunya, malaria, SARS, leishmaniasis, tripanosomiasis, Lyme borreliosis, hantavirus, leptospirosis, etc., are pathologies that are highly dependent on fluctuations in biodiversity: host changes are crucial to monitor and study. Autoimmune and allergic diseases are also on the rise, and are a major cause for concern.
