The world is a vast and complex ecosystem. Like everything ecosystem, is essentially made up of living elements (plants and animals, including humans) and inorganic elements (geological substrate, water, air), and the interactions that are established between all of its components. Any alteration of any one of the multiple elements of this immense ecosystem involves more or less serious and more or less extensive consequences on the ecological scale.
Certainly, there have always been various alterations on the planet that have had notable consequences. The extinction of dinosaursglaciations and deglaciations, volcanoes…, but the altering factor has always been linked to nature itself.
However, there is a key and disturbing element among the living beings that make up this ecosystem: human being. American sociologist AH Hawley said, “Man is the most powerful species to alter ecosystems and ecological processes…instead of adapting his activities to the relationships of natural life, controls and regulates the biotic community to meet its needs“. The human being is, if not the only one, one of the rare species which, in order to survive, does not adapt to the environment, but rather modifies it and makes it adapt to its needs. And that is why it uses resources and tools capable of altering the fragile balance to unsuspected limits.We speak of the Anthropocene to define a stage which for some begins at the end of the 18th century with the use of steam engine and the beginning of the industrial revolution and which has made its qualitative leap since the 50s of the last century, with the excessive use of fossil fuels and the irresistible generation of greenhouse gases and other pollutants, which alter the vital conditions of the Earth. The biotope, the environmental environment, is sick.
Yes to global warmingwith sea level rise, extreme weather events, floods and droughts and the like, we add the chemical contamination by pesticides and other productsdeforestation or changes in land use, intensive animal husbandry or the trade and consumption of exotic species caused by our way of life and which lead to greater and more intimate movements and contact with animal species, previously isolated from humans and, in many cases, carriers of pathogenic microorganisms and diseases, can jump species and affect humans.
One more element, little valued until now: the environment is not only populated by animals and plants. There is also, and with great importance, microorganisms: the microbiome, many of which reside in the human body and are essential (the microbiota). If this microscopic world is not “healthy”, it also affects human beings and their health.
Add to cocktail globalization and the ease and speed of travel around the world and we will see how easily and efficiently these infectious diseases of animal origin, favored by environmental changes, spread and become pandemics. Covid-19 has reminded us, if we didn’t already know it, of the importance and close interdependence between environmental health, animal health and human health. Human beings cannot be healthy if everything around them is not healthy: the environment and animals, domestic and wild.
This fact, of extreme importance, has led the WHO, on its World Health Day, celebrated every April 7, to have as its motto this year “Our planet, our health”.
Medicine in isolation cannot guarantee that we will not get sick. Close collaboration with the world of veterinary and environmental sciences is necessary. A single strategy aimed at a single objective is necessary: the health of the Earth and everything on it. This is the “One Health” strategy promoted by the WHO, the OIE (organization for animal health) and the FAO (Food and Agriculture Organization), and which can only be summed up as If we change the current lifestyles of human society, we can make the environment and the animal world healthier and, in turn, improve the health of humans. It depends on us.