At the time of writing, the world is in the grips of a global pandemic the like of which has never been seen before. The COVID-19 that has swept through countries and continents has caused untold human suffering, social upheaval and economic damage. But while the spread of the current crisis is unprecedented, the new coronavirus follows a number of diseases that have emerged in recent decades, such as Ebola, AIDS, SARS, avian influenza and swine flu. All originated in animals – and there is increasing evidence that humanity’s overexploitation of nature is one of the factors behind the spread of new diseases.
Human activities have significantly altered three-quarters of the land and two-thirds of the ocean, changing the planet to such an extent as to determine the birth of a new era: the “Anthropocene”. Changes in land use that bring wildlife, livestock and humans into closer contact with each other facilitate the spread of diseases, including new strains of bacteria and viruses. Meanwhile, illegal and uncontrolled trade of live wild animals creates dangerous opportunities for contact between humans and the diseases these creatures carry. It is no coincidence that many recent outbreaks have originated in markets that sell a mix of wild and domestic mammals, birds and reptiles, creating the conditions for the development of old and new zoonoses: infectious diseases that can be transmitted from animals to humans.