Mayibout 2 is not a healthy place. The 150 or so people who live in the village, which sits on the south bank of the Ivindo River, deep in the great Minkebe forest in northern Gabon, are used to occasional bouts of diseases such as malaria, dengue, yellow fever and sleeping sickness. Mostly they shrug them off.
But in January 1996, Ebola, a deadly virus then barely known to humans, unexpectedly spilled out of the forest in a wave of small epidemics. The disease killed 21 of 37 villagers who were reported to have been infected, including a number who had carried, skinned, chopped or eaten a chimpanzee from the nearby forest.
Only a decade or two ago it was widely thought that tropical forests and intact natural environments teeming with exotic wildlife threatened humans by harboring the viruses and pathogens that lead to new diseases in humans like Ebola, HIV and dengue.
But a number of researchers today think that it is actually humanity’s destruction of biodiversity that creates the conditions for new viruses and diseases like COVID-19, the viral disease that emerged in China in December 2019, to arisewith profound health and economic impacts in rich and poor countries alike. In fact, a new discipline, planetary health, is emerging that focuses on the increasingly visible connections among the well-being of humans, other living things and entire ecosystems.
Is it possible, then, that it was human activity, such as road building, mining, hunting and logging, that triggered the Ebola epidemics in Mayibout 2 and elsewhere in the 1990s and that is unleashing new terrors today?
We invade tropical forests and other wild landscapes, which harbor so many species of animals and plantsand within those creatures, so many unknown viruses, David Quammen, author of Spillover: Animal Infections and the Next Pandemic, recently wrote in the New York Times. We cut the trees; we kill the animals or cage them and send them to markets. We disrupt ecosystems, and we shake viruses loose from their natural hosts. When that happens, they need a new host. Often, we are it.
Research suggests that outbreaks of animal-borne and other infectious diseases like Ebola, SARS, bird flu and now COVID-19, caused by a novel coronavirus, are on the rise. Pathogens are crossing from animals to humans, and many are now able to spread quickly to new places. The U.S. Centers for Disease Control and Prevention (CDC) estimates that three-quarters of new or emerging diseases that infect humans originate in nonhuman animals.
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