The destruction of ecosystems, the first step towards pandemics

The destruction of ecosystems, the first step towards pandemics

The first reactions to a pandemic like the coronavirus try to find culprits. The pangolin or the bat could be behind the spread of the virus. However, experts point out to humans that, through deforestation, logging and trade in exotic animals, they are exposed to these diseases.

Confinement makes us look guilty. Some, loaded with racism, point to "the damn Chinese viruses." Others put the index on the pangolin, while searching the networks for an image that gives them the opportunity, at least, to know what this exotic animal is like. There are also those who, far from closing ranks in moments of unity, charge against the Government, which seems to have failed to manage the coronavirus health crisis. You can even find people who strongly defend that this viral crisis responds to hidden interests, which has been denied by science in a recent study that denies that COVID-19 could have been born in a laboratory.

Beyond conjecture, this global pandemic brings to the table evidence regarding the sudden appearance of unknown viruses in societies: human beings and their actions on the environment favor that these types of organisms, hidden in nature, enter into contact with companies. “We simplify ecosystems, we reduce the number of species and we lose biodiversity. This makes intermediate species disappear that act as a barrier, favoring that we are in contact with other species with which we never had contact and, therefore, more exposed ”, he explains toPublicFernando Valladares, doctor in Biological Sciences and researcher at the Higher Center for Scientific Research (CSIC).

The reduction of the Earth to a product is, without a doubt, a condition to take into account when understanding the reason why this type of disease - some more virulent than others - is spreading throughout the world with increasing numbers. periodicity. "There is a scientifically proven link between the destruction of natural environments and the appearance of new diseases", explains Juantxo López de Uralde, environmental deputy and president of the Congressional Ecological Transition Commission. “With the destruction of tropical forests for, for example, monoculture plantations, species disappear and others seek refuge in areas closer to humans, who interact with the animal through trade in species, or directly eat it, and it ends up getting infected ”, sums up the expert.

The problem of clearing forests to fill pockets goes beyond environmental morality and opens the door to increasing the risks of spreading disease. As explained this week in the BBCPeter Daszak, ecologist and key researcher in the discovery of bats as the origin of SARS, it is estimated that around 1.7 million undiscovered viruses hide in the most remote areas of the planet, which reveals the extent to which spaces can be reversed. natural at the whim of the economy - be it deforestation or trafficking in exotic species - can increase the risks of a pandemic like the current one.

“One of the most important messages during this crisis is that biodiversity protects us. It is something that should be clear. We are spending a huge amount of money to contain a failure, which is what the coronavirus is, because success is not overcoming the pandemic, but rather that it does not occur and for this it is necessary to recover ecosystems and keep them intact, ”Valladares warns, that focuses on the value of nature as a "barrier" to this type of phenomenon.

In the case of the coronavirus, the main theses speak of the bat as one of the animals that could have spread the virus. What is not clear is how and if there were intermediate animals - here the pangolin could come into play - that had been infected by the flying mammal and could have spread the virus. In any case, the similarities with the spread of other pandemics such as Sars or Ebola are evident: human beings who come into contact with animals with which in the past they had no relationship.

This irruption of the human being in nature becomes, according to a recent report by the World Wide Fund for Nature (WWF), in a “boomerang” that turns against global health. Thus, the expansion of COVI-19 is due, according to the first publications, to a zoonosis process that, far from having its origin in the markets of exotic species, begins in the activities of deforestation and construction of infrastructures in forested territories. This is the first step for practically unknown animals to get closer to humans.

The bats were behind SARS, the monkey could be the zero patient of HIV, the chickens, in turn, spread the bird flu and, now, the pangolin and the bat are singled out as possible transmitters of COVID-19. "We tend to look for an origin and we always turn to the animal, when the real culprit is the human being, who has directly or indirectly removed the species from their ecosystems", argues López de Uralde.

"Until now we have conserved ecosystems out of pure ethics, without knowing that these ecosystems protect us," adds Valladares, emphasizing that this crisis can serve to understand the protection value that nature has. Thus, the expert emphasizes that the "victory" over the coronavirus passes through the "complexification" of ecosystems and for this, as he explains, it is necessary to "change the social and economic structures" that favor the depravity of nature. "It is the only way to ensure that within a while another unknown virus does not reach civilizations," he says.

Video: How Deforestation Helps Viruses Spread (October 2020).