Paris | he comes with a bat or it has transited through a pangolin, the coronavirus which has put the world upside down and that the global toll is close to 100 000 dead comes from the animal world, that’s for sure. But it is the human activity that has promoted its passage to the Man, and if nothing changes, many more to come, warn experts.
The “zoonoses”, as we call diseases or infections that are transmitted from animals to humans, are nothing new. Tuberculosis, rabies, toxoplasmosis, malaria… according to the united Nations program for environment (UNEP), 60 % of human infectious diseases have this origin. Figure that rises to 75 % for the disease “emerging”: ebola, HIV, flu, avian, and other SARS or zika…
However, “the emergence of zoonotic diseases is often associated with environmental changes,” which are “usually the result of human activities, the change of land use to climate change,” noted the UNEP in a report of 2016.
“Given the growth of the human population and its use ever more intense of the earth’s resources, destruction of ecosystems, more and more numerous multiplies the contacts” between species, abounds Gwenaël Vourc’h, assistant director of the unit of veterinary epidemiology of the INRAE, a public research institute French.
In cause, deforestation for agriculture, intensive farming, where animals may serve as a “bridge” with the humans (particularly in developing resistance to commonly used antibiotics in industrial agriculture), urbanization and fragmentation of habitats, which alter the balance between species. Not to mention the warming climate that may lead some animals are vectors of disease to thrive where they were not before.
“The process that leads to a microbe such as a virus, of a population of vertebrates -bat-for example – in which there is of course, until the human is complex, but it’s caused by Man (…), the human actions creating the opportunity for microbes to get as close to human populations,” details Anne Larigauderie, executive secretary of IPBES, the panel of experts of the UN on biodiversity.
“The speed of change of the natural areas in the past 50 years is unprecedented in human history. And the direct factor the most important change is the change of use of land,” she continued.
Moreover, beyond the current pandemic, IT is estimated that zoonotic diseases are some 700 000 deaths per year.
A study by american researchers, carried out before the onset of the current epidemic and published on Wednesday, identifies rodents, primates and bats as hosts of the majority of the viruses transmitted to the Human three-quarters (75.8 %). But the pets are also holders of 50 % of zoonoses have been identified.
And if one focuses on the threatened wild species, the study shows that those who share the more viruses with humans are precisely “those whose populations are in decline due to exploitation and habitat loss”.
“We are changing the territories (…), which increases the frequency and intensity of contacts between humans and wild fauna, creating the ideal conditions for transfers viral,” says Christine Johnson, of the veterinary school of the university of California, who led the study, echoing other experts.
The tendency should not be curbed, warns Anne Larigauderie, because the changes of land use, “combined with the increases in trade and travel”, are expected to increase the frequency of pandemics in the future.
The response must be systemic, highlights Gwenaël Vourc’h: “beyond the only response essential for each epidemic, we need to think about our model and, in particular, “to rethink our relationship with the natural ecosystems and the services they provide”.
Anne Larigauderie does not say something else: it calls for a “change transforming to find a solution to this global tragedy”, working towards a “anchor environmental” of the different economic sectors, from finance to fishing, transportation or energy.
“The effective strategies already exist to control most of the neglected zoonoses, the main constraint seemed to lack of investment”, noted the UNEP report in 2016, stressing that “the integrity of the ecosystems underlying the health and human development”.
To 86 years, Jane Goodall has spent most of his life to study and protect the animals, particularly the chimpanzees of Africa, especially from Tanzania. “It was predicted that this was going to happen, and it’s going to reoccur until we learn the lessons,” says the primatologist british. Because for her, the causes of the pandemic are obvious: “our disregard of nature and our lack of respect for the animals with whom we should share the planet.”