“Human-animal interaction has become quite unstable,” warns Dr. Mike Ryan, head of emergencies at the World Health Organization. The factors for the emergence and amplification of the disease have increased. We’ve just seen it with monkeypox, but not only,” he warns.
This monkeypox – ‘monkeypox’ in English – caused by a virus transmitted to humans by infected animals – mostly rodents – is the latest example of the replication of this zoonotic disease. Previously, there was MERS-CoV, Ebola, Zika, covid-19… all infectious diseases that vertebrates could transmit to humans. Some even end up being specifically human, like the coronavirus.
Strong increase for 20 years
According to the World Organization for Animal Health, about 60% of emerging diseases are of zoonotic origin. They appeared thousands of years ago, since humans have intensified their interaction with animals by domesticating them, they have seen their frequency increase dramatically over the past twenty or thirty years.
In the question, “the intensification of travel, which allows them to spread more quickly and in an uncontrolled way,” emphasizes Mark Elwett, head of the Pathogen Detection Laboratory at the Pasteur Institute.
By occupying increasingly large areas of the world, humans also contribute to ecosystem disruption and encourage transmission of viruses.
When we deforest, we lose animals that naturally regulate viruses, allowing them to spread more easily
Thus, the intensification of cultivation in factories increases the risks of the spread of pathogens among animals. Trade in wild animals also increases human exposure to the microbes they may carry.
Deforestation increases the risks of contact between wildlife, domestic animals, and human populations. “When we deforests, we reduce biodiversity, losing animals that naturally regulate viruses, allowing them to spread more easily,” explains Benjamin Roche, a biologist at the Institute of Research for Development (IRD), who specializes in zoonoses.
Better monitoring of ‘urban and terrestrial’ animals
A study published in the journal Nature at the end of April warned that climate change will prompt many animals to flee their ecosystems in search of more livable land. However, by mixing more, the species will transmit more of its viruses, which will promote the emergence of new diseases potentially transmitted to humans. “We need improved monitoring in both urban and wild animals, so we can identify when a pathogen has jumped from one species to another,” says Gregory Albury, an environmental health specialist at Georgetown University in the US and a co-author. the study. “And if the receiving host is urban or close to humans, we should be particularly concerned.”
The study maps out a future “web” of viruses that move from one species to another and grow as the planet warms.
“Today, we have quick and easy investigation methods that allow us to react quickly if new viruses emerge,” reassures Mark Elwett, of the Pasteur Institute. “We are also able to develop vaccines very quickly,” as we have seen with Covid-19.
But it is possible that a whole host of new, potentially dangerous diseases will emerge. We must be prepared,” warns Eric Pfeffer, professor specializing in veterinary infectious diseases at the University of Liverpool (UK) and at the International Livestock Research Institute (Kenya).
This means, he says, “focusing on the general health of the population” in remote environments and “studying the ecology of these natural areas better to understand how different species interact.”
Promote a multidisciplinary approach
Since the beginning of the 2000s, the concept of “One Health” has been put forward: it promotes a multidisciplinary and global approach to health issues with close links between human health, animal health and the environment. The global environmental situation.
In 2021, France also launched the international “Prezode” initiative, which aims to prevent the risks of the emergence of zoonoses and epidemics by strengthening cooperation with the most affected regions of the world.