It is rather rare to associate the protection of biodiversity with health. However, the preservation of biodiversity is essential to human life. Any threat to biodiversity — be it the destruction of natural environments, climate change or even air, soil and water pollution — can consist of a direct or indirect threat to human health.
This is a good reason to be interested in the discussions surrounding the COP15 which is taking place in Montreal. This conference focuses more specifically on the creation of a framework aimed at halting the decline of biodiversity in the world. This aligns with the ultimate goal of the Convention on Biological Diversity to live in harmony with nature by 20501 — an objective which is certainly ambitious, but which must succeed in imposing itself in our ways of life and of governance.
More and more researchers and scientists are questioning the links between biodiversity and human health. The findings are rather frightening: the more biodiversity is harmed, the more the risks to human health increase, mainly the risks of the emergence and spread of infectious diseases, some of which are still unknown to science.
Instinctively, wildlife is often perceived as a potential reserve of infections of all kinds, from which it is better to protect oneself by deploying sanitation or eradication measures.
However, field experience shows otherwise. When the balance of an environment is upset, for example, by removing one or more species, the environment weakens.
Researchers have called this the “dilution effect”.2. It can be summed up as follows: a rich biodiversity has a regulatory effect on the prevalence, transmission and virulence of pathogens. To put it another way: the more living species there are, both in number and in variety, the more the probability that a potentially dangerous pathogenic agent will be transmitted to humans or their pets decreases.
The observation is transposed to the side of forests, natural environments and agricultural crops: the more these environments are varied, the better they resist the various disturbances and invasions. The diversity of a given environment is therefore its strength, its solidity, its resilience.
Curiously, this also seems to be the case for humans. Contact with a natural environment, rich and diversified, seems to enrich the human microbiome (all the micro-organisms that inhabit our body), promoting immune balance. This is the biodiversity hypothesis, which has been studied quite convincingly in northern Finland.3
It can be summed up as follows: our health is fundamentally dependent on ecosystems and the different forms of life they harbor. By destroying them and disrupting the functioning of the living, we put ourselves in danger.
It is therefore becoming imperative to ensure the preservation of biodiversity and its prioritization in political orientations.
In the introduction to the final declaration of the COP27 on the climate which has just ended in Egypt, the governments – including that of Canada – recognized the right to health as well as the right to live in a healthy and sustainable.
For the sake of consistency, COP15 must follow suit and offer concrete means to stop the decline of biodiversity and thus honor the right to health. The governmental actors who take part in it must absolutely keep in mind that their decisions will have considerable impacts on the health of the 8 billion humans who live on Earth.
As we struggle to recover from the COVID-19 pandemic and the tsunami effect on our healthcare system, let us offer ourselves the great gift of opening a dialogue on the importance of biodiversity for human health. .