One Health is a concept that emerged in the early 2000s that recognizes the interconnections and health interdependencies among humans, other animals and the shared environments in which we live and interact.
In some cases, these shared environments make it possible for infectious agents — such as viruses — to adapt and move between species. Zoonotic diseases are infectious diseases that are transmitted to humans from animals or vice versa. They include COVID-19, Ebola and HIV, as well as much older diseases like tuberculosis.
Significant changes in our global ecosystem, such as loss of natural habitats, are altering the way humans interact with other animals and the environment, leading to the emergence of new zoonotic diseases. It is currently estimated that approximately three-quarters of emerging infectious diseases in humans have an animal origin.
The COVID-19 pandemic underscores that human health is fundamentally interconnected with the health of other animals (domestic and wild) throughout our shared environment. There is only “one health,” the health of all living organisms in a global ecosystem that, when rapidly altered and imbalanced, puts us all at risk for future pandemics.
There is growing recognition that gaps in local, national and global governance contribute to the emergence and re-emergence of zoonotic diseases. A broad collaboration has been underway to address this for several years.
The tripartite One Health collaboration between the Food and Agriculture Organization of the United Nations (FAO), the World Organisation for Animal Health (OIE) and the World Health Organization (WHO) has, since 2010, been one of the most significant high-level initiatives to strengthen the adoption of the One Health approach to human-animal-environmental health.
The United Nations Environment Programme collaborated with the FAO-OIE-WHO tripartite to establish the One Health High Level Expert Panel (OHHLEP) on Dec. 1. OHHLEP defines the One Health approach as:
“One Health is an integrated, unifying approach that aims to achieve optimal and sustainable health outcomes for people, animals, and ecosystems. It recognizes that the health of humans, domestic and wild animals, plants, and the wider environment (our ecosystems) are closely linked and inter-dependent.
"The approach mobilizes multiple sectors, disciplines and communities at all levels of society to work together to tackle threats to health and ecosystems, while addressing our collective needs for healthy food, water, energy and air, taking action on climate change, and promoting sustainable development.”
An essential part of the pandemic treaty
Under international law, a treaty is a legally binding instrument. An international treaty on pandemics would mandate and support WHO member states to build national, regional and global pandemic capacity and resilience through improved prevention, prediction, preparedness and response.
I am a university professor and the Tier 1 Canada Research Chair in Epidemiology and One Health. As the co-senior author, I am writing on behalf of the authors of a guidance note submitted with the Pandemic Treaty proposal. In it, we explain the central role that an equity-oriented One Health approach could play in pandemic prevention and preparedness.
Addressing risk factors at the human-animal-environment interface — like encroachment of natural habitats by humans — is key to prevention. Enabling better preparedness by, for example, establishing and maintaining highly integrated multi-species surveillance systems, will also require co-ordinating the actions of countries while integrating the medical, public health, veterinary, agronomy, engineering, computer sciences, social sciences and environmental sectors and many more.
There is little integration of One Health principles in existing international treaties and regulations. In our guidance note, we recommend their integration into a future treaty on pandemics. We also explain how this would complement and strengthen the connectivity (the ability to link, communicate and co-ordinate) between existing international agreements.
We propose developing universal metrics for evaluating how the One Health approach is being implemented in different countries.
We recommend fully integrating the One Health approach into all key elements of a pandemic treaty — prevention, surveillance, preparedness and response — and including commitments to financial support. This integration must be done with equity and solidarity in mind to ensure that all will benefit from pandemic prevention. Access to human, animal and ecosystem health diagnostics, treatments and services must be guaranteed and universal.
The inclusion of One Health in a pandemic treaty will help ensure collaboration between and across disciplines and sectors. It will require a strong commitment to increase our One Health knowledge through research and translating its results for a wider audience, with support from the international community.
A pandemic treaty that incorporates One Health would advance pandemic prevention and preparedness, as well as human, animal and environmental health. It would contribute to the protection of biodiversity, reduce activities that increase the risk of pandemics such as illicit wildlife trafficking and harmful land-use changes, and would also avoid catastrophic global financial losses. Such a treaty would also improve the lives of all living beings by reducing the burden on animal and human health care as well as pressure on ecosystems and agricultural lands, and on small producers and communities.
In his closing address to the special assembly, WHO Director-General Tedros Adhanom Ghebreyesus said: “We are one humanity. We have one planet. We have one health.”
What about Canada?
A treaty that integrates the One Health approach to prevention and preparedness for future pandemics at all levels of government, in research, and in the organization of interventions is a major step forward on a global scale.
Canada recently established an interdisciplinary action research network called Global 1HN. It aims to strengthen Canadian leadership in improving the global governance of infectious diseases and antimicrobial resistance. In doing so, it supports the importance of incorporating a One Health approach within a pandemic treaty.
Negotiations underway for such a treaty mark a critical step forward in protecting not only the health of Canadians, but also the interdependent health of all living beings.