'One Health' Proclaimed in Paris on World Health Day

The World Health Organization (WHO) and France co-hosted a landmark "One Health Summit" on World Health Day (April 7), announcing concrete measures to transform the One Health approach — which recognizes the profound interconnection between human, animal, and environmental health — into real-world action. Heads of state, ministers, scientists, and policymakers gathered in Paris in what is being called a turning point in the history of the One Health movement.

Why 'One Health' — and Why Now

Approximately 60% of known infectious diseases in humans originate in animals, and around 75% of emerging infectious diseases are zoonotic. The COVID-19 pandemic alone resulted in an estimated 15 million deaths and caused trillions of dollars in economic losses globally in 2020–2021.

Climate change, environmental degradation, biodiversity loss, food safety threats, water contamination, and unequal access to health care are all converging to create conditions ripe for future health crises. WHO has warned that without breaking down sectoral silos and responding in an integrated manner, the next crisis cannot be prevented.

"The health of people, animals and the environment we share are inextricably interwoven, and we cannot protect one without protecting all three," said Dr. Tedros Adhanom Ghebreyesus, WHO Director-General.

WHO's Key Actions Announced at the Summit

A Global Network of One Health Institutions. WHO plans to launch a new global network to deliver the objectives of the One Health Joint Plan of Action, inviting Quadripartite partners — WHO, FAO, UNEP, and WOAH — to join. The network will mobilize multidisciplinary expertise and strengthen training and peer learning through the WHO Academy, with a focus on translating international guidance into practical country-level tools.

Stronger Science to Guide Global Action. WHO and Quadripartite partners announced the extension and expansion of the One Health High-Level Expert Panel (OHHLEP), the world's leading scientific advisory body on One Health, reinforcing a science-led approach to policy.

French President Emmanuel Macron stated: "One Health is not just about protecting health — it is about recognizing that we live as one system, where the well-being of humans, animals, and the environment is inseparable. France is determined to move One Health from ambition to implementation. Science must guide our action, and cooperation must be our strength."

A Brief History of the One Health Concept

The One Health concept entered the international policy arena in the early 2000s, driven by the SARS outbreak in 2003 and the H1N1 influenza pandemic in 2009. In 2010, WHO, FAO, and WOAH jointly adopted a shared One Health framework covering chronic diseases, food safety, animal diseases, and environmental health. The COVID-19 pandemic of 2020–2022 dramatically demonstrated the necessity of an integrated response, leading to the 2022 Quadripartite Joint Plan of Action. The Paris Summit marks the transition from planning to implementation.

The outcomes of the Summit will inform ongoing international discussions, including the G7, on preparedness and coordinated responses to health threats at the human, animal, and ecosystem interface.

Looking Ahead [Expert Analysis]

The results of this Summit are likely to be directly incorporated into G7 and broader international governance discussions. As climate change accelerates and biodiversity continues to decline, the One Health approach may be elevated from a health policy framework to a global security priority.

The implications are significant globally. Repeated outbreaks of zoonotic diseases such as avian influenza, combined with climate-driven expansion of vector-borne diseases, make integrated multi-sectoral response frameworks increasingly essential. Nations that actively engage with the emerging global One Health network stand to gain critical early warning capabilities and collaborative research capacity for the threats ahead.

This World Health Day's theme — "Together for health. Stand with science" — reads not merely as a slogan but as a collective declaration by the international community to prevent the next global health crisis before it begins.