Abstract:Background: The COVID-19 pandemic highlighted the interdependence of human, animal, and environmental health. The recognition of this interdependence has been further reinforced by the growing awareness of climate change as a risk multiplier, exacerbating health threats by accelerating ecological degradation and influencing zoonotic spillover. The Pandemic Agreement, adopted in May 2025, represents the first legally binding instrument to adopt the One Health approach. This study examines the significance and future challenges of the Pandemic Agreement in implementing the One Health approach. Methods: The study combines a literature review on the normative basis and governance challenges of the One Health approach with a survey of relevant soft law instruments and an examination of the text and negotiating history of the Pandemic Agreement. It also considered the impact of general principles and approaches in multilateral environmental agreements (MEAs) as a benchmark for assessing the One Health approach. Results: The Pandemic Agreement builds on the work of the Quadripartite Organizations (FAO, UNEP, WHO, and WOAH) in advancing the One Health approach and introduces legally binding obligations for its implementation, alongside related provisions on prevention and surveillance. However, these obligations are generally assessed as broad and relatively weak, raising questions about their added legal value compared to existing efforts and soft law instruments. Nevertheless, experience from MEAs suggests that even general obligations can shape treaty practice over time. The development of guidelines, recommendations, and decisions by the Conference of the Parties could play a critical role in further operationalizing the One Health approach under the Agreement. Conclusion: The Pandemic Agreement is a legal milestone in promoting the implementation of the One Health approach. However, given the weakness of the related legal obligations, effective implementation of the approach would require continued efforts within the treaty regime after the Agreement enters into force.
Keywords: Climate Change and Planetary Health, One Health, Pandemic Treaty, Global Health Law
