Abstract
The emergence and rapid spread of zoonotic diseases in Southeast Asia have highlighted the critical necessity of 'One Health' (OH) approaches, which integrate human, animal, and environmental health sectors. This research assesses the extent to which OH principles have been codified and operationalized within the national pandemic response frameworks of ten Southeast Asian nations following the acute phase of the COVID-19 pandemic. Using a mixed-methods approach, we analyzed 42 national policy documents, strategic plans, and legislative frameworks published between 2020 and 2023. Our findings indicate a significant disparity between human health preparedness and environmental health integration. While human and animal health sectors show moderate levels of coordination in 70% of the studied nations, environmental health remains largely siloed, with only 20% of frameworks including specific provisions for ecosystem monitoring or biodiversity management as pandemic prevention strategies. High-income and middle-income nations in the region have made strides in creating inter-ministerial task forces, yet financial allocations for cross-sectoral surveillance systems remain insufficient. The results suggest that while the 'One Health' rhetoric has gained traction in regional discourse, structural barriers—including fragmented legal frameworks and competing budget priorities—hinder full operationalization. The study concludes that regional cooperation, facilitated by bodies such as ASEAN and the WHO Southeast Asia regional flagship programs, is essential to bridge these gaps. Strengthening environmental health surveillance and formalizing inter-sectoral data-sharing protocols are identified as the most urgent priorities for ensuring regional health security in the 2024 post-pandemic era.