District-level joint risk assessment of highly pathogenic avian influenza H5N1 at the human-animal-environment interface in live bird markets of Bogor, Indonesia

Background and aim: Highly pathogenic avian influenza (HPAI) A(H5N1) continues to be endemic in Indonesia, with live bird markets (LBMs) serving as key points for zoonotic transmission. While national assessments exist, there is a lack of local joint risk assessments (JRAs) specifically focused on LBMs. This study conducted the first district-level, multisectoral JRA of HPAI H5N1 at the human-animal-environment interface in LBMs of Bogor District and Municipality, Indonesia, utilizing the FAO-WHO-WOAH JRA Operational Tool adapted for subnational use.

Materials and methods: A qualitative, participatory JRA was carried out through a structured five-stage process, including governance formation, risk pathway development, stakeholder validation, technical risk analysis, and final consultation. In total, fifty stakeholders from sectors such as human health, animal health, environmental, trade, market, academic, and local government took part. Evidence was triangulated from poultry movement logs, animal and human surveillance data (Integrated Animal Health Information System [iSIKHNAS] and Early Warning and Response System [Sistem Kewaspadaan Dini dan Respons; SKDR), environmental sampling at 15 LBMs, trader interviews, and prior market studies. The risk analysis concentrated on the likelihood, impact, and uncertainty of human H5N1 infection over a 12-month period.

Results: More than 90% of approximately 25 million poultry supplied annually to LBMs originated locally, with marked seasonal surges during religious festivals. Risk pathways highlighted poultry trade networks, market handling practices, slaughtering activities, and inadequate sanitation as key transmission nodes. Two environmental samples tested positive for influenza A, but no H5 subtype or human cases were detected locally since 2017. Consensus-based risk estimation classified the likelihood of at least one human H5N1 infection as low, with minor potential population-level impact. Uncertainty was rated moderate due to limited wild bird surveillance, incomplete environmental sampling, and variable data quality across sectors.

Conclusion: This district-level JRA identified LBMs as persistent but manageable risk nodes for HPAI H5N1 transmission in Bogor. While the current risk to human health was assessed as low, structural and behavioral vulnerabilities justify proactive mitigation. Priority actions include strengthening LBM biosecurity, improving waste management, enhancing environmental surveillance, and reinforcing integrated One Health coordination. The study demonstrates the feasibility and policy relevance of locally implemented JRAs and provides an operational model for decentralized zoonotic risk assessment in endemic settings.