A systematic review of avian influenza virus transmission models: Gaps and opportunities
Highly pathogenic avian influenza virus (HPAIV) increasingly threatens wild birds, poultry, non-human mammals and humans, yet gaps and opportunities in avian influenza virus (AIV) transmission modelling have not been comprehensively synthesized. We reviewed 182 articles published through 2025, categorized dimensions, including modelling approaches, data, host types, biological levels, spatial scales, temporal scales and model objectives, examined associations among these dimensions, and synthesized author-stated limitations and recommendations. Statistical and mechanistic models dominated. Model data centred on population dynamics and demography, disease surveillance, host epidemiology and competence, meteorology and land use and land cover. Most studies focused on poultry or wild birds at regional spatial scales, seasonal/annual and multi-year temporal scales, population or multi-population levels, and were retrospective. Machine learning and decision- making models were less common. Immunity, behaviour and life history, community composition, morphology, viral genetics and viral persistence received less attention. Non-human mammals, individual and community biological levels, local and broader spatial scales, daily temporal scales and prospective modelling were also less frequently modelled. The authors frequently reported limitations related to data availability, surveillance sampling and reporting bias, and model simplification, while commonly recommending improved data quality and greater model complexity and realism.