Utilising citizen science data to rapidly assess changing associations between wild birds and avian influenza outbreaks in poultry

High pathogenicity avian influenza virus (HPAIV) is a rapidly evolving virus causing significant economic and environmental harm. Wild birds are a key reservoir of AIVs and an important source of viral incursions into many animal populations, including poultry. However, we lack thorough understanding of which species drive incursions and whether this changes over time. We explored associations between abundances of 152 avian species and cases of HPAI in poultry premises across Great Britain between October-2021 and January-2023. Spatial generalised additive models were used, with species abundance distributions sourced from eBird. Associations were investigated at the species-specific level and across species aggregations. During autumn/winter, associations were generally strongest with waterbirds such as ducks and geese; however, we also found significant associations in groups such as non-native gamebirds, and rapid change in species-specific associations over time. Our results demonstrate the value of citizen science to rapidly explore which wild species could be potential facilitators of disease incursions into well-monitored populations, especially in regions where viral surveillance in wild species is limited. This can be a critical step towards prioritising targeted surveillance that could inform species-specific biosecurity measures; particularly for HPAIV, which has undergone sudden shifts in host-range and continues to rapidly evolve.