Urban waterfowl harbour geographically connected viral communities across Aotearoa New Zealand

Urban waterfowl in Aotearoa New Zealand serve as significant natural reservoirs for viruses that can impact wildlife, livestock, and human health. However, the diversity and spatial distribution of these viral communities have not been extensively studied. Researchers conducted a study to characterise the faecal viromes of urban waterfowl from 13 locations across the country.

The study identified 96 avian viruses, encompassing 50 species, belonging to nine different viral families. Notably, 33 of these viruses were previously unknown. Among these, picornaviruses emerged as the most prevalent viral group. Moreover, several viruses showed close genetic relationships to those previously detected in Australian waterfowl, suggesting a potential distribution of some viral lineages across the Australasian region.

Despite the sampling locations being over 1,500 km apart, the viral composition showed little indication of geographic structuring. There was minimal variation in viral diversity or community composition between the sampling sites. Network analyses further supported this observation, revealing extensive sharing of virus species among the various locations, indicating a lack of geographic structuring in the virome composition among urban waterfowl.

Additionally, the researchers sequenced the complete genome of a low-pathogenic A(H3N8) influenza A virus found in mallards (Anas platyrhynchos) in the southernmost part of Aotearoa. These findings highlight the extensive viral diversity and widespread connectivity among urban waterfowl populations in Aotearoa, offering valuable insights into viral ecology and the potential for widespread virus distribution across the country.