Multi-resistant Enterobacteriaceae in yellow-legged gull chicks in their first weeks of life

Wild animal species living in anthropogenic areas are commonly carriers of
antimicrobial resistant bacteria (AMRB), but their role in the
epidemiology of these bacteria is unclear. Several studies on AMRB in
wildlife have been cross-sectional in design and sampled individual
animals at only one point in time. To further understand the role of
wildlife in maintaining and potentially transmitting these bacteria to
humans and livestock, longitudinal studies are needed in which samples are
collected from individual animals over multiple time periods. In Europe,
free-ranging yellow-legged gulls (Larus michahellis) commonly live in
industrialized areas, forage in landfills, and have been found to carry
AMRB in their feces. Using bacterial metagenomics and antimicrobial
resistance characterization, we investigated the spatial and temporal
patterns of AMRB in a nesting colony of yellow-legged gulls from an
industrialized area in southern France. We collected 54 cloacal swabs from
31 yellow-legged gull chicks in 20 nests on three dates in 2016. We found
that AMRB in chicks increased over time and was not spatially structured
within the gull colony. This study highlights the complex occurrence of
AMRB in a free-ranging wildlife species and contributes to our
understanding of the public health risks and implications associated with
ARMB-carrying gulls living in anthropogenic areas.