The hospital Sink-ome: Pathogen and antimicrobial resistance gene burden in sink-traps across 29 UK hospitals and associations with sink characteristics

Hospital sinks are reservoirs for common healthcare-associated pathogens and antimicrobial resistance (AMR) genes, but there are limited large-scale data on the distribution of this burden across hospitals and associations with sink infrastructure-related features such as design, water chemistry, and usage. Using metagenomics to characterise the microbiome of 287 sink-traps across 29 UK hospitals, we evaluate associations between 49 sink-related features and major clinical pathogen burden, total AMR gene burden, and burden of major extended-spectrum beta-lactamase and carbapenemase genes. We show that higher clinical pathogen burden is associated with higher AMR gene burden and lower sink-trap species diversity and richness. Overgrowth of drug-resistant pathogens in these reservoirs is associated with sink-trap chemistry (including antibiotic residues, iron and alkalinity), moisture, sink location and cleaning frequency. Our study provides novel insights into the ecology of these reservoirs and identifies factors potentially amenable to intervention to reduce the risk hospital sinks pose to patients.