Aerosol-based exposure to opportunistic pathogens originating from hospital sink drains

Hospital room sink drains contain biofilms that harbor opportunistic pathogens. Exposures to these pathogens may occur from aerosolization and droplet dispersion into patient rooms during sink use. This study characterizes aerosolization and droplet generation of sink drain opportunistic pathogens into operational hospital rooms.

Sink drains, sink surfaces, water droplets, aerosols generated during sink use, and settled aerosols were sampled in patient rooms and analyzed via culture-, spectrometry-, and genome-based approaches. Opportunistic pathogens were compared across samples via whole-genome sequencing and single-nucleotide polymorphism analysis. Biofilms and settled aerosols underwent 16S ribosomal deoxyribonucleic acid sequencing to assess the impacts of sink drain biofilms into room bioaerosols.

Analyses suggested sink drain biofilm bacteria dispersed into hospital rooms. Opportunistic pathogens were identified in sink drains, droplets near sinks, and room aerosols. Stenotrophomonas maltophilia isolates from sink drain biofilm and droplets matched at the single-nucleotide level, and microbial community analysis suggested general transmission of bacteria from sink drains into hospital rooms.

Viable opportunistic pathogens from sink drains were present in water droplets and aerosols within patient range, suggesting a potential exposure route.

Hospital sink drain biofilms contributed to the microbiome of hospital room surfaces and air, with microbes generally transmitted from sink drain sources to the room.