Prevalence of Opportunistic Pathogens and Diversity of Microbial Communities in the Water System of a Pulmonary Hospital.

OBJECTIVE

Our objective was to investigate the occurrence of opportunistic pathogens and characterize the bacterial community structures in the water system of a pulmonary hospital.

METHODS

The water samples were collected from automatic and manual faucets in the consulting room, treatment room, dressing room, respiratory ward, and other non-medical rooms in three buildings of the hospital. Quantitative polymerase chain reaction was used to quantify the load of several waterborne opportunistic pathogens and related microorganisms, including spp., spp., and . Illumina sequencing targeting 16S rRNA genes was performed to profile bacterial communities.

RESULTS

The occurrence rates of spp., spp., and were 100%, 100%, and 76%, respectively in all samples. Higher occurrence rates of were observed in the outpatient service building (building 1, 91.7%) and respiration department and wards (building 2, 80%) than in the office building (building 3), where no was found. were more abundant in automatic faucets (average 2.21 × 10 gene copies/L) than in manual faucets (average 1.03 × 10 gene copies/mL) ( < 0.01). , , , , , and were the dominant bacterial phyla. Disinfectant residuals, nitrate, and temperature were found to be the key environmental factors driving microbial community structure shifts in water systems.

CONCLUSION

This study revealed a high level of colonization of water faucets by opportunistic pathogens and provided insight into the characteristics of microbial communities in a hospital water system and approaches to reduce risks of microbial contamination.