Multidrug-resistant bacteria have been found in the wastewater systems of an Irish hospital as part of a study into hospital-acquired infections (HAI).
The study into the wastewater at the University Hospital Limerick was carried out after a ward experienced repeat HAIs, prompting researchers from Queen’s University Belfast and the University of Limerick School of Medicine to examine the water found in sinks, showers, toilets, and plumbing systems across wards.
Published in the Journal of Hospital Infections, the study used a form of analysis called metagenome analysis to profile antibiotic-resistant genes discovered in bacteria present throughout the ward’s wastewater systems.
By cross-referencing these samples with samples found in patients who had been previously admitted to the ward, the researchers were able to determine that the bacteria that infected them was very likely present in the wastewater system.
Senior author of the report and director of research at the University of Limerick School of Medicine, Professor Colum Dunne, detailed how the report could be important in understanding how hospital-acquired infections spread through facilities.
Dunne said: “The risks of antimicrobial or drug resistance in hospitals are recognised widely. However, this is the first study to examine hospital wastewater at this scale and to complete a comprehensive metagenomic profile of the bacteria that exist in the hospital pipework, while also correlating that with infection outbreaks.
“We are hugely appreciative of the openness and cooperation of hospital management and engineering, who are not only open to understanding the microbial communities resident in their water systems but to also putting in place interventions based on this new knowledge.
“This unique study will lead to infection prevention and control improvements that will, ultimately, benefit patients who are admitted to hospital for treatment. The learnings from this are important internationally.”
The study was facilitated when the specific ward in question was undergoing refurbishment, allowing the teams access to pipes and water systems without having to worry about working around patients.
Dr Nuala O’Connell, study co-author and consultant added: “This unique work is pivotal in further understanding the role of the hospital environment, in particular the role of sinks, shower drains and toilets as reservoirs of antimicrobial resistant bacteria.
“Such sites pose a risk for healthcare-associated infections and if we can stop these reservoirs from being established by improved infection control practices, we can hopefully stop patients from acquiring difficult-to-treat infections.
“It is also hoped that this work may inform hospital design teams, particularly around the need for sinks and showers in every clinical area as well as ensuring due consideration is given to their location on patient wards to mitigate against potential risks and infections caused by them.”
