A study on detection of waterborne pathogens in hospital water systems for prevention of healthcare-associated infections: A prospective cross-sectional observational study.
DOI:
https://doi.org/10.51168/xgm0fh58Keywords:
Healthcare-associated infections, Hospital water systems, Pseudomonas aeruginosa, Biofilm, Waterborne pathogens, Microbiological surveillanceAbstract
Background
Hospital water systems can act as reservoirs of opportunistic waterborne pathogens. Biofilm formation within pipelines, taps and distal outlets promotes microbial persistence and increases healthcare-associated infection risk.
Objectives
To detect waterborne pathogens in hospital water systems and assess their relevance to healthcare-associated infection prevention.
Methods
This prospective cross-sectional observational study was conducted over 12 months in a tertiary care teaching hospital. Ninety environmental samples were examined: 35 tap water samples, 35 tap swabs, 5 reverse osmosis water samples, 10 air-conditioning water samples and 5 drinking water samples from intensive care units, wards, operation theatres, laboratories, dialysis areas and water outlets. Samples were processed using standard microbiological methods with Blood agar, MacConkey agar and Buffered Charcoal Yeast Extract agar. Isolates were identified by colony morphology, Gram staining and biochemical tests. Data were summarized using frequencies, percentages and a 95% confidence interval for culture positivity.
Results
Bacterial growth was detected in 19 of 90 samples, giving an overall contamination rate of 21.1% (95% CI: 14.0%-30.6%). Tap water had the highest positivity at 31.4%, followed by tap swabs at 22.9%. All isolates were Gram-negative bacilli. Pseudomonas aeruginosa predominated, followed by Klebsiella pneumoniae, Escherichia coli and Citrobacter freundii. Legionella pneumophila was not isolated. Reverse osmosis, air-conditioning and drinking water samples showed no growth. Contamination was concentrated at distal tap outlets, identifying potential environmental reservoirs.
Conclusion
Hospital water outlets, especially taps, were important environmental points for microbial contamination. Routine surveillance, timely maintenance and point-of-use infection control measures are essential to reduce water-associated infection risk.
Recommendations
Hospitals should implement structured water-safety monitoring, periodic flushing, tap outlet disinfection, documentation of corrective actions and integration of water surveillance with infection control audits.
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Copyright (c) 2026 Dr. Bidanchi Ch Marak, Dr. S Ruth Ramya, Dr. Aditi Tomer Thakur, Dr. Taruni, Dr. R Kondal Rao, Sultana Nadera, Dr. Nagasaikaran Sade
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