Researchers at The Johns Hopkins University School of Medicine have determined that electronic faucets are more likely to become contaminated with unacceptably high levels of bacteria, including Legionella spp., compared with traditional manually operated faucets. The study will be presented on Saturday at the annual meeting of the Society for Healthcare Epidemiology of America (SHEA).
Electronic-eye, non-touch faucets have been increasingly utilized in healthcare settings to lower water consumption and in an attempt to reduce recontamination of the hands of healthcare personnel. Emily Sydnor, MD, infectious disease fellow at The Johns Hopkins University School of Medicine, and colleagues, working in conjunction with the facilities and engineering departments at Johns Hopkins Hospital examined bacterial growth from faucets of two clinical wards within the hospital from December 2008 through January 2009. Their study included 20 manual faucets and 20 electronic faucets, each receiving water from the same source.
Cultures obtained from the faucets showed that 50 percent of water cultures from electronic faucets grew Legionella spp. compared to 15 percent of water cultures from manual faucets. Sydnor also found that 26 percent of water cultures from electronic faucets had significant growth on heterotrophic plate count (HPC) cultures, an estimate of the number of bacteria in the water, compared to 13 percent of water cultures from manual faucets. While the HPC rates were not statistically different, Sydnor believes the differences are worth noting.
Additionally, following a flush of the water system using chlorine dioxide the disparity between electronic and manual faucets persisted. After the cleaning, 29 percent of electronic faucet cultures were still contaminated with bacteria compared with seven percent of manual faucet cultures.
Sydnor speculated that the increased bacterial growth in electronic faucets may be due to contamination of the numerous parts and valves that make up the faucet. During the course of collecting water samples, researchers discovered that all of the electronic faucet parts grew Legionella spp.
She explained that the study's findings should not create cause for concern over the use of electronic faucets by the general public. "The levels of bacterial growth in the electronic faucets, particularly the Legionella spp., were of concern because they were beyond the tolerable thresholds determined by the hospital. Exposure to Legionella spp. is dangerous for chronically ill or immune compromised patients because it may cause pneumonia in these vulnerable patients. The levels we found of both Legionella spp. and bacterial burden on HPC were still within the level that is well tolerated by healthy individuals," said Sydnor. Following the study, Johns Hopkins Hospital is replacing electronic faucets in clinical areas with manual faucets, and has decided not to install electronic faucets in clinical areas of its new hospital building now under construction.
Regardless of faucets type, Gordon noted that the importance of proper hand-hygiene practices by healthcare personnel to help reduce transmission of pathogens in healthcare settings should not be marginalized. "Proper hand hygiene practices are a basic and evidence-based element of helping to prevent HAIs."
"As infectious disease experts, our job is to remain vigilant about protecting patients from potential exposure to infection causing agents. This means that no matter how innovative the technology, the benefits must always be weighed against patient protection," said Steven Gordon, MD, president of SHEA.
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