"We were surprised by the initially high bacterial counts," says Bova. Study results showed Legionella bacteria levels between 0 and 3,000 bacterial colony forming units per milliliter of water from electronic faucet samples.
High Legionella and overall bacterial counts were detected in tests of the newer faucets after the hospital's water flow from the city was briefly interrupted for a few hours before and immediately after the study began. The double interruptions produced a fresh influx of Legionella and other bacteria, requiring Bova and his staff to perform additional disinfecting water treatments, prompting the latest study investigation.
As part of the study, Bova and his team disassembled four of the electronic faucets and their component parts, two before the water was treated and two afterward, with swab culture tests showing Legionella and other bacteria on all of the main component valves and other parts, very few of which, if any, exist in manual faucets.
"Our findings show us that standard hospital water treatment practices are not effective at disinfecting these more complex, electronic-eye faucets of Legionella and other potentially harmful bacteria, even after remediation and additional treatment," says Bova, who has reported his findings to the faucet manufacturer, the Chicago Faucet Co., in Des Plaines, Ill. "We would have to take apart, clean and disinfect the entire faucet assembly, every time, which is simply not practical or cost-effective."
Among the study team's other observations were that the electronic faucets were used continuously, between seven and 110 times per day. Such continuous flushing, says Sydnor, helps suppress bacterial growth.
"It's good for infection control purposes that s
|Contact: David March|
Johns Hopkins Medical Institutions