Water Wall in Hospital Dispenses Legionella

Question: When does a decorative water wall, installed in a hospital lobby to provide a calming ambience, become a health risk? Answer: When the water wall dispenses a bacteria-laden mist that results in an outbreak of Legionnaires disease.

Eight people who walked by just such a water wall in a Wisconsin hospital lobby in 2010 are believed to have contracted the disease by inhaling the mist from the streaming water. Legionella can affect people whose immunity may be depressed due to an underlying illness, or due to a medication regimen; smokers may also be vulnerable. One of the patients affected in Wisconsin was a delivery person who had been a smoker and had made two deliveries to the hospital. Others had visited the pharmacy adjacent to the water wall to obtain medications.

The outbreak is an unintended consequence of well-intentioned efforts to create a soothing and welcoming healthcare environment. For now, we know those decorative water walls are a bad idea unless sanitary conditions are meticulously maintained.

Legionella under the Rocks

A new study published in the journal Infection Control and Hospital Epidemiology notes that although the decorative water wall underwent routine cleaning and maintenance, the bacterium Legionella pneumophila found a niche at the base of the water wall. The bacterial breeding ground was identified as a bed of sponge-like foam installed under decorative rocks to prevent water splashing.

In a January 11, 2012 interview with National Public Radio, the study’s lead author, Dr. Thomas Haupt, a respiratory disease epidemiologist for the Wisconsin Division of Public Health, was asked whether chlorine in the water would have prevented the outbreak. Haupt replied that chlorine in the atrium of a hospital “would have caused a lot of smell.” Haupt also described what seems to have been a “perfect storm” for Legionella contamination: Lights installed under the foam material in the trough and the trough’s close proximity to a fireplace helped provide a warm environment highly conducive to Legionella growth.

Haupt’s study notes the Wisconsin outbreak is the second example of Legionnaires disease associated with a decorative fountain in a healthcare setting. (The first example occurred in 2007.) The Wisconsin Department of Public Health has developed interim guidelines advising healthcare facilities with similar water walls or fountains to “establish strict maintenance procedures and conduct periodic bacteriologic monitoring to assess levels of Legionella.”

Fortunately, all eight Wisconsin patients recovered from Legionnaire’s disease and the hospital water trough has been converted into a planter. Going forward, let’s either use the tools we have to keep Legionella in check in decorative water walls, or keep them dry.

Jerod M. Loeb, Ph.D. is Executive Vice President, Healthcare Quality Evaluation at The Joint Commission in Oakbrook Terrace, Illinois.