ISTC’s Institutional Water Treatment (IWT) program offers water source testing for Legionella pneumophila, the bacterium that causes Legionnaires’ disease. IWT is one of only a few laboratories within Illinois that is CDC ELITE Certified for Legionella testing. The CDC Environmental Legionella Isolation Techniques Evaluation (ELITE) is a yearly program where laboratories demonstrate their proficiency in successfully identifying Legionella in water samples.
What is Legionella pneumophila?
L. pneumophila is a pathogenic bacterium that can grow in engineered water systems, such as showerheads, sink faucets, cooling towers, ice machines, spas (hot tubs), therapy pools, fountains, evaporative condensers, hot water systems, and complex water distribution systems.
When L. pneumophila is inhaled through water aerosols or is aspirated from contaminated water, it can cause Legionnaires’ disease, a serious, potentially fatal type of pneumonia, and Pontiac fever, a flu-like illness.
Why conduct Legionella testing?
New regulations and standards have prioritized the development of water management programs to minimize the growth and spread of Legionella in institutional water systems. Regular maintenance testing of large distribution water systems provides validation that the water management program is effectively preventing the growth of L. pneumophila. Testing is also performed during outbreak investigations to identify the source of bacteria where reported cases of Legionnaires’ disease have been confirmed.
What type of Legionella testing is offered?
IWT offers on-site water sample collection and two laboratory test methods for L. pneumophila detection.
IDEXX Legiolert® is a bacterial enzyme-substrate reagent that creates a liquid culture when added to potable and non-potable samples. Legiolert uses an added substrate to produce a brown color indicator when L. pneumophila is present and has a faster incubation time of 7 days instead of the standard culture method of 10 days.
Standard microbial spread plate culture is an agar-based method for potable and non-potable samples. Samples are membrane-filtered and treated with an acid buffer before using the spread plate method on BYCE selective agar plates and incubating. BCYE±cys agar is used for confirmation when colonies appear on BYCE selective agar. The incubation time for this method is 10 days.
For additional information, please contact:
Don Kueneke ꟾ 217-333-3659 OR Ashley DiVincenzo ꟾ 217-333-9813
Download the Legionella pneumophila Testing flyer.
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