Authors provide four-step disinfection system evaluation process
Legionnaires’ disease outbreaks, caused by Legionella in hospital drinking water, can be prevented using the right disinfection methods. A research review paper, “Controlling Legionella in Hospital Drinking Water: An Evidence-Based Review of Disinfection Methods,” published in Infection Control and Hospital Epidemiology, gives decision makers standard criteria to evaluate and choose the most effective Legionella disinfection methods for their facilities.
Legionella experts and authors Yusen E. Lin, PhD, MBA, National Kaohsiung Normal University, Kaohsiung, Taiwan; Janet E. Stout, PhD, director of Special Pathogens Laboratory and University of Pittsburgh Swanson School of Engineering; and Dr. Victor L. Yu, University of Pittsburgh, rate the efficacy of systemic disinfection, focal disinfection and short-term disinfection methods used in outbreak situations. They offer a four-step approach to assist hospitals in choosing the most effective method.
Choosing the right method or combination of methods reduces the risk of patients contracting Legionnaires’ disease. Stout and her colleagues strongly recommend that infection control practitioners lead the environment of care team in choosing the best disinfection methodology. They also advocate for scheduled routine monitoring through culturing to ensure safe water.
Common Legionella disinfection methods include: copper-silver ionization, chlorine dioxide, monochloramine, ultraviolet light and hyperchlorination (systemic disinfection); point-of-use filtration (focal disinfection); and superheat-and-flush with or without hyperchlorination (short-term disinfection methods in outbreak situations).
Hyperchlorination or heat-and-flush often are used during an outbreak, but are the least effective, the authors found, but copper-silver ionization fulfilled the four-step criteria for demonstrating efficacy.
The author’s four-step evaluation process of disinfection systems includes ensuring the technology kills Legionella. This step is followed by a review of anecdotal experience for controlling Legionella contamination in hospitals, followed by literature review of peer-reviewed and published reports of controlled studies of years of efficacy for hospital-acquired Legionnaires’ disease.