Special Pathogens Laboratory partners with industry and healthcare sectors to evaluate products that detect, treat or control Legionella and other waterborne pathogens, as well as antimicrobial innovations to combat the spread of infection.


SPL validates the efficacy of disinfection methods for Legionella in water systems using a step-wise evaluation criteria. Our approach is published in the Experiences of the First 16 Hospitals Using Copper-silver Ionization: Implications for the Evaluation of Other Disinfection Modalities (2003).

Sanipur Monochloramine

Monochloramine has been used successfully for municipal water treatment. An onsite monochloramine generation system for treatment of single buildings was developed by Sanipur (Brescia, Italy). The results showed a significant decrease in Legionella percent positivity of the hospital's hot water system soon after installation. Dr. Stout presented findings of the first U.S. study of this monochloramine generating system for Legionella disinfection at the annual Association of Water Technologies conference in September 2012.

SPL presented two posters on monochloramine in October 2013 at the Eighth International Conference on Legionella in Australia

Monochloramine Disinfection of a Hospital Water System for Preventing Hospital-Acquired Legionnaires' Disease: Lessons Learned from a 1.5 Year Study presented more data of the first US field study of a monochloramine generating system in a hospital hot water system. The conclusions show monochloramine to be a promising disinfectant for Legionella.

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Use of Pyrosequencing to Determine the Effects of Monochloramine Treatment on Legionella and Associated Bacterial Populations in a Hospital Hot Water System is the first US study to assess changes in Legionella and microbial flora due to chloramination in a hospital's hot water system using next generation sequencing. This study shows a strong reduction in Legionella presence and a lack of many issues with chloramination found in municipal water supplies.

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Nonchemical Water Treatment Devices

The first study of the efficacy of nonchemical treatment devices for controlling microbiological activity (planktonic and sessile) within a pilot scale model cooling tower. Funded by ASHRAE.

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Biological control in cooling water systems using nonchemical treatment devices. HVAC&R Research Scott Duda, Janet E. Stout & Radisav Vidic (2011) HVAC&R Research, 17:5, 872-89.  

Chlorine dioxide

Prospective study of the safety and efficacy of chlorine dioxide for Legionella control in a hospital water system (PDF). Zhang Z, McCann C, Stout JE, et al.  Infection Control and Hospital Epidemiology. 2007; 28(8).


QPoint Filter

Legionella, Pseudomonas aeruginosa, and other opportunistic waterborne pathogens can persist in water distribution systems despite municipal chlorination and secondary disinfection. These organisms can cause healthcare-acquired infections in immunocompromised patients. Point-of-use (POU) filtration can limit exposure to these organisms in high-risk areas of hospitals; however short (31 day) maximum lifetime and membrane clogging can limit their use. SPL collaborated with a Pennsylvania healthcare facility to perform a field evaluation of a new point-of-use faucet filter  (Pall Medical QPoint Tap Water Filter) that was developed to address these limitations. The results were shared at a poster session at APIC 2014 in June.

Evaluation of a New Point-of-Use Faucet Filter for Preventing Legionella and Total Bacteria

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Aquasafe Point of Use Filters

Pall-Aquasafe (Pall Corporation) filters eliminated Legionella pneumophila.

SPL scientists evaluated the efficacy of point-of-use faucet water filters in a hospital building with chronic Legionella contamination. The study showed that Pall-Aquasafe (Pall Corporation) filters eliminated Legionella pneumophila.

Efficacy of new point-of-use filter for preventing exposure to Legionella and waterborne bacteria (PDF). Sheffer PJ, Stout JE, Wagener MM, Muder RR.  American Journal of Infection Control. 2005; 33(5) Suppl. 1: S20-S25.

Real-Time Quantitative PCR

SPL researchers evaluated a novel PCR method for the detection of Legionella in water using the GeneDisc system (Pall Corporation).

Poster PDF: A Rapid Method for the Detection of the Nosocomial Waterborne Pathogens Legionella spp. and Pseudomonas aeruginosa by Real-time Quantitative PCR: A Comparison with Standard Culture. Sue M. Mietzner, Pratima Adhikari, Janet E. Stout, Victor L. Yu (Special Pathogens Laboratory and University of Pittsburgh)


PDISani-Hands® ALC Antimicrobial Alcohol Gel Hand Wipes

Alcohol-Based Wipes Significantly More Effective than Rubs in Reducing Bacteria; Findings Could Impact Hospital-Acquired Infections

SaniPDI Inc. is the Global Leader in pre-moistened wipes for the healthcare industry. SPL researchers evaluated the efficacy of the PDI Sani-Hands® ALC Antimicrobial Alcohol Gel Hand Wipes vs. hand gel and soap.

Special Pathogens Laboratory's study measured the effectiveness of this ethanol wipe against an ethanol rub (Purell®) in eliminating bacteria. Our study shows that wipes-towlettes saturated with alcohol are more effective than popular alcohol-based hand rubs in reducing bacteria from hands. Specifically, PDI Sani-Hands® was significantly more effective than the rub in reducing the number of viable bacteria on hands.

Revisiting the hand wipe versus gel rub debate: Is a higher-ethanol content hand wipe more effective than an ethanol gel rub? (PDF)  D’Antonio NN, Rihs JD, &Stout JE, Yu VL. Am J Infect Control 2010;38 (9):671-758


Antimicrobial Polymer in Keyboard Covers Significantly Reduces

Biosafe, Inc. has a novel antimicrobial polymer, BIOSAFE HM4100 that can be incorporated into a variety of materials, including the polyurethane used to make keyboard covers and other plastics.

SPL performed a study to determine whether plastic keyboard covers compounded with HM4100 effectively minimizes the survival of bacterial species commonly present on environmental surfaces in the healthcare setting. The Biosafe coating demonstrated efficacy in reducing viability for methicillin-resistant staphyloccus aureus (MRSA), Pseudomonas aeruginosa, E. coli, and vancomycin-resistant Enterococcus faecalis (VREF).

Computer Keyboard Covers Impregnated with a Novel Antimicrobial Polymer Significantly Reduce Microbial Contamination (PDF poster). D’Antonio N, Rihs JD, Tosiano M, Stout JE. Association for Professionals in Infection Control and Epidemiology, Inc., Fort Lauderdale, FL, June 2009.