Under the Microscope with Bill Rutala: Microbial Bioburden in Inpatient and Outpatient Areas Beyond Patient Hospital Rooms

Author: Dr. William A. Rutala, PhD, MPH, CIC

Categories: General Infection Prevention, Surface Disinfection & UVC March 14, 2022
Environmental Services Wiping Bathroom

Microbial bioburden of inpatient and outpatient areas beyond patient hospital rooms authored by Cadnum JL, Peralmutter BS, Jencson AL, Haydar H, Hecker MT, Ray AJ, Tomas ME, Saade EA, Donskey CJ.

The contaminated surface environment in hospitals plays an important role in the transmission of several key healthcare-associated pathogens including methicillin-resistant S. aureus (MRSA), vancomycin-resistant enterococci (VRE), Acinetobacter, norovirus, and C. difficile. All these pathogens have been demonstrated to persist in the environment for days (in some cases months), frequently contaminate the environmental surfaces in rooms of colonized or infected patients,  transiently colonize the hands of healthcare personnel, be transmitted by healthcare personnel, and cause outbreaks in which environmental transmission was deemed to play a role.  In contrast to data on contamination of surfaces in inpatient rooms, there is relatively little information about the presence of healthcare pathogens outside the patient rooms.   In this study, the investigators evaluated the microbial burden of bacterial pathogens (MRSA, VRE, C. difficile, and gram-negative bacilli) and Candida spp. on surfaces in four Cleveland area hospitals, 4 outpatient clinics, and 1 surgery center.

An environmental assessment was performed via 3 point-prevalence surveys in each facility using cellulose sponges. In hospitals, high-touch surfaces were sampled from radiology, physical therapy, portable equipment, emergency departments, waiting rooms, subspecialty clinics, and endoscopy facilities. In outpatient facilities, surfaces were sampled in exam rooms including patient and provider areas, patient bathrooms, and waiting rooms, and from portable equipment.

In the hospitals, 9.4% (110/1,195) sites were positive for 1 or more bacteria pathogens and 5.9% (70/1,195) were positive for Candida spp. For the composite of bacterial pathogens, the waiting rooms had the highest frequency of contamination (14.2%) and the clinics were the least contaminated (4.7%).  Based on fluorescent marker removal, <40% of the sites assessed had been cleaned in the previous 24 hours.

In outpatient facilities, 6.4% (31/485) sites were positive for 1 or more bacterial pathogens and 10.3% (50/485) were positive for Candida spp. The percentage of contaminated surfaces for the composite of bacterial pathogens in the outpatient clinics was lowest for clinic 4 and the surgery center (1.9% and 2.0%) and highest in clinic 1 (15.4%). Interestingly, the percentage of fluorescent marker removal was substantially higher in surgery and clinic 4 (82.5%, 63.6%) compared to clinic 1 (7.4%). Based on the fluorescent marker removal from surfaces, cleaning procedures were variable and suboptimal in the areas evaluated.

Surfaces in hospitals outside patient rooms and in outpatient facilities were frequently contaminated with healthcare-associated pathogens. This highlights the need for continued  Improvements in disinfection practices to reduce microbial contamination.

Disclosure: Dr. Rutala is a consultant for PDI.
Cadnum JL, Peralmutter BS, Jencson AL, Haydar H, Hecker MT, Ray AJ, Tomas ME, Saade EA, Donskey CJ. Microbial bioburden in inpatient and outpatient areas beyond patient hospital rooms. Infect Control Hosp Epidemiol 2021 Jul 23;1-5. do: 10.1017/ice.2021.309


Dr. William A. Rutala, PhD, MPH, CIC PhD, MPH, CIC
Dr. William Rutala PhD, MPH, CIC Professor in the Division of Infectious Diseases and Director, Statewide Program for Infection Control and Hospital Epidemiology (SPICE).


Dr. Bill Rutala is the Director and co-founder of the Statewide Program for Infection Control and Epidemiology and a Professor for the Division of Infectious Diseases at the University of North Carolina’s School of Medicine.  He was the Director of Hospital Epidemiology, Occupational Health and Safety Program at the University of North Carolina Hospitals for 38 years before retiring in May 2017.

He is a retired Colonel with the U.S. Army Reserve and is certified in infection control.  He has been an advisor to the Centers for Disease Control and Prevention (a former member of the Healthcare Infection Control Practices Advisory Committee [HICPAC], 1999-2003), the Food and Drug Administration (a former member of the General Hospital and Personal Use Devices Panel), the U.S. Environmental Protection Agency (a member of the Scientific Advisory Panel on Antimicrobial Research Strategies for Disinfectants) and the Federal Trade Commission.  Dr. Rutala is a member of various committees on the local, state, national, and international level as well as several professional societies including the American Society for Microbiology, Association for Professionals in Infection Control and Epidemiology (APIC), and the Society of Healthcare Epidemiology of America (SHEA).  He has served or currently serves on the three peer-reviewed journals on infection prevention in the world (i.e., Infection Control and Hospital Epidemiology, American Journal of Infection Control, and The Journal of Hospital Infection)

He has more than 650 publications (peer-review articles, books, book chapters, brief reports) in the fields of disinfection and sterilization (to include several guidelines such as the CDC Guideline for Disinfection and Sterilization in Healthcare Facilities) and epidemiology and prevention of healthcare-associated infections. Dr. Rutala has also been an invited lecturer at over 400 states, national and international conferences (in over 40 states and 40 countries) and has testified twice before the U.S. Congress.  Dr. Rutala earned his Bachelor of Science degree in science from Rutgers University, his master’s degree in microbiology from the University of Tennessee, and both his master’s in public health and a doctorate in microbiology from the University of North Carolina School of Public Health.

His contributions to infection prevention have been acknowledged by professional organizations with the following awards:  Carole M. DeMille Lifetime Achievement Award (APIC, 1999), Lowbury Lecture (Healthcare Infection Society, Scotland, 2002), Hygiene Medal (Rudolf Schulke Foundation, Germany, 2013), Larson Lectureship Award (APIC, 2012), SHEA Lectureship (SHEA, 2012), Barr Distinguished Alumni Award (UNC School of Public Health, 2012), Kelsey Lecture (the United Kingdom, 2001 and 2012), Crawford Award (lifetime achievement, OSAP, 2008), and Favero Lectureship (APIC, 2009). Dr. Rutala has a “named” award in his honor from two international infection prevention professional societies …APIC (William A. Rutala Research Award) and SHEA (William A. Rutala Scholarship).

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