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Assessment of the Overall and Multidrug-Resistant Organism Bioburden on Environmental Surfaces in Healthcare Facilities

  • Alicia M. Shams (a1), Laura J. Rose (a1), Jonathan R. Edwards (a1), Salvatore Cali (a2), Anthony D. Harris (a3), Jesse T. Jacob (a4), Anna LaFae (a4), Lisa L. Pineles (a3), Kerri A. Thom (a3), L. Clifford McDonald (a1), Matthew J. Arduino (a1) and Judith A. Noble-Wang (a1)...



To determine the typical microbial bioburden (overall bacterial and multidrug-resistant organisms [MDROs]) on high-touch healthcare environmental surfaces after routine or terminal cleaning.


Prospective 2.5-year microbiological survey of large surface areas (>1,000 cm2).


MDRO contact-precaution rooms from 9 acute-care hospitals and 2 long-term care facilities in 4 states.


Samples from 166 rooms (113 routine cleaned and 53 terminal cleaned rooms).


Using a standard sponge-wipe sampling protocol, 2 composite samples were collected from each room; a third sample was collected from each Clostridium difficile room. Composite 1 included the TV remote, telephone, call button, and bed rails. Composite 2 included the room door handle, IV pole, and overbed table. Composite 3 included toileting surfaces. Total bacteria and MDROs (ie, methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci [VRE], Acinetobacter baumannii, Klebsiella pneumoniae, and C. difficile) were quantified, confirmed, and tested for drug resistance.


The mean microbial bioburden and range from routine cleaned room composites were higher (2,700 colony-forming units [CFU]/100 cm2; ≤1–130,000 CFU/100 cm2) than from terminal cleaned room composites (353 CFU/100 cm2; ≤1–4,300 CFU/100 cm2). MDROs were recovered from 34% of routine cleaned room composites (range ≤1–13,000 CFU/100 cm2) and 17% of terminal cleaned room composites (≤1–524 CFU/100 cm2). MDROs were recovered from 40% of rooms; VRE was the most common (19%).


This multicenter bioburden summary provides a first step to determining microbial bioburden on healthcare surfaces, which may help provide a basis for developing standards to evaluate cleaning and disinfection as well as a framework for studies using an evidentiary hierarchy for environmental infection control.

Infect Control Hosp Epidemiol 2016;1426–1432


Corresponding author

Address correspondence to Alicia M. Shams, 1600 Clifton Rd NE, MS: C-16, Atlanta, GA 30329 (


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Assessment of the Overall and Multidrug-Resistant Organism Bioburden on Environmental Surfaces in Healthcare Facilities

  • Alicia M. Shams (a1), Laura J. Rose (a1), Jonathan R. Edwards (a1), Salvatore Cali (a2), Anthony D. Harris (a3), Jesse T. Jacob (a4), Anna LaFae (a4), Lisa L. Pineles (a3), Kerri A. Thom (a3), L. Clifford McDonald (a1), Matthew J. Arduino (a1) and Judith A. Noble-Wang (a1)...


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