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

Abstract

OBJECTIVE To determine the typical microbial bioburden (overall bacterial and multidrug-resistant organisms [MDROs]) on high-touch healthcare environmental surfaces after routine or terminal cleaning. DESIGN Prospective 2.5-year microbiological survey of large surface areas (>1,000 cm2). SETTING MDRO contact-precaution rooms from 9 acute-care hospitals and 2 long-term care facilities in 4 states. PARTICIPANTS Samples from 166 rooms (113 routine cleaned and 53 terminal cleaned rooms). METHODS 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. RESULTS 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%). CONCLUSIONS 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.

Genomic Analysis of Hospital Plumbing Reveals Diverse Reservoir of Bacterial Plasmids Conferring Carbapenem Resistance

“…For comparison, a 2.5-year multicenter prospective survey of high-touch surfaces in patient rooms found that~40% of the rooms examined were contaminated with MDROs, including Gram-positive and Gram-negative organisms such as vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus, MDR K. pneumoniae, and MDR A. baumannii. We did not investigate Gram-positive organisms in this study; furthermore, WGS was not used to investigate genetic relatedness in that study, so the possible comparisons of studies are limited (56).…”

Preventing Transmission of Multidrug-Resistant Pathogens in the Intensive Care Unit

“…56 The viability of resistant organisms on fomites in the hospital environment is estimated from experimental studies, but is likely affected by many confounding factors (eg, organism burden and strain, temperature, moisture). Some resistant nosocomial pathogens are notoriously hardy on dry surfaces, including VRE and MRSA.…”

Comparison of nylon-flocked swab and cellulose sponge methods for carbapenem-resistant Enterobacteriaceae and gram-negative organism recovery from high-touch surfaces in patient rooms

“…a composite). 4,6 Due to right hand dominance, bacteria may have been more likely to be removed from that side of the HTS during cleaning. To avoid introducing a systematic bias, alternating sides of the HTS were sampled by each method.…”

“…5,6 Identification and antimicrobial susceptibility testing of recovered organisms were performed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (Bruker Daltonics Inc.) and via the BD Phoenix™ Automated Microbiology System, respectively. 4 Enterobacteriaceae resistant to at least ertapenem were identified as CRE.…”