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Published on: March 17, 2023
Environmental Contamination of Contact Precaution and Non-Contact Precaution Patient Rooms in Six Acute Care
Windy D Tanner1,2, Molly K Leecaster1,2, Yue Zhang1
1Division of Epidemiology, University of Utah, Salt Lake City, Utah, USA.
Background:
Environmental contamination is an important source of hospital multidrug-resistant organism (MDRO) transmission. Factors such as patient MDRO contact precautions (CP) status, patient proximity to surfaces, and unit type likely influence MDRO contamination and bacterial bioburden levels on patient room surfaces. Identifying factors associated with environmental contamination in patient rooms and on shared unit surfaces could help identify important environmental MDRO transmission routes.
Methods:
Surfaces were sampled from MDRO CP and non-CP rooms, nursing stations, and mobile equipment in acute care, intensive care, and transplant units within 6 acute care hospitals using a convenience sampling approach blinded to cleaning events. Precaution rooms had patients with clinical or surveillance tests positive for methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, carbapenem-resistant Enterobacteriaceae or Acinetobacter within the previous 6 months, or Clostridioides difficile toxin within the past 30 days. Rooms not meeting this definition were considered non-CP rooms. Samples were cultured for the above MDROs and total bioburden.
Results:
Overall, an estimated 13% of rooms were contaminated with at least 1 MDRO. MDROs were detected more frequently in CP rooms (32% of 209 room-sample events) than non-CP rooms (12% of 234 room-sample events). Surface bioburden did not differ significantly between CP and non-CP rooms or MDRO-positive and MDRO-negative rooms.
Conclusions:
CP room surfaces are contaminated more frequently than non-CP room surfaces; however, contamination of non-CP room surfaces is not uncommon and may be an important reservoir for ongoing MDRO transmission. MDRO contamination of non-CP rooms may indicate asymptomatic patient MDRO carriage, inadequate terminal cleaning, or cross-contamination of room surfaces via healthcare personnel hands.
Insights
Hospital rooms with contact precautions (CP) show higher multidrug-resistant organism (MDRO) contamination. However, non-CP rooms also harbor MDROs, highlighting potential transmission risks from overlooked environmental reservoirs.
Area of Science:
- Infection Control
- Environmental Microbiology
- Hospital Epidemiology
Background:
- Environmental contamination is a key factor in hospital-acquired multidrug-resistant organism (MDRO) transmission.
- Patient contact precautions (CP) status, room proximity to surfaces, and unit type influence MDRO levels on surfaces.
- Understanding environmental contamination is crucial for identifying MDRO transmission routes.
Purpose of the Study:
- To identify factors associated with environmental contamination in patient rooms and shared unit surfaces.
- To assess the prevalence of MDROs on surfaces in relation to patient CP status.
- To investigate potential reservoirs for MDRO transmission within hospital environments.
Main Methods:
- Surface samples were collected from CP and non-CP rooms, nursing stations, and mobile equipment across different hospital units.
- Sampling utilized a convenience approach, blinded to cleaning events.
- Samples were cultured for specific MDROs (MRSA, VRE, CRE, Acinetobacter, C. difficile) and total bacterial bioburden.
Main Results:
- Approximately 13% of all sampled rooms showed contamination with at least one MDRO.
- MDROs were detected significantly more often in CP rooms (32%) compared to non-CP rooms (12%).
- No significant difference in surface bioburden was observed between CP and non-CP rooms or MDRO-positive and negative rooms.
Conclusions:
- While CP room surfaces are more frequently contaminated, non-CP room surfaces are also commonly contaminated.
- Non-CP room contamination may serve as a reservoir for MDRO transmission, potentially due to asymptomatic carriage or inadequate cleaning.
- Cross-contamination via healthcare personnel hands is a possible pathway for MDRO spread to non-CP room surfaces.
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