Healthcare microenvironments define multidrug-resistant organism persistence

Area of Science:

• Microbiology
• Environmental Science
• Infectious Disease Epidemiology

Background:

• Multidrug-resistant organisms (MDROs) in healthcare environments are linked to healthcare-associated infections (HAIs), increasing patient morbidity and mortality.
• Understanding the spatial distribution of MDROs is crucial for infection control.

Purpose of the Study:

• To investigate the relationship between patient location, wastewater sites, and bacterial contamination by persistent MDROs in hospital rooms.
• To identify environmental 'hot spots' for MDRO colonization.

Main Methods:

• A prospective cohort study involving 51 hospital rooms with patients carrying eligible MDROs.
• Systematic environmental sampling, MDRO culturing, and 16S rRNA sequencing for microbiome analysis.

Main Results:

• Resistant gram-negative bacteria (Enterobacterales, *Acinetobacter* spp., *Pseudomonas* spp.) were more prevalent farther from patients.
• *Clostridioides difficile* and methicillin-resistant *Staphylococcus aureus* (MRSA) were more common near patients.
• Specific MDROs showed enrichment in certain areas despite widespread bacterial DNA, suggesting factors influencing persistence.

Conclusions:

• MDRO hot spots are influenced by proximity to patients and wastewater sources.
• Analyzing MDRO enrichment relative to bacterial DNA aids in identifying critical micro-environments.
• Targeted cleaning and design strategies can potentially mitigate MDRO persistence and reduce infection risks.