Strategies to prevent cross-transmission of multidrug-resistant microorganisms in intensive care units: A narrative review

• Environmental cleaning in ICUs is a key horizontal strategy to reduce cross-transmission of multidrug-resistant microorganisms. • Gut microbiota modulation (prebiotics, probiotics, synbiotics) represents a novel preventive approach against dysbiosis-related infections. • Multi-modal evaluation methods (visual inspection, fluorescent markers, ATP bioluminescence, microbiological culture) improve assessment of cleaning quality. • Innovative adjunctive technologies (e.g., ultraviolet disinfection) enhance terminal cleaning effectiveness against MDR pathogens. • Strengthening safety culture and continuous ICU staff education ensures sustainability of environmental infection control practices. Organisms’ transmission in intensive care units (ICUs) should be addressed by modulation of the skin and gut microbiome (endogenous) or by acquisition of the environment (exogenous). The microbiome has recently been reported as a reservoir of organisms, modulating the immune host response. Interventions on the gut microbiome are a promising way to prevent the development of hospital-acquired infections in the ICU and reduce the risk of cross-transmission of multidrug-resistant microorganisms. Maintaining the cleanliness of patient care areas is a safety strategy for preventing healthcare-associated infections and recent insights on microbiome modulation to reduce the risk for cross-infection. Evidence indicates that regular cleanliness monitoring can positively influence patient outcomes. The development of standardized cleaning checklists is strongly recommended. Key procedural strategies include preliminary site evaluations to determine the extent of contamination or surface damage, cleaning from low-touch to high-touch areas, and progressing from clean to contaminated regions. Chemical agents such as quaternary ammonium compounds, sodium hypochlorite, and hydrogen peroxide are effective for decontamination. Studies demonstrate a positive correlation between the number of touches a surface receives and its bacterial load, emphasizing the importance of assessing contamination levels and cleaning quality. Such evaluations inform the development of environmental cleaning protocols, guide facility policies, and improve program effectiveness. Cleanliness evaluation monitoring should measure the assessment of cleaning practices and cleanliness levels. Using probiotics, prebiotics, and synbiotics is an innovative strategy to reduce dysbiosis and improve host immunity. Lastly, strengthening staff education is essential to enhancing environmental infection control.