Drivers and multi-modal containment of hospital-acquired multi-drug-resistant bacterial outbreaks: a systematic...

The aims of this study were to delineate the epidemiological trends of hospital-acquired multi-drug-resistant organism (MDRO) outbreaks, identify risk clusters and contributing factors, and evaluate the synergistic efficacy of multi-modal containment strategies.

A systematic literature search was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines across PubMed, Embase, Web of Science, Scopus, and the Cochrane Library up to July 2025. Original reports of bacterial MDRO-related nosocomial outbreaks in inpatient settings were included. Methodological quality and risk of bias were rigorously assessed via non-randomized studies. A multiple correspondence analysis was used to explore risk factor co-occurrence, and UpSet plot was used to visualize the combinatorial efficacy of infection control measures.

Outbreaks analysed in 125 studies from 1995 to 2023 occurred predominantly in intensive care and neonatal units, showing distinct urban clustering, with bacteria resistant to carbapenem and Gram-negative pathogens as the primary threat. Outbreaks stemmed from synergistic failures involving invasive procedures, system saturation, and environmental reservoirs. Control was invariably multi-modal. Universal measures (100.0%, N = 125/125) included contact isolation and hand hygiene. The main intervention pattern (21.6%, N = 27/125) comprised a core of six components including training, cleaning, homology analysis, and rational antibiotic use. A broader bundle containing nine components (18.4%, N = 23/125) added personal protection, equipment management, and environmental surveillance. Ward closure was the definitive strategy for refractory outbreaks.

This hierarchical framework for managing hospital-acquired MDRO outbreaks may facilitate precision intervention, from fundamental bundles to targeted escalation, providing a robust clinical template for optimizing nosocomial infection control.