Hospital-based bacterial and fungal outbreaks during the COVID-19 pandemic: a systematic review and meta-analysis

Abstract

Background Pandemics pose extraordinary challenges to health care systems. Breakdowns in infection prevention and control measures during such crises can significantly compromise patient outcomes and facilitate the spread of resistant pathogens. This study aimed to describe the characteristics and impact of bacterial and fungal hospital outbreaks during the COVID-19 pandemic. Methods This systematic review and meta-analysis were conducted in accordance with PRISMA 2020 guidelines and were registered in PROSPERO (CRD42025648727). Results A total of 619 outbreak-related cases were identified (62.9% male; age range: 21-101) in 25 studies. Acinetobacter baumannii was the most frequently reported (n = 320) pathogen with the highest mortality rate (59%), followed by Candida auris (n = 188, 52% mortality). Two-thirds of outbreaks (66.66%) with reported resistance data had all strains multidrug-resistant. Health care worker-related factors, such as a lack of personnel, insufficient training, and increased workload, were mainly cited as contributors to secondary hospital outbreaks. The maintenance of environmental cleaning and disinfection was often prioritized over hand hygiene. Conclusions To prevent secondary hospital outbreaks of multidrug-resistant in the future, infection prevention and control programs should be strengthened with increased staff awareness, sustainable environmental hygiene, and antimicrobial stewardship interventions. These findings should be incorporated into pandemic preparedness frameworks and implemented through multidisciplinary audits to ensure sustainability. Copyright © 2025. Published by Elsevier Inc.