Retrospective Analysis of the Molecular Links Among Clustered Cases of Acinetobacter baumannii Nosocomial Infections Occurring in Different Years within the ICU — Jiangsu Province, China, 2016–2021

What is already known about this topic?: (CRAB) is a well-established cause of difficult-to-treat nosocomial infections, particularly in intensive care units (ICUs). This strain is known for its ability to persist in hospital environments, leading to outbreaks. What is added by this report?: This retrospective study analyzed five separate CRAB nosocomial infection clusters that occurred in 2016, 2019, and 2021. This revealed the molecular epidemiological links between cases and environmental samples across different years, suggesting the potential for ongoing environmental transmission. Following intensive terminal disinfection, no homologous pathogens have been detected since 2021. What are the implications for public health practice?: The potential risk of environmental transmission suggests that the current bedside isolation strategies may have deficiencies. Given that the prevailing ICU multibedroom configuration remains unchanged, additional effective disinfection methods must be developed urgently. These techniques should specifically target high-touch irregular surfaces to disrupt persistent CRAB transmission.