A multilayered infection control intervention on carbapenem-resistant Acinetobacter baumannii acquisition: An interrupted time series

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB) causes life-threating hospital-acquired. Due to a limited number of Intensive-Care-Unit (ICU) beds, these patients are often treated in high-dependency (HD) non-ICUs within internal-medicine wards (IMW) in Israel. We aimed to assess the effectiveness of a multilayered infection-control intervention on CRAB infection rate in IMWs, especially in its HD non-ICUs with ongoing CRAB transmission. Methods: A quasi-experimental, before-and-after, interrupted time-series study with control outcomes. We conducted a multilayered intervention over 3.5 years, which included 4 phases: (1) Pre intervention; (2) Intervention introduction: introduced enhanced environment cleaning; (3) Intervention phase 1: introduced active surveillance; (4) Intervention phase 2: introduced CRAB-positive patient cohorting, in addition to previous ongoing measures taken. Results: CRAB was isolated from 204 patients aged 69.8y/o ± 15.86y, 59.8% male, 34.3% had CRAB-positive clinical samples. Mean hospital length-of-stay was 30.5 days, with a 30-day postdischarge mortality rate of 55.9%. Mean CRAB clinical cases decreased from 0.89 in preintervention to 0.11 at the end of phase 2, with a change in slope and level after the intervention of P = .02 (CI: − 0.204 to − 0.040) and P = .004 (CI: − 0.013 to − 0.003), respectively. Conclusions: This intervention, including enhanced environment cleaning, active surveillance, and patient cohorting, successfully reduced CRAB acquisition in IMWs and their HD non-ICUs.