An outbreak of multi-drug-resistant Acinetobacter baumannii on a burns ICU and its control with multi-faceted containment measures

Abstract

BackgroundPatients in burn centres are at high risk of acquiring multidrug-resistant pathogens due to reduced skin barrier and long hospital stay. MethodsWe report the investigation and control of an outbreak due to multidrug-resistant Acinetobacter baumannii in a burn centre. The 27 patients hospitalized in the centre during the outbreak were regularly screened and a total of 132 environmental samples were performed to identify a potential source. Fourier-transform infrared (FT-IR) spectroscopy and multilocus sequence typing (MLST) were applied to characterise the outbreak strain. ResultsBetween August and November 2022, the outbreak affected eight patients with eleven infections and three potentially related fatal outcomes. An interdisciplinary and multiprofessional outbreak team implemented a bundle strategy with repetitive admission stops, isolation precaution measures, patient screenings, enhanced cleaning and disinfection, and staff education. FT-IR spectroscopy suggested that the outbreak started from an index patient, who was repatriated one month before from a country with high prevalence of MDR A. baumannii. Environmental sampling did not identify a common source. Acquisition of the outbreak strain was associated with larger burn lesions ≥ 2a (per percent increase odds ratio (OR) 1.05 (0.99-1.12), P=0.09), and inversely associated with a higher nurse-to-patient ratio (per 0.1 increase OR 0.34, 95%CI 0.10-1.12, P=0.06). ConclusionsBurn patients with a large area of affected body surface, are at high risk for colonization and infection due to MDRO, particularly during periods of high workload. A multifaceted containment strategy can successfully control outbreaks due to MDR A. baumannii in a burn centre.