Nosocomial outbreak due to a novel sequence type of carbapenem-resistant Acinetobacter seifertii

• Published in: American journal of infection control 2024-11
• Main Authors: Barth, Patricia Orlandi, Pereira, Dariane Castro, de Oliveira, Gabriela Simões, Konkewicz, Loriane Rita, Lutz, Larissa, Matos, William Latosinski, Mott, Mariana Preussler, Constante, Caroline Collioni, Wilhelm, Camila Morschbacher, Antochevis, Laura Czekster, Paiva, Rodrigo Minuto, Tragnago, Kellen Figueira, Barth, Afonso Luis, Martins, Andreza Francisco
• Format: Article
• Language: English
• Subjects: Infectious disease outbreaks; NDM-1 beta-lactamase; Plasmid
• ISSN: 0196-6553; 1527-3296; 1527-3296
• DOI: 10.1016/j.ajic.2024.11.019

Acinetobacter seifertii, a member of A baumannii-calcoaceticus complex, can be considered a pathogen of concern due to the presence of resistance genes. The aim of the study was to describe an outbreak of carbapenem-resistant A seifertii among neonates admitted to the neonatal intensive care unit (NICU) at a tertiary care hospital. All patients with carbapenem-resistant A seifertii diagnosed and admitted to the NICU from June 2023 to October 2023 were included. The presence of carbapenemase genes (blaIMP, blaVIM, blaNDM, blaKPC, blaGES, blaOXA-48-like, and blaOXA-23) was investigated by qPCR. Whole-genome sequencing (WGS) was performed by MiSeq (Illumina) and MinION (Nanopore) platforms. Fourier-transform infrared spectroscopy (IR Biotyper) was applied for microbial strain typing. Eleven patients were affected and a set of measures were implemented at NICU to reduce the risk of transmission. The isolates exhibited identical resistance patterns; additionally, all isolates presented the blaNDM-1 gene and were grouped in the same cluster by IR Biotyper. The WGS revealed that the isolates belonged to a novel ST assigned as ST2712, and the blaNDM-1 was carried by the same plasmid type. Our study has identified a novel strain of A seifertii carrying blaNDM-1 responsible for the outbreak, indicating its emergence in the institution. This is the first report of carbapenem-resistant A seifertii ST2712. The use of WGS for genomic surveillance allowed understanding the dissemination of Carbapenem-resistant A baumannii, which is crucial in outbreak scenarios. •First documentation of ST2712 carbapenem-resistant Acinetobacter seifertii blaNDM-1 carrying.•Outbreak involved 11 patients hospitalized at neonatal intensive care unit.•Resistome analyses showed a plasmid harboring blaNDM and other resistance genes.