Molecular epidemiology of a nationwide Pseudomonas aeruginosa outbreak in Norway reveals multiple distinct clusters, including high-risk clone ST244

IF 3.1 3区医学 Q1 INFECTIOUS DISEASES

Journal of Hospital Infection Pub Date : 2026-02-01 Epub Date: 2025-11-19 DOI:10.1016/j.jhin.2025.11.004

T. Pedersen , A. Hesselberg Løvestad , A. Ingebretsen , D.H. Skutlaberg , C.G. Ås , A. Blomfeldt

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引用次数: 0

Abstract

Background

A nationwide collection of Pseudomonas aeruginosa bacteraemia isolates was assembled during a wild-type P. aeruginosa ST3875 outbreak affecting approximately 400 patients across 40 hospitals in Norway in 2021–2022.

Aim

To investigate the molecular epidemiology of P. aeruginosa in Norway through a multi-centre retrospective study.

Methods

All available isolates collected over 18 months were retrieved from 20 microbiology laboratories, and underwent whole-genome sequencing at five university hospitals. Metadata, including demographics, sampling dates and locations, were collated. Phylogenetic and comparative genomic analyses were performed to identify sequence types (STs), clusters, resistance determinants, and virulence factors.

Findings

This study included 376 unique patients with P. aeruginosa bacteraemia from 33 hospitals (69% male; median age 76 years), representing >90% of the national catchment area. Incidence varied regionally (5.1–16.3 per 100,000). The ST was resolved for 362 isolates, revealing 164 distinct types. Global high-risk and epidemic clones (e.g. ST233, ST244, ST277, ST298, ST308) comprised 30% of the collection. None of the isolates carried carbapenemases or extended-spectrum β-lactamases. Aside from the ST3875 outbreak clone (N=56), nine unrecognized phylogenetic clusters (two to 20 cases each) spanning multiple hospitals and regions were identified, including a widespread ST244 cluster harbouring a novel genomic island with putative virulence determinants, indicating a selective advantage for dissemination.

Conclusions

This comprehensive genomic surveillance study uncovered multiple unexpected clusters of P. aeruginosa bacteraemia isolates in Norway, along with widespread presence of susceptible epidemic clones. Routine multi-level surveillance integrating sequencing with epidemiological data could enable earlier recognition of emerging high-risk clones and outbreaks, thereby strengthening infection prevention efforts.

查看原文本刊更多论文

挪威全国铜绿假单胞菌暴发的分子流行病学揭示了多个不同的聚集性，包括高风险克隆ST244。

背景：在2021- 2022年挪威40家医院的铜绿假单胞菌ST3875野生型爆发期间，收集了全国范围内的铜绿假单胞菌菌血症分离株。目的：通过多中心回顾性研究，探讨挪威铜绿假单胞菌的分子流行病学。方法：从5所大学附属医院的20个微生物实验室收集18个月以上的分离株，并进行全基因组测序。元数据，包括人口统计，采样日期和地点，被整理。进行了系统发育和比较基因组分析，以确定序列类型（STs）、簇、抗性决定因素和毒力因子。研究结果：我们纳入了来自33家医院的376例独特的铜绿假单胞菌菌血症患者（69%为男性，中位年龄76岁），占全国集水区的90%。发病率因地区而异（5.1-16.3 / 10万）。分离得到362株分离株，共分离出164种不同类型。全球高风险和流行克隆（如ST233、ST244、ST277、ST298、ST308）占收集量的30%。没有分离物携带碳青霉烯酶或广谱β-内酰胺酶。除了ST3875暴发克隆（N = 56）外，还发现了跨越多个医院和地区的9个未被识别的系统发育集群（每个集群2-20例），包括广泛存在的ST244集群，其中包含一个具有假定毒力决定因素的新基因组岛，表明传播具有选择优势。结论：这项全面的基因组监测研究在挪威发现了多个意想不到的铜绿假单胞菌菌血症分离群，以及广泛存在的易感流行克隆。将测序与流行病学数据相结合的常规多层次监测可使早期识别新出现的高风险克隆和疫情，从而加强感染预防工作。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Journal of Hospital Infection 医学-传染病学

CiteScore

12.70

自引率

5.80%

发文量

271

审稿时长

19 days

期刊介绍： The Journal of Hospital Infection is the editorially independent scientific publication of the Healthcare Infection Society. The aim of the Journal is to publish high quality research and information relating to infection prevention and control that is relevant to an international audience. The Journal welcomes submissions that relate to all aspects of infection prevention and control in healthcare settings. This includes submissions that: provide new insight into the epidemiology, surveillance, or prevention and control of healthcare-associated infections and antimicrobial resistance in healthcare settings; provide new insight into cleaning, disinfection and decontamination; provide new insight into the design of healthcare premises; describe novel aspects of outbreaks of infection; throw light on techniques for effective antimicrobial stewardship; describe novel techniques (laboratory-based or point of care) for the detection of infection or antimicrobial resistance in the healthcare setting, particularly if these can be used to facilitate infection prevention and control; improve understanding of the motivations of safe healthcare behaviour, or describe techniques for achieving behavioural and cultural change; improve understanding of the use of IT systems in infection surveillance and prevention and control.