Dataset Information

The Benefits of Whole Genome Sequencing for Foodborne Outbreak Investigation from the Perspective of a National Reference Laboratory in a Smaller Country.

ABSTRACT: Gradually, conventional methods for foodborne pathogen typing are replaced by whole genome sequencing (WGS). Despite studies describing the overall benefits, National Reference Laboratories of smaller countries often show slower uptake of WGS, mainly because of significant investments required to generate and analyze data of a limited amount of samples. To facilitate this process and incite policy makers to support its implementation, a Shiga toxin-producing Escherichia coli (STEC) O157:H7 (stx1+, stx2+, eae+) outbreak (2012) and a STEC O157:H7 (stx2+, eae+) outbreak (2013) were retrospectively analyzed using WGS and compared with their conventional investigations. The corresponding results were obtained, with WGS delivering even more information, e.g., on virulence and antimicrobial resistance genotypes. Besides a universal, all-in-one workflow with less hands-on-time (five versus seven actual working days for WGS versus conventional), WGS-based cgMLST-typing demonstrated increased resolution. This enabled an accurate cluster definition, which remained unsolved for the 2013 outbreak, partly due to scarce epidemiological linking with the suspect source. Moreover, it allowed detecting two and one earlier circulating STEC O157:H7 (stx1+, stx2+, eae+) and STEC O157:H7 (stx2+, eae+) strains as closely related to the 2012 and 2013 outbreaks, respectively, which might have further directed epidemiological investigation initially. Although some bottlenecks concerning centralized data-sharing, sampling strategies, and perceived costs should be considered, we delivered a proof-of-concept that even in smaller countries, WGS offers benefits for outbreak investigation, if a sufficient budget is available to ensure its implementation in surveillance. Indeed, applying a database with background isolates is critical in interpreting isolate relationships to outbreaks, and leveraging the true benefit of WGS in outbreak investigation and/or prevention.

SUBMITTER: Nouws S

PROVIDER: S-EPMC7466227 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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The Benefits of Whole Genome Sequencing for Foodborne Outbreak Investigation from the Perspective of a National Reference Laboratory in a Smaller Country.

Nouws Stéphanie S Bogaerts Bert B Verhaegen Bavo B Denayer Sarah S Crombé Florence F De Rauw Klara K Piérard Denis D Marchal Kathleen K Vanneste Kevin K Roosens Nancy H C NHC De Keersmaecker Sigrid C J SCJ

Foods (Basel, Switzerland) 20200801 8

Gradually, conventional methods for foodborne pathogen typing are replaced by whole genome sequencing (WGS). Despite studies describing the overall benefits, National Reference Laboratories of smaller countries often show slower uptake of WGS, mainly because of significant investments required to generate and analyze data of a limited amount of samples. To facilitate this process and incite policy makers to support its implementation, a Shiga toxin-producing <i>Escherichia coli</i> (STEC) O157:H ...[more]

PMID: 32752159

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Project description:BACKGROUND:High quality diagnostic services are crucial for tuberculosis (TB) diagnosis, treatment and control. A strong laboratory quality management system (QMS) is critical to ensuring the quality of testing and results. Recent initiatives to improve TB laboratory quality have focused on low and middle-income countries, but similar issues also apply to high-income countries. METHODS AND FINDINGS:Using a multipronged approach reviews of facilities, equipment, processes (purchasing, pre-analytic, analytic and post-analytic), staff, health and safety, documentation, information management and organization based on the ISO 15189 and the twelve quality system essentials were conducted between October 2015 and January 2016 at the National TB Reference Laboratory in Germany. Outcome assessment included proportion of smear positive slides, proportion of contaminated liquid cultures and DNA contamination rates before and after implementation of QMS. The odds ratio for these outcomes was calculated using a before/after comparison. Reviews highlighted deficiencies across all twelve quality system essentials and were addressed in order of priority and urgency. Actions aimed at improving analytical quality, health and safety and information management were prioritised for initial implementation in parallel with each other. The odds ratio for a sample to be tested as microscopically positive increased by 2.08 (95%CI 1.41-3.06) comparing the time before with the time after implementation of quality managed fluorescence microscopy. Liquid culture contamination rates decreased from 23.6- 7.6% in April-July 2016 to <10% in November 2017-March 2018. The proportion of negative controls showing evidence of DNA contamination decreased from 38.2% in 2013 to 8.1% in 2017, the corresponding odds ratio was 0.14 (95%CI 0.07-0.29). CONCLUSION:This study showed marked improvement on quality indicators after implementation of a QMS in a National TB Reference Laboratory. The challenges and lessons learned in this study are valuable not just for high-income settings, but are equally generalizable to other laboratories.

Project description:Next-generation sequencing (NGS) of bacterial genomes has recently become more accessible and is now available to the routine diagnostic microbiology laboratory. However, questions remain regarding its feasibility, particularly with respect to data analysis in nonspecialist centers. To test the applicability of NGS to outbreak investigations, Ion Torrent sequencing was used to investigate a putative multidrug-resistant Escherichia coli outbreak in the neonatal unit of the Mercy Hospital for Women, Melbourne, Australia. Four suspected outbreak strains and a comparator strain were sequenced. Genome-wide single nucleotide polymorphism (SNP) analysis demonstrated that the four neonatal intensive care unit (NICU) strains were identical and easily differentiated from the comparator strain. Genome sequence data also determined that the NICU strains belonged to multilocus sequence type 131 and carried the bla(CTX-M-15) extended-spectrum beta-lactamase. Comparison of the outbreak strains to all publicly available complete E. coli genome sequences showed that they clustered with neonatal meningitis and uropathogenic isolates. The turnaround time from a positive culture to the completion of sequencing (prior to data analysis) was 5 days, and the cost was approximately $300 per strain (for the reagents only). The main obstacles to a mainstream adoption of NGS technologies in diagnostic microbiology laboratories are currently cost (although this is decreasing), a paucity of user-friendly and clinically focused bioinformatics platforms, and a lack of genomics expertise outside the research environment. Despite these hurdles, NGS technologies provide unparalleled high-resolution genotyping in a short time frame and are likely to be widely implemented in the field of diagnostic microbiology in the next few years, particularly for epidemiological investigations (replacing current typing methods) and the characterization of resistance determinants. Clinical microbiologists need to familiarize themselves with these technologies and their applications.

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Dataset Information

The Benefits of Whole Genome Sequencing for Foodborne Outbreak Investigation from the Perspective of a National Reference Laboratory in a Smaller Country.

Publications

The Benefits of Whole Genome Sequencing for Foodborne Outbreak Investigation from the Perspective of a National Reference Laboratory in a Smaller Country.

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