Retrospective analysis of whole genome sequencing compared to prospective typing data in further informing the epidemiological investigation of an outbreak of Shigella sonnei in the UK

2013 ◽  
Vol 141 (12) ◽  
pp. 2568-2575 ◽  
Author(s):  
J. McDONNELL ◽  
T. DALLMAN ◽  
S. ATKIN ◽  
D. A. TURBITT ◽  
T. R. CONNOR ◽  
...  

SUMMARYThe aim of this study was to retrospectively assess the value of whole genome sequencing (WGS) compared to conventional typing methods in the investigation and control of an outbreak of Shigella sonnei in the Orthodox Jewish (OJ) community in the UK. The genome sequence analysis showed that the strains implicated in the outbreak formed three phylogenetically distinct clusters. One cluster represented cases associated with recent exposure to a single strain, whereas the other two clusters represented related but distinct strains of S. sonnei circulating in the OJ community across the UK. The WGS data challenged the conclusions drawn during the initial outbreak investigation and allowed cases of dysentery to be implicated or ruled out of the outbreak that were previously misclassified. This study showed that the resolution achieved using WGS would have clearly defined the outbreak, thus facilitating the promotion of infection control measures within local schools and the dissemination of a stronger public health message to the community.

2020 ◽  
Vol 8 (12) ◽  
pp. 1986
Author(s):  
João Perdigão ◽  
Cátia Caneiras ◽  
Rita Elias ◽  
Ana Modesto ◽  
Anton Spadar ◽  
...  

The evolutionary epidemiology, resistome, virulome and mobilome of thirty-one multidrug resistant Klebsiella pneumoniae clinical isolates from the northern Vila Real region of Portugal were characterized using whole-genome sequencing and bioinformatic analysis. The genomic population structure was dominated by two main sequence types (STs): ST147 (n = 17; 54.8%) and ST15 (n = 6; 19.4%) comprising four distinct genomic clusters. Two main carbapenemase coding genes were detected (blaKPC-3 and blaOXA-48) along with additional extended-spectrum β-lactamase coding loci (blaCTX-M-15, blaSHV-12, blaSHV-27, and blaSHV-187). Moreover, whole genome sequencing enabled the identification of one Klebsiella variicola KPC-3 producer isolate previously misidentified as K. pneumoniae, which in addition to the blaKPC-3 carbapenemase gene, bore the chromosomal broad spectrum β-lactamase blaLEN-2 coding gene, oqxAB and fosA resistance loci. The blaKPC-3 genes were located in a Tn4401b transposon (K. variicolan = 1; K. pneumoniaen = 2) and Tn4401d isoform (K. pneumoniaen = 28). Overall, our work describes the first report of a blaKPC-3 producing K. variicola, as well as the detection of this species during infection control measures in surveillance cultures from infected patients. It also highlights the importance of additional control measures to overcome the clonal dissemination of carbapenemase producing clones.


2018 ◽  
Vol 39 (07) ◽  
pp. 852-860 ◽  
Author(s):  
Sarah M. Bergin ◽  
Balamurugan Periaswamy ◽  
Timothy Barkham ◽  
Hong Choon Chua ◽  
Yee Ming Mok ◽  
...  

OBJECTIVEWe report the utility of whole-genome sequencing (WGS) conducted in a clinically relevant time frame (ie, sufficient for guiding management decision), in managing a Streptococcus pyogenes outbreak, and present a comparison of its performance with emm typing.SETTINGA 2,000-bed tertiary-care psychiatric hospital.METHODSActive surveillance was conducted to identify new cases of S. pyogenes. WGS guided targeted epidemiological investigations, and infection control measures were implemented. Single-nucleotide polymorphism (SNP)–based genome phylogeny, emm typing, and multilocus sequence typing (MLST) were performed. We compared the ability of WGS and emm typing to correctly identify person-to-person transmission and to guide the management of the outbreak.RESULTSThe study included 204 patients and 152 staff. We identified 35 patients and 2 staff members with S. pyogenes. WGS revealed polyclonal S. pyogenes infections with 3 genetically distinct phylogenetic clusters (C1–C3). Cluster C1 isolates were all emm type 4, sequence type 915 and had pairwise SNP differences of 0–5, which suggested recent person-to-person transmissions. Epidemiological investigation revealed that cluster C1 was mediated by dermal colonization and transmission of S. pyogenes in a male residential ward. Clusters C2 and C3 were genomically diverse, with pairwise SNP differences of 21–45 and 26–58, and emm 11 and mostly emm120, respectively. Clusters C2 and C3, which may have been considered person-to-person transmissions by emm typing, were shown by WGS to be unlikely by integrating pairwise SNP differences with epidemiology.CONCLUSIONSWGS had higher resolution than emm typing in identifying clusters with recent and ongoing person-to-person transmissions, which allowed implementation of targeted intervention to control the outbreak.Infect Control Hosp Epidemiol 2018;852–860


2019 ◽  
Vol 95 (1130) ◽  
pp. 686.3-686
Author(s):  
Mark Caulfield

The UK 100,000 Genomes Project has focussed on transforming genomic medicine in the National Health Service using whole genome sequencing in rare disease, cancer and infection. Genomics England partnering with the NHS established 13 Genomic Medicine Centres, the NHS whole genome sequencing centre and the Genomics England Clinical Interpretation Partnership (3337 researchers from 24 countries). We sequenced the 100,000th genome on the 5th December 2019 and completed an initial analysis for participants in July 2019. Alongside these genomes we have assembled a longitudinal life course dataset for research and diagnosis including 2.6 billion clinical data points for the 3000 plus researchers to work on to drive up the value of the genomes for direct healthcare. In parallel we have partnered the NHS to establish one of the world’s most advanced Genomic Medicine Service where we re-evaluated 300,000 genomic tests and upgraded 25% of tests to newer technologies with an annual review. The Department of Health have announced the ambition to undertake 5 million genome analyses over the next 5 years focused on new areas tractable to health gain.


2018 ◽  
Vol 82 (1) ◽  
pp. 30-38 ◽  
Author(s):  
RICHARD ELSON ◽  
ADEDOYIN AWOFISAYO-OKUYELU ◽  
TREVOR GREENER ◽  
CRAIG SWIFT ◽  
ANAÏS PAINSET ◽  
...  

ABSTRACT This article describes the identification and investigation of two extended outbreaks of listeriosis in which crabmeat was identified as the vehicle of infection. Comparing contemporary and retrospective typing data of Listeria monocytogenes isolates from clinical cases and from food and food processing environments allowed the detection of cases going back several years. This information, combined with the analysis of routinely collected enhanced surveillance data, helped to direct the investigation and identify the vehicle of infection. Retrospective whole genome sequencing (WGS) analysis of isolates provided robust microbiological evidence of links between cases, foods, and the environments in which they were produced and demonstrated that for some cases and foods, identified by fluorescent amplified fragment length polymorphism, the molecular typing method in routine use at the time, were not part of the outbreak. WGS analysis also showed that the strains causing illness had persisted in two food production environments for many years and in one producer had evolved into two strains over a period of around 8 years. This article demonstrates the value of reviewing L. monocytogenes typing data from clinical cases together with that from foods as a means of identifying potential vehicles and sources of infection in outbreaks of listeriosis. It illustrates the importance of reviewing retrospective L. monocytogenes typing alongside enhanced surveillance data to characterize extended outbreaks and inform control measures. Also, this article highlights the advantages of WGS analysis for strain discrimination and clarification of evolutionary relationships that refine outbreak investigations and improve our understanding of L. monocytogenes in the food chain.


2021 ◽  
Author(s):  
Laura Pérez-Lago ◽  
Helena Martinez Lozano ◽  
Jose Antonio pajares Diaz ◽  
Arantxa Diaz Gomez ◽  
Marina Machado ◽  
...  

Abstract SARS-CoV-2 nosocomial outbreaks in the first COVID-19 wave were likely associated to a shortage of personal protective equipment and scare indications on control measures. Having covered these limitations, updates on current SARS-CoV-2 nosocomial outbreaks are required. We carried out an in-depth analysis of a 27-day nosocomial outbreak in a gastroenterology ward in our hospital, potentially involving 15 patients and three healthcare workers. Patients had stayed in one of three neighbouring rooms in the ward. The severity of the infections in six of the cases and a high fatality rate suggested the possible involvement of a single virulent strain persisting in those rooms. Whole genome sequencing of the strains from 12 patients and one healthcare worker revealed an unexpected complexity. Five different SARS-CoV-2 strains were identified, two infecting a single patient each, ruling out their relationship with the outbreak; the remaining three strains were involved in three independent overlapping limited transmission clusters with three, three, and five cases. Whole genome sequencing was key to understand the complexity of this outbreak.


2020 ◽  
Vol 14 (11) ◽  
pp. e0008796 ◽  
Author(s):  
Catherine N. Wilson ◽  
Caisey V. Pulford ◽  
James Akoko ◽  
Blanca Perez Sepulveda ◽  
Alexander V. Predeus ◽  
...  

Salmonella is a major cause of foodborne disease globally. Pigs can carry and shed non-typhoidal Salmonella (NTS) asymptomatically, representing a significant reservoir for these pathogens. To investigate Salmonella carriage by African domestic pigs, faecal and mesenteric lymph node samples were taken at slaughter in Nairobi, Busia (Kenya) and Chikwawa (Malawi) between October 2016 and May 2017. Selective culture, antisera testing and whole genome sequencing were performed on samples from 647 pigs; the prevalence of NTS carriage was 12.7% in Busia, 9.1% in Nairobi and 24.6% in Chikwawa. Two isolates of S. Typhimurium ST313 were isolated, but were more closely related to ST313 isolates associated with gastroenteritis in the UK than bloodstream infection in Africa. The discovery of porcine NTS carriage in Kenya and Malawi reveals potential for zoonotic transmission of diarrhoeal strains to humans in these countries, but not for transmission of clades specifically associated with invasive NTS disease in Africa.


2021 ◽  
Vol 26 (14) ◽  
Author(s):  
Klára Labská ◽  
Michaela Špačková ◽  
Ondřej Daniel ◽  
Josef Včelák ◽  
Veronika Vlasáková ◽  
...  

In August 2017, an increased incidence of Salmonella Bareilly was detected in the Czech Republic. An investigation was conducted with Slovakia to confirm the outbreak and identify the source. Probable outbreak cases were defined as cases with laboratory-confirmed S. Bareilly reported in either of the national surveillance systems, and/or the Czech and Slovak National Reference Laboratory databases from July 2017. Confirmed cases had the pulsed-field gel electrophoresis (PFGE) outbreak pulsotype or up to 5 alleles difference from outbreak cluster members by core genome multilocus sequence typing (cgMLST). PFGE and whole genome sequencing were used for isolate comparison. The same trawling questionnaire was used in both countries. By the end of October 2018, 325 cases were identified. Among 88 human S. Bareilly isolates analysed by PFGE, 82 (93%) shared an identical pulsotype; cgMLST of 17 S. Bareilly human isolates showed 1–2 allele difference. The trawling questionnaire excluded consumption of unusual or imported foods. In September 2018, an isolate closely related to the outbreak isolates was identified in a powdered egg product. A spray dryer was recognised as the contamination source and the production plant was closed. Using molecular typing methods, we detected a diffuse cross-border outbreak caused by S. Bareilly.


2021 ◽  
Author(s):  
José Afonso Guerra-Assunção ◽  
Paul A. Randell ◽  
Florencia A. T. Boshier ◽  
Michael A. Crone ◽  
Juanita Pang ◽  
...  

AbstractThe appearance of the SARS-CoV-2 lineage B.1.1.7 in the UK in late 2020, associated with faster transmission, sparked the need to find effective ways to monitor its spread. The set of mutations that characterise this lineage include a deletion in position 69 and 70 of the spike protein, which is known to be associated with Spike Gene Target Failure (SGTF) in a commonly used three gene diagnostic qPCR assay. The lower cost and faster turnaround times compared to whole genome sequencing make the use of qPCR for monitoring of the variant spread an attractive proposition. However, there are several potential issues with this approach. Here we use 826 SARS-CoV-2 samples collected in a hospital setting as part of the Hospital Onset COVID Infection (HOCI) study where qPCR was used for viral detection, followed by whole genome sequencing (WGS), to identify the factors to consider when using SGTF to infer lineage B.1.1.7 prevalence in a hospital setting, with potential implications for locations where this variant has recently been introduced.


2017 ◽  
Author(s):  
Kimon Lemonidis ◽  
Talal S. Salih ◽  
Stephanie J. Dancer ◽  
Iain S. Hunter ◽  
Nicholas P. Tucker

AbstractMulti-locus sequencing typing (MLST) is widely used to monitor the phylogeny of microbial outbreaks. However, several strains of vancomycin-resistant Enterococcus faecium (VREfm) with a missing MLST locus (pstS) have recently emerged in Australia, with a few cases also reported in England. Here, we identified similarly distinct strains circulating in two closely located hospitals in Scotland. Whole genome sequencing of five VREfm strains isolated from these hospitals identified four pstS-null strains across both hospitals, while the fifth was of a multi-locus sequence type (ST) 262, which is the first documented in the UK. All five Scottish isolates had an insertion in the tetM gene, which is associated with increased susceptibility to tetracyclines, providing no other tetracycline-resistant gene is present. Such an insertion, which encompasses a dfrG gene and two currently uncharacterised genes, was additionally identified in all tested VanA-type pstS-null VREfm strains (5 English and 18 Australian). Phylogenetic comparison with other VREfm genomes indicates that the four pstS-null Scottish isolates sequenced in this study are more closely related to pstS-null strains from Australia rather than the English pstS-null isolates. Given how rapidly such pstS-null strains have expanded in Australia, the emergence of this clone in Scotland raises concerns for a potential outbreak.


Sign in / Sign up

Export Citation Format

Share Document