title: Revisiting the STEC Testing Approach: Using espK and espV to Make Enterohemorrhagic Escherichia coli (EHEC) Detection More Reliable in Beef.
abstract: Current methods for screening Enterohemorrhagic Escherichia coli (EHEC) O157 and non-O157 in beef enrichments typically rely on the molecular detection of stx, eae, and serogroup-specific wzx or wzy gene fragments. As these genetic markers can also be found in some non-EHEC strains, a number of "false positive" results are obtained. Here, we explore the suitability of five novel molecular markers, espK, espV, ureD, Z2098, and CRISPRO26:H11 as candidates for a more accurate screening of EHEC strains of greater clinical significance in industrialized countries. Of the 1739 beef enrichments tested, 180 were positive for both stx and eae genes. Ninety (50%) of these tested negative for espK, espV, ureD, and Z2098, but 12 out of these negative samples were positive for the CRISPRO26:H11 gene marker specific for a newly emerging virulent EHEC O26:H11 French clone. We show that screening for stx, eae, espK, and espV, in association with the CRISPRO26:H11 marker is a better approach to narrow down the EHEC screening step in beef enrichments. The number of potentially positive samples was reduced by 48.88% by means of this alternative strategy compared to the European and American reference methods, thus substantially improving the discriminatory power of EHEC screening systems. This approach is in line with the EFSA (European Food Safety Authority) opinion on pathogenic STEC published in 2013.
authors.affiliation: Food Safety Laboratory, Université Paris-Est, Anses (French Agency for Food, Environmental and Occupational Health and Safety), Platform IdentyPath Maisons-Alfort, France.
authors.forename: Sabine
authors.initials: S
authors.lastname: Delannoy
authors.affiliation: Department of Animal and Food Sciences, Texas Tech University Lubbock, TX, USA.
authors.forename: Byron D
authors.initials: BD
authors.lastname: Chaves
authors.affiliation: Department of Animal and Food Sciences, Texas Tech University Lubbock, TX, USA.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Ison
authors.affiliation: Department of Animal and Food Sciences, Texas Tech University Lubbock, TX, USA.
authors.forename: Hattie E
authors.initials: HE
authors.lastname: Webb
authors.affiliation: Division of Microbial Toxins, National Reference Laboratory for Escherichia coli, Federal Institute for Risk Assessment Berlin, Germany.
authors.forename: Lothar
authors.initials: L
authors.lastname: Beutin
authors.affiliation: Laboratoire de Touraine, (LDA37) Conseil Départemental Tours, France.
authors.forename: José
authors.initials: J
authors.lastname: Delaval
authors.affiliation: SAS Charal Groupe Bigard Cholet, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Billet
authors.affiliation: Food Safety Laboratory, Université Paris-Est, Anses (French Agency for Food, Environmental and Occupational Health and Safety), Platform IdentyPath Maisons-Alfort, France.
authors.forename: Patrick
authors.initials: P
authors.lastname: Fach
keywords: CRISPR; O157; STEC; Z2098; espK; espV; non-O157; ureD
references.citation: J Clin Microbiol. 2015 Feb;53(2):486-92
references.pmid: 25428148
references.citation: J Clin Microbiol. 2003 Nov;41(11):4930-40
references.pmid: 14605120
references.citation: Genome Announc. 2015 Jul 30;3(4):
references.pmid: 26227606
references.citation: J Clin Microbiol. 2003 Jul;41(7):2884-93
references.pmid: 12843017
references.citation: J Clin Microbiol. 2012 Dec;50(12):4035-40
references.pmid: 23035199
references.citation: Front Cell Infect Microbiol. 2014 Jul 29;4:103
references.pmid: 25120960
references.citation: J Appl Microbiol. 2010 Nov;109(5):1696-705
references.pmid: 20618885
references.citation: J Food Prot. 2015 Apr;78(4):675-84
references.pmid: 25836391
references.citation: Front Microbiol. 2011 Apr 25;2:90
references.pmid: 21833329
references.citation: Infect Immun. 2000 Jan;68(1):64-71
references.pmid: 10603369
references.citation: J Clin Microbiol. 2013 Apr;51(4):1083-8
references.pmid: 23325824
references.citation: Microbiol Spectr. 2014 Jun;2(3):
references.pmid: 26103970
references.citation: Foodborne Pathog Dis. 2013 May;10(5):453-60
references.pmid: 23560425
references.citation: Appl Environ Microbiol. 2010 Jan;76(1):203-11
references.pmid: 19880649
references.citation: Foodborne Pathog Dis. 2009 Jun;6(5):605-11
references.pmid: 19435408
references.citation: PLoS One. 2014 Apr 21;9(4):e95379
references.pmid: 24752200
references.citation: Clin Infect Dis. 2013 May;56(10):1373-81
references.pmid: 23378282
references.citation: J Clin Microbiol. 2013 Oct;51(10):3257-62
references.pmid: 23884997
references.citation: J Infect Dis. 2005 Oct 15;192(8):1422-9
references.pmid: 16170761
references.citation: Foodborne Pathog Dis. 2013 Aug;10(8):665-77
references.pmid: 23755895
references.citation: Clin Infect Dis. 2006 Dec 15;43(12):1587-95
references.pmid: 17109294
references.citation: Mol Cell Probes. 2004 Jun;18(3):185-92
references.pmid: 15135453
references.citation: Vet Microbiol. 2012 Aug 17;158(3-4):443-5
references.pmid: 22424867
references.citation: Front Cell Infect Microbiol. 2014 Jun 18;4:81
references.pmid: 24995164
references.citation: Appl Environ Microbiol. 2011 Mar;77(6):2035-41
references.pmid: 21239543
references.citation: EFSA J. 2018 Dec 12;16(12):e05500
references.pmid: 32625785
references.citation: Int J Med Microbiol. 2013 Dec;303(8):410-21
references.pmid: 23777812
references.citation: J Appl Microbiol. 2005;98(5):1162-8
references.pmid: 15836486
references.citation: N Engl J Med. 2011 Nov 10;365(19):1771-80
references.pmid: 21696328
references.citation: Appl Environ Microbiol. 2014 Feb;80(3):1177-84
references.pmid: 24296503
references.citation: Front Cell Infect Microbiol. 2012 Dec 20;2:152
references.pmid: 23267438
references.citation: J Clin Microbiol. 2012 Nov;50(11):3485-92
references.pmid: 22895033
references.citation: J Appl Microbiol. 2009 Apr;106(4):1122-32
references.pmid: 19191965