Stokes M.O.,Animal Health and Veterinary Laboratories Agency |
Stokes M.O.,Kingston University |
Cottell J.L.,University of Birmingham |
Piddock L.J.V.,University of Birmingham |
And 7 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2012
Objectives: To detect and characterize Escherichia coli strains and pCT-like plasmids implicated in the dissemination of the CTX-M-14 gene in animals and humans, in England and Wales. Methods: UK CTX-M-14-producing E. coli (n=70) from cattle (n=33), turkeys (n=9), sheep (n=2) and humans (n=26) were screened using multiplex PCR for the detection of a previously characterized plasmid, pCT. Isolates found to be carrying two or more pCT genetic markers were further analysed using PFGE. Their antimicrobialresistance genes and virulence genes were also determined. These plasmids were transferred to Salmonella enterica serotype Typhimurium 26R and further examined for incompatibility type, genetic environment of the bla CTX-M-14 gene, size, restriction fragment length polymorphism (RFLP) and nikB sequence. Results: The 25 E. coli isolates carrying pCT genetic markers generated 19 different PFGE profiles, and 23 isolates had different virulence and antimicrobial-resistance gene patterns. One isolate from cattle was a verotoxigenic E. coli ('VTEC'); the rest were commensal or extra-intestinal pathogenic E. coli. pCT-like plasmids with similar molecular characteristics (size, replicon type, RFLP pattern, pCT markers and genetic environment of the bla CTX-M-14 gene) were detected in 21/25 of the field isolates, which comprised those from cattle (n=9), turkeys (n=8) and humans (n=4). All pCT-like plasmids were conjugative, and most were IncK (n=21) and had the same local genetic environment flanking the blaCTX-M-14 gene (n=23). RFLP analysis demonstrated ≥75% similarity among most plasmids (n=22). Conclusions: pCT-like plasmids were common vectors for horizontal dissemination of 30% of the bla CTX-M-14 genes to different E. coli isolates from humans, cattle and turkeys. © Crown copyright 2012.
Hopkins K.L.,Public Health England |
Kirchner M.,Veterinary Laboratories Agency |
Guerra B.,German Federal Institute for Risk Assessment |
Granier S.A.,Agence Francaise de Securite Sanitaire des Aliments |
And 6 more authors.
Eurosurveillance | Year: 2010
A marked increase in the prevalence of S. enterica serovar 4,,12:i:- with resistance to ampicillin, strep-tomycin, sulphonamides and tetracyclines (R-type ASSuT) has been noted in food-borne infections and in pigs/pig meat in several European countries in the last ten years. One hundred and sixteen strains of S. enterica serovar 4,,12:i:- from humans, pigs and pig meat isolated in England and Wales, France, Germany, Italy, Poland, Spain and the Netherlands were further subtyped by phage typing, pulsed-field gel electrophoresis and multilocus variable number tandem repeat analysis to investigate the genetic relationship among strains. PCR was performed to identify the fljB flagellar gene and the genes encoding resistance to ampicillin, streptomycin, sulphonamides and tetracyclines. Class 1 and 2 integrase genes were also sought. Results indicate that genetically related serovar 4,,12:i:- strains of definitive phage types DT193 and DT120 with ampicillin, streptomycin, sul-phonamide and tetracycline resistance encoded by blaTEM, strA-strB, sul2 and tet(B) have emerged in several European countries, with pigs the likely reservoir of infection. Control measures are urgently needed to reduce spread of infection to humans via the food chain and thereby prevent the possible pandemic spread of serovar 4,,12:i:- of R-type ASSuT as occurred with S. Typhimurium DT104 during the 1990s.
Hagenaars T.J.,Central Veterinary Institute of Wageningen |
Dekker A.,Central Veterinary Institute of Wageningen |
De Jong M.C.M.,Wageningen University |
Eble P.L.,Central Veterinary Institute of Wageningen
OIE Revue Scientifique et Technique | Year: 2011
Mathematical models for the spread of foot and mouth disease (FMD) have been developed and used for a number of purposes in the recent literature. One important purpose is predicting the effect of strategies to combat between-farm epidemic spread, in support of decision-making on epidemic control. The authors briefly review the various modelling approaches, discussing the parameters used and how estimates may be obtained for these parameters. They emphasise that, in addition to the estimation of FMD transmission parameters, the choice of model structure (including the number and type of parameters used) is also crucial. Two gaps in the knowledge of FMD transmission, related to model construction and parameter quantification, are identified: transmission between different species and the way in which vaccination affects such transmission, and route-specific FMD transmission properties. In particular, the authors pay attention to the role that small-scale transmission experiments can play in bridging these gaps.
Stokes M.O.,Animal Health and Veterinary Laboratories Agency AHVLA |
Stokes M.O.,Kingston University |
AbuOun M.,Animal Health and Veterinary Laboratories Agency AHVLA |
Umur S.,Royal Holloway, University of London |
And 6 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2013
The same plasmid carrying blaCTX-M-14b was identified from an Escherichia coli isolate and an Enterobacter cloacae isolate collected from cattle in the United Kingdom by complete plasmid sequencing. This 35,341-bp plasmid, pSAM7, had an IncX4 backbone that is 99% identical to that of pJIE143 from a human isolate in Australia. PCR screening identified pSAM7-like plasmids in three other E. coli isolates of different multilocus sequence types isolated from cattle on different farms in the United Kingdom. Copyright © 2013, American Society for Microbiology. All Rights Reserved.
Woudstra C.,ANSES French Agency for Food |
Skarin H.,National Veterinary Institute |
Anniballi F.,Istituto Superiore Of Sanita Laboratorio Alimenti |
Fenicia L.,Istituto Superiore Of Sanita Laboratorio Alimenti |
And 7 more authors.
Applied and Environmental Microbiology | Year: 2012
Clostridium botulinum types C and D, as well as their mosaic variants C-D and D-C, are associated with avian and mammalian botulism. This study reports on the development of low-density macroarrays based on the GeneDisc cycler platform (Pall-Gene-Disc Technologies) applied to the simultaneous detection of the C. botulinum subtypes C, C-D, D, and D-C. The limit of detection of the PCR assays was 38 fg of total DNA, corresponding to 15 genome copies. Artificially contaminated samples of cecum showed a limit of detection below 50 spores/g. The tests were performed with a large variety of bacterial strains, including C. botulinum types C (n=12), C-D (n=29), D (n=5), and D-C (n=10), other botulinum neurotoxin (BoNT)-producing Clostridium strains (n=20), non-BoNT-producing clostridia (n=20), and other bacterial species (n=23), and showed a high specificity. These PCR assays were compared to previously published real-time PCRs for the detection of C. botulinum in 292 samples collected from cases of botulism events in four European regions. The majority of the samples originated from wild birds (n= 108), poultry (n=60), and bovines (n=56). Among the 292 samples, 144 were positive for either the bont/C-D or the bont/D-C gene by using the GeneDisc arrays. The reliability of the results tallied to 97.94%. Interestingly, only BoNT mosaics, types C-D and D-C, were found in naturally contaminated samples whatever their animal origin and their geographical location. Further investigations should now be performed in order to check that mosaic types dominate in Europe and that acquisition of mosaic types helps in survival or adaptation to particular niche. © 2012, American Society for Microbiology.