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Silver nanoparticle effect on Salmonella enterica isolated from Northern West Egypt food, poultry, and calves. Appl Microbiol Biotechnol 2022; 106:5701-5713. [PMID: 35945362 PMCID: PMC9418292 DOI: 10.1007/s00253-022-12102-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 06/11/2022] [Accepted: 07/23/2022] [Indexed: 11/03/2022]
Abstract
A total no. of 65 Salmonella enterica isolates recovered from food samples, feces of diarrheic calves, poultry, and hospital patient in large five cities at Northern West Egypt were obtained from the Department of Microbiology, Faculty of Veterinary Medicine, Alexandria University, Alexandria, Egypt. The 65 Salmonella enterica isolates had the invA gene were grouped into 11 Salmonella enterica serovars with dominance of S. Enteritidis and S. Kentucky serovars. Their resistance pattern were characterized by using 18 antibiotics from different classes. Approximately 80% of the isolates were multidrug resistant (MDR). Enterobacterial repetitive intergenic consequences polymerase chain reaction (ERIC-PCR) typing of 7 strains of S. Enteritidis showed 5 clusters with dissimilarity 25%. S. Enteritidis clusters in 2 main groups A and B. Group A have 2 human strain (HE2 and HE3) and one food origin (FE7) with a similarity 99%. Group B divided into B1 (FE2) and B2 (FE3) with a similarity ratio ≥ 93%, while ERIC-PCR analysis of 5 strains of S. Kentucky revealed 4 ERIC types, clustered in 2 main groups A and B with similarity 75%. We studied the effect of silver nanoparticles (Ag-NPs) on 10 antibiotic resistant strains of S. Enteritidis and S. Kentucky. The broth microdilution minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were detected. Evaluation of the affection using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed different ratios of Ag-NPs and microorganism as well as at different contact time ended finally with morphological alteration of the bacteria. We submitted new method in vivo to explore the activity of nanosilver in chicken. KEY POINTS: • Importance of ERIC-PCR to determine the relatedness between Salmonella isolates. • Effect of silver nanoparticles to confront the antibacterial resistance. • Studying the effect of silver nanoparticles in vivo on infected chicken with Salmonella.
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Li Y, Yang Q, Cao C, Cui S, Wu Y, Yang H, Xiao Y, Yang B. Prevalence and characteristics of Salmonella isolates recovered from retail raw chickens in Shaanxi Province, China. Poult Sci 2020; 99:6031-6044. [PMID: 33142522 PMCID: PMC7647799 DOI: 10.1016/j.psj.2020.07.038] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/10/2020] [Accepted: 07/15/2020] [Indexed: 11/24/2022] Open
Abstract
In this study, we evaluated the prevalence of Salmonella in retail raw chickens in Shaanxi Province, China, on a monthly basis. In addition, we studied the antibiotic susceptibility, serotype, and genotype of Salmonella isolates and explored their relationships with sampling time, location, market type, and chicken type. The results showed that Salmonella was more prevalent in chickens sampled during the spring and summer than during the autumn and winter. Thirty-nine serotypes were identified from 406 Salmonella isolates, of which Salmonella typhimurium (16.7%) was the most prevalent. Other prevalent serotypes included S. thompson (12.8%), S. essen (9.1%), S. infantis (6.9%), S. rissen (5.7%), and S. enteritidis (5.4%). Approximately 71.4% of the 406 isolates were resistant to 3 or more antibiotics, 11.8% to 12 or more, and 1.7% to all 14 antibiotics tested. The most frequently detected resistance was to trimethoprim/sulfamethoxazole (82.0%), followed by nalidixic acid (71.9%) and tetracycline (59.4%). The frequencies of resistance to ampicillin, chloramphenicol, and amoxicillin/clavulanic acid were moderately high (∼50% each). Resistance to kanamycin, ceftiofur, streptomycin, gentamicin, and ciprofloxacin was less common (<40% each). Serotype distribution and antibiotic susceptibility of Salmonella isolates were related to sampling time, location, chicken type, and market type. Isolates recovered from the same sampling time, market type, location, and chicken type commonly exhibited identical or similar genotypes and antibiotic resistance profiles. However, DNA profiles and antibiotic resistance phenotypes of isolates within some serotypes were diverse. Our results revealed that multiple Salmonella subtypes with antibiotic resistance were prevalent in retail raw chickens in Shaanxi Province. Our study findings provide information for developing preventive measures against contamination of retail foods with Salmonella.
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Affiliation(s)
- Yilan Li
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China
| | - Qiuping Yang
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China
| | - Chenyang Cao
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China
| | - Shenghui Cui
- National Institutes for Food and Drug Control, Beijing 100050, China
| | - Yun Wu
- Xinjiang Agricultural University, Urumqi 830052, China
| | - Hua Yang
- Institute of Quality and Standard for Agro-products, and State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Yingping Xiao
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China.
| | - Baowei Yang
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China.
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Ni P, Xu Q, Yin Y, Liu D, Zhang J, Wu Q, Tian P, Shi X, Wang D. Prevalence and characterization of Salmonella serovars isolated from farm products in Shanghai. Food Control 2018. [DOI: 10.1016/j.foodcont.2017.10.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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ASSIS FEA, DALLAGASSA CB, FARAH SMSS, SOUZA EM, PEDROSA FO, CHUBATSU LS, FADEL-PICHETH CMT. Molecular characterisation of Salmonella strains isolated from outbreaks and sporadic cases of diarrhoea occurred in Paraná State, South of Brazil. Epidemiol Infect 2017; 145:1953-1960. [PMID: 28367777 PMCID: PMC9203290 DOI: 10.1017/s0950268817000619] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 12/29/2016] [Accepted: 03/07/2017] [Indexed: 11/07/2022] Open
Abstract
A total of 46 strains of Salmonella isolated from patients with sporadic diarrhoea or involved in foodborne outbreaks were analysed by PCR for genus identification and serotyping. Subtyping was performed using pulsed-field gel electrophoresis (PFGE) and multiple amplification of phage locus typing (MAPLT) for seven variable loci. Bacteria were identified as belonging to serotype Enteritidis (33 strains; 71·7%) or Typhimurium (13 strains; 28·3%). A high similarity coefficient (94·6%) was observed in the Salmonella Enteritidis group for which were found three related PFGE profiles and only one MAPLT; strains representing profile PA/P1/MI were prevalent (27; 81·8%). Two Salmonella Typhimurium isolates were untypeable by PFGE. The remaining 11 strains had eight PFGE and three MAPLT profiles. The discriminatory power of MAPLT was lower than that of PFGE. Salmonella Enteritidis of clonal nature is predominant in Paraná State, with the most prevalent profile PA/P1/M1 associated with sporadic diarrhoea and with seven of nine reported outbreaks. In conclusion, PFGE shows higher discriminatory power among Salmonella strains.
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Affiliation(s)
- F. E. A. ASSIS
- Departamento de Análises Clínicas, Universidade Federal do Paraná, Curitiba-PR, Brazil
| | - C. B. DALLAGASSA
- Departamento de Análises Clínicas, Universidade Federal do Paraná, Curitiba-PR, Brazil
| | | | - E. M. SOUZA
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba-PR, Brazil
| | - F. O. PEDROSA
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba-PR, Brazil
| | - L. S. CHUBATSU
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba-PR, Brazil
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Fardsanei F, Nikkhahi F, Bakhshi B, Salehi TZ, Tamai IA, Soltan Dallal MM. Molecular characterization of Salmonella enterica serotype Enteritidis isolates from food and human samples by serotyping, antimicrobial resistance, plasmid profiling, (GTG)5-PCR and ERIC-PCR. New Microbes New Infect 2016; 14:24-30. [PMID: 27656286 PMCID: PMC5021763 DOI: 10.1016/j.nmni.2016.07.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/27/2016] [Accepted: 07/29/2016] [Indexed: 11/16/2022] Open
Abstract
In recent years, Salmonella enterica serovar Enteritidis has been a primary cause of human salmonellosis in many countries. The major objective of this study was to investigate genetic diversity among Salmonella Enteritidis strains from different origins (food and human) by Enterobacterial Repetitive Intergenic Consensus (ERIC) -PCR, as well as to assess their plasmid profiling and antimicrobial resistance. A total of 30 Salmonella Enteritidis isolates, 15 from food samples (chicken, lamb, beef and duck meats) and 15 from clinical samples were collected in Tehran. Identification of isolates as Salmonella was confirmed by using conventional standard biochemical and serological tests. Multiplex-PCR was used for serotyping of isolates to identify Salmonella Enteritidis. Antimicrobial susceptibility testing to 16 agents founds drug resistance patterns among Salmonella Enteritidis isolates. No resistance was observed to cephalexin, ceftriaxone, ceftazidime and cefotaxime, ciprofloxacin, imipenem or meropenem, chloramphenicol and gentamicin. The highest resistance (96.7%) was observed to nitrofurantoin. Seven plasmid profiles (P1-P7) were detected, and a 68-kb plasmid was found in all isolates. Two different primers; ERIC and (GTG)5 were used for genotyping, which each produced four profiles. The majority of clinical and food isolates fell into two separate common types (CTs) with a similar percentage of 95% by ERIC-PCR. Using primer (GTG)5, 29 isolates incorporated in three CTs with 70% of isolates showing a single banding pattern. Limited genetic diversity among human and food isolates of Salmonella Enteritidis may indicate that contaminated foods were possibly the source of human salmonellosis. These results confirmed that ERIC-PCR genotyping has limited discriminatory power for Salmonella Enteritidis of different origin.
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Affiliation(s)
- F Fardsanei
- Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Science, Tehran, Iran
| | - F Nikkhahi
- Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Science, Tehran, Iran
| | - B Bakhshi
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; Food Microbiology Research Centre, Tehran University of Medical Sciences, Tehran, Iran
| | - T Z Salehi
- Department of Microbiology, Faculty of Veterinary Medicine, University of Tehran, Iran
| | - I A Tamai
- Department of Microbiology, Faculty of Veterinary Medicine, University of Tehran, Iran; Department of Microbiology, Buali Sina University, Hamedan, Iran
| | - M M Soltan Dallal
- Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Science, Tehran, Iran; Food Microbiology Research Centre, Tehran University of Medical Sciences, Tehran, Iran
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Diffusion and persistence of multidrug resistant Salmonella Typhimurium strains phage type DT120 in southern Italy. BIOMED RESEARCH INTERNATIONAL 2015; 2015:265042. [PMID: 26060815 PMCID: PMC4427771 DOI: 10.1155/2015/265042] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 08/29/2014] [Accepted: 09/11/2014] [Indexed: 12/02/2022]
Abstract
Sixty-two multidrug resistant Salmonella enterica serovar Typhimurium strains isolated from 255 clinical strains collected in Southern Italy in 2006–2008 were characterised for antimicrobial resistance genes, pulsotype, and phage type. Most strains (83.9%) were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (ACSSuT) encoded in 88.5% by the Salmonella genomic island (SGI1) and in 11.5% by the InH-like integron (blaOXA-30–aadA1) and catA1, sul1, and tet(B) genes. STYMXB.0061 (75%) and DT120 (84.6%) were the prevalent pulsotype and phage type identified in these strains, respectively. Five other resistance patterns were found either in single or in a low number of isolates. The pandemic clone DT104 (ACSSuT encoded by SGI1) has been identified in Italy since 1992, while strains DT120 (ACSSuT encoded by SGI1) have never been previously reported in Italy. In Europe, clinical strains DT120 have been reported from sporadic outbreaks linked to the consumption of pork products. However, none of these strains were STYMXB.0061 and SGI1 positive. The prevalent identification and persistence of DT120 isolates would suggest, in Southern Italy, a phage type shifting of the pandemic DT104 clone pulsotype STYMXB.0061. Additionally, these findings raise epidemiological concern about the potential diffusion of these emerging multidrug resistant (SGI linked) DT120 strains.
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Subtyping of Salmonella isolates on retail raw chicken in China by pulsed-field gel electrophoresis and plasmid analysis. Food Control 2015. [DOI: 10.1016/j.foodcont.2014.07.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Wang Y, Yang B, Wu Y, Zhang Z, Meng X, Xi M, Wang X, Xia X, Shi X, Wang D, Meng J. Molecular characterization of Salmonella enterica serovar Enteritidis on retail raw poultry in six provinces and two National cities in China. Food Microbiol 2014; 46:74-80. [PMID: 25475269 DOI: 10.1016/j.fm.2014.07.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 06/18/2014] [Accepted: 07/18/2014] [Indexed: 01/09/2023]
Abstract
One hundred and twenty six Salmonella Enteritidis isolates recovered from 1152 retail raw poultries were characterized by antimicrobial susceptibility test, pulsed-field gel electrophoresis (PFGE), presence of quinolone resistance (Qnr) associated genes, Class I integron, extended spectrum beta-lactamases (ESBLs) encoding genes, and mutations in quinolone resistance-determining region (QRDR) of GyrA and ParC. Resistance was most frequently found to nalidixic acid (88.1%), followed by to tetracycline (65.9%), sulfisoxazole (65.1%), and ampicillin (61.9%), and a less extent to cefoxitin (8.7%), gatifloxacin (8.7%), levofloxacin (7.9%), ceftriaxone (7.1%), and ceftiofur (6.3%). One hundred and twenty three (98.4%) isolates were resistant to at least one antibiotic, and 93 (74.4%) to at least four antibiotics. aac(6')-Ib-cr, qnrB, qnrA and qnrS genes were detected in 15 (11.9%), 11 (8.7%), 6 (4.8%) and 1 (0.8%) isolates, respectively. Amino acid substitutions of Ser83Tyr, Asp87Asn, Asp87Tyr, Asp87Gly and Ser83Phe/Asp87Asn were detected in QRDR of GyrA, Arg80Ser was the unique mutation in ParC. Eight isolates were detected with amino acid substitution both in GyrA and ParC. Three isolates carried Class I integron that harboring dfrA17-aadA5, dhfR1-aadA1, and dfrA1, respectively. Five isolates were detected carrying bla(TEM)-bla(ACC) (n = 1), bla(TEM) (n = 1), bla(TEM)-bla(OxA) (n = 3), respectively. Genetic diversities (D = 0.9255) were found among isolates based on PFGE analysis.
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Affiliation(s)
- Yin Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China
| | - Baowei Yang
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China.
| | - Yun Wu
- Xinjiang Agricultural University, Urumqi, 830052, China
| | - Zengfeng Zhang
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China
| | - Xiaofeng Meng
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China
| | - Meili Xi
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China
| | - Xin Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China
| | - Xiaodong Xia
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China
| | - Xianming Shi
- Shanghai Jiaotong University, Shanghai, 200240, China
| | - Dapeng Wang
- Shanghai Jiaotong University, Shanghai, 200240, China
| | - Jianghong Meng
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China
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Ozdemir K, Acar S. Plasmid profile and pulsed-field gel electrophoresis analysis of Salmonella enterica isolates from humans in Turkey. PLoS One 2014; 9:e95976. [PMID: 24852084 PMCID: PMC4031231 DOI: 10.1371/journal.pone.0095976] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 03/31/2014] [Indexed: 11/30/2022] Open
Abstract
This study was conducted for typing Salmonella enterica subspecies enterica strains in Turkey using pulsed–field gel electrophoresis (PFGE) and plasmid DNA profile analysis. Fourty-two strains were isolated from clinical samples obtained from unrelated patients with acute diarrhea. The samples were collected from state hospitals and public health laboratories located at seven provinces in different regions of Turkey at different times between 2004 and 2010. The strains were determined to belong to 4 different serovars. The Salmonella enterica strains belonged to the serovars Salmonella Enteritidis (n = 23), Salmonella Infantis (n = 14), Salmonella Munchen (n = 2), and Salmonella Typhi (n = 3). Forty-two Salmonella enterica strains were typed with PFGE methods using XbaI restriction enzyme and plasmid analysis. At the end of typing, 11 different PFGE band profiles were obtained. Four different PFGE profiles (type 1, 4, 9, and 10) were found among serotype S. Enteritidis species, 3 different PFGE profiles (type 3, 5, 6) were found among S. Infantis species, 2 different PFGE profiles were found among S. Typhi species (type 2 and 11), and 2 different PFGE profiles were found among S. Munchen species (type 7, 8). The UPGMA dendrogram was built on the PFGE profiles. In this study, it was determined that 4 strains of 42 Salmonella enterica strains possess no plasmid, while the isolates have 1–3 plasmids ranging from 5.0 to 150 kb and making 12 different plasmid profiles (P1–P12). In this study, we have applied the analysis of the PFGE patterns and used bioinformatics methods to identify both inter and intra serotype relationships of 4 frequently encountered serotypes for the first time in Turkey.
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Affiliation(s)
- Kerem Ozdemir
- Yuzuncu Yıl University, Faculty of Science, Department of Biology, Van, Turkey
- * E-mail:
| | - Sumeyra Acar
- Public Health Institution of Turkey, Ankara, Turkey
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Kweon OG, Kim JS, Kim GO, Lee CI, Jeong KH, Kim J. Characterization ofSalmonellaspp. Clinical Isolates in Gyeongsangbuk-do Province, 2012 to 2013. ANNALS OF CLINICAL MICROBIOLOGY 2014. [DOI: 10.5145/acm.2014.17.2.50] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Oh-Geun Kweon
- Division of Microbiology, Gyeongsangbuk-do Provincial Government Institute of Health and Environment, Cheongwon, Korea
| | - Jin Seok Kim
- Division of Enteric Diseases, Center for Infectious Diseases, Korea National Institute of Health, Cheongwon, Korea
| | - Gou-Ok Kim
- Division of Microbiology, Gyeongsangbuk-do Provincial Government Institute of Health and Environment, Cheongwon, Korea
| | - Chang-Il Lee
- Division of Microbiology, Gyeongsangbuk-do Provincial Government Institute of Health and Environment, Cheongwon, Korea
| | - Kwang-Hyeon Jeong
- Division of Microbiology, Gyeongsangbuk-do Provincial Government Institute of Health and Environment, Cheongwon, Korea
| | - Junyoung Kim
- Division of Enteric Diseases, Center for Infectious Diseases, Korea National Institute of Health, Cheongwon, Korea
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Resistance genes, phage types and pulsed field gel electrophoresis pulsotypes in Salmonella enterica strains from laying hen farms in southern Italy. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2013; 10:3347-62. [PMID: 23924880 PMCID: PMC3774442 DOI: 10.3390/ijerph10083347] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 07/11/2013] [Accepted: 07/29/2013] [Indexed: 11/17/2022]
Abstract
Twenty-four Salmonella enterica isolates (13 serovar Enteritidis and 11 Typhimurium) isolated from 5,600 samples from intensive laying hen farms in Italy in 1998-2007 were characterized for antimicrobial resistance genes, pulsotype and phage type. Most of S. Typhimurium strains were pulsotype STYMXB.0147 (81.8%), phage type DT143 and resistant to sulfamethoxazole encoded by sul2. Two multidrug resistant (MDR) strains were identified. One strain, STYMXB.0061, was resistant to ampicillin (A), chloramphenicol (C), streptomycin (S), sulfamethoxazole (Su) and tetracycline (T) encoded by the Salmonella Genomic Island SGI1. The second MDR strain, STYMXB.0110, was resistant to SSuT encoded by sul1 and sul2, aadA1 and tet(C)-flanked by an IS26 element, respectively. The tet(C) gene has been reported to confer low levels of resistance and it has very rarely been detected in S. Typhimurium from poultry. In the current study, the MIC value (32 µg/mL) was consistent with the breakpoint (≥16 µg/mL) reported for Enterobacteriaceae. Most of the S. Enteritidis strains were resistant to Su (encoded by sul2). One MDR strain (ANxSSuT) was identified. With the exception of nalidixic acid (Nx), the resistances were respectively encoded by bla(TEM), strAB, sul2 and tet(A) harbored by an IncN conjugative plasmid. All isolates were pulsotype SENTXB.0001 with PT14b being the most prevalent identified phage type (57.1%). In Europe, SENTXB.0001 is the predominant PFGE profile from clinical cases and the identification of PT14b has steadily been on the increase since 2001. The findings presented in this study highlight the potential spread of S. Enteritidis phage types PT14b and S. Typhimurium DT143 in a field of particular relevance for zoonoses. Additional, the presence of resistance genes and genetic elements (conjugative plasmid and IS element) underlines the need to assess routinely studies in field, such as poultry farms, relevant fot the public health and suitable for the storage and diffusion of antimicrobial resistance.
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Dewaele I, Rasschaert G, Bertrand S, Wildemauwe C, Wattiau P, Imberechts H, Herman L, Ducatelle R, De Reu K, Heyndrickx M. Molecular characterization of Salmonella Enteritidis: comparison of an optimized multi-locus variable-number of tandem repeat analysis (MLVA) and pulsed-field gel electrophoresis. Foodborne Pathog Dis 2013; 9:885-95. [PMID: 23035725 DOI: 10.1089/fpd.2012.1199] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Salmonella Enteritidis (SE) is a genetically homogenous serovar, which makes optimal subtype discrimination crucial for epidemiological research. This study describes the development and evaluation of an optimized multiple-locus variable number tandem-repeat assay (MLVA) for characterization of SE. The typeability and discriminatory power of this MLVA was determined on a selected collection of 60 SE isolates and compared with pulsed-field gel electrophoresis (PFGE) using restriction enzymes XbaI, NotI, or SfiI. In addition, the estimated Wallace coefficient (W) was calculated to assess the congruence of the typing methods. Selection of epidemiologically unrelated isolates and more related isolates (originating from layer farms) was also based on the given phage type (PT). When targeting six loci, MLVA generated 16 profiles, while PFGE produced 10, 9, and 16 pulsotypes using XbaI, NotI, and SfiI, respectively, for the entire strain collection. For the epidemiologically unrelated isolates, MLVA had the highest discriminatory power and showed good discrimination between isolates from different layer farms and among isolates from the same layer farm. MLVA performed together with PT showed higher discriminatory power compared to PFGE using one restriction enzyme together with PT. Results showed that combining PT with the optimized MLVA presented here provides a rapid typing tool with good discriminatory power for characterizing SE isolates of various origins and isolates originating from the same layer farm.
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Affiliation(s)
- Isabelle Dewaele
- Technology and Food Science Unit, Institute for Agricultural and Fisheries Research, Melle, Belgium
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13
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Shariat N, DiMarzio MJ, Yin S, Dettinger L, Sandt CH, Lute JR, Barrangou R, Dudley EG. The combination of CRISPR-MVLST and PFGE provides increased discriminatory power for differentiating human clinical isolates of Salmonella enterica subsp. enterica serovar Enteritidis. Food Microbiol 2012; 34:164-73. [PMID: 23498194 DOI: 10.1016/j.fm.2012.11.012] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 11/16/2012] [Accepted: 11/20/2012] [Indexed: 10/27/2022]
Abstract
Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) is a major cause of foodborne salmonellosis. Rapid, efficient and accurate methods for identification are required to track specific strains of S. Enteritidis during outbreaks of human salmonellosis. By exploiting the hypervariable nature of virulence genes and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs), we previously developed a powerful sequence-based subtyping approach, designated CRISPR-MVLST. To substantiate the applicability of CRISPR-MVLST, we analyzed a broad set of S. Enteritidis isolates collected over a six-year period. Among 141 isolates we defined 22 Enteritidis Sequence Types (ESTs), the majority of which were novel. Notably, strains exhibiting the common PFGE pattern, JEGX01.0004 (characteristic of ∼40% of S. Enteritidis isolates in the United States), were separated into twelve distinct sequence types. Conversely, isolates of EST4, the most predominant EST we observed, comprised eight different PFGE patterns. Importantly, we showed that some genotypes that were previously associated with the food supply chain at the farm level have now been identified in clinical samples. CRISPR sequence data shows subtle but distinct differences among different alleles of S. Enteritidis, suggesting that evolution of these loci occurs vertically, as opposed to previously reported evolution by spacer acquisition in other bacteria.
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Affiliation(s)
- Nikki Shariat
- Department of Food Science, 326 Food Science Building, The Pennsylvania State University, University Park, PA 16802, USA
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Camarda A, Pupillo A, Pugliese N, Circella E, Dionisi AM, Ricci A, Pazzani C. Phenotypic and genetic traits of Salmonella enterica subsp. serovar Typhimurium strains causing salmonellosis foci in rabbit farms from Southern Italy in 1999-2003. Res Vet Sci 2012. [PMID: 23178046 DOI: 10.1016/j.rvsc.2012.10.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this study, we characterised the Salmonella Typhimurium strains responsible for four outbreaks which occurred in distinct rabbit farms (Southern Italy) from 1999 to 2003. Strains were typed by Pulsed Field Gel Electrophoresis (PFGE) and the genetic basis of antimicrobial resistance was established. A major group of clonally related isolates, pulsotype STYMXB.0061, accounted for three of the salmonellosis foci. Strains were resistant to streptomycin, chloramphenicol, tetracycline, ampicillin and sulphonamides encoded respectively by the aadA2, floR, tetG, blaPSE-1, sul1 gene cluster harboured by a Salmonella Genomic Island 1. The clonally related group of isolates included strains phage type DT104, DT12 or undefined type (NT). The fourth salmonellosis focus was caused by a strain pulsotype STYMXB.0147, resistant to sulphonamides (encoded by sul2) and phage type U302. Results provided first molecular characterisation of S. Typhimurium strains isolated from rabbit farms in Italy and highlighted the presence of the pulsotype STYMXB.0061 even before its wide detection among human clinical isolates collected in Italy in the mid 2000s from clinical cases.
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Affiliation(s)
- Antonio Camarda
- Dipartimento di Sanità Pubblica e Zootecnica, Università di Bari, strada provinciale per Casamassima Km 3, 70010 Valenzano-Bari, Italy
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Dewaele I, Rasschaert G, Wildemauwe C, Van Meirhaeghe H, Vanrobaeys M, De Graef E, Herman L, Ducatelle R, Heyndrickx M, De Reu K. Polyphasic characterization of Salmonella Enteritidis isolates on persistently contaminated layer farms during the implementation of a national control program with obligatory vaccination: A longitudinal study. Poult Sci 2012; 91:2727-35. [DOI: 10.3382/ps.2012-02218] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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16
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Achtman M, Wain J, Weill FX, Nair S, Zhou Z, Sangal V, Krauland MG, Hale JL, Harbottle H, Uesbeck A, Dougan G, Harrison LH, Brisse S. Multilocus sequence typing as a replacement for serotyping in Salmonella enterica. PLoS Pathog 2012; 8:e1002776. [PMID: 22737074 PMCID: PMC3380943 DOI: 10.1371/journal.ppat.1002776] [Citation(s) in RCA: 455] [Impact Index Per Article: 37.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 05/10/2012] [Indexed: 12/15/2022] Open
Abstract
Salmonella enterica subspecies enterica is traditionally subdivided into serovars by serological and nutritional characteristics. We used Multilocus Sequence Typing (MLST) to assign 4,257 isolates from 554 serovars to 1092 sequence types (STs). The majority of the isolates and many STs were grouped into 138 genetically closely related clusters called eBurstGroups (eBGs). Many eBGs correspond to a serovar, for example most Typhimurium are in eBG1 and most Enteritidis are in eBG4, but many eBGs contained more than one serovar. Furthermore, most serovars were polyphyletic and are distributed across multiple unrelated eBGs. Thus, serovar designations confounded genetically unrelated isolates and failed to recognize natural evolutionary groupings. An inability of serotyping to correctly group isolates was most apparent for Paratyphi B and its variant Java. Most Paratyphi B were included within a sub-cluster of STs belonging to eBG5, which also encompasses a separate sub-cluster of Java STs. However, diphasic Java variants were also found in two other eBGs and monophasic Java variants were in four other eBGs or STs, one of which is in subspecies salamae and a second of which includes isolates assigned to Enteritidis, Dublin and monophasic Paratyphi B. Similarly, Choleraesuis was found in eBG6 and is closely related to Paratyphi C, which is in eBG20. However, Choleraesuis var. Decatur consists of isolates from seven other, unrelated eBGs or STs. The serological assignment of these Decatur isolates to Choleraesuis likely reflects lateral gene transfer of flagellar genes between unrelated bacteria plus purifying selection. By confounding multiple evolutionary groups, serotyping can be misleading about the disease potential of S. enterica. Unlike serotyping, MLST recognizes evolutionary groupings and we recommend that Salmonella classification by serotyping should be replaced by MLST or its equivalents. Microbiologists have used serological and nutritional characteristics to subdivide pathogenic bacteria for nearly 100 years. These subdivisions in Salmonella enterica are called serovars, some of which are thought to be associated with particular diseases and epidemiology. We used MultiLocus Sequence-based Typing (MLST) to identify clusters of S. enterica isolates that are related by evolutionary descent. Some clusters correspond to serovars on a one to one basis. But many clusters include multiple serovars, which is of public health significance, and most serovars span multiple, unrelated clusters. Despite its broad usage, serological typing of S. enterica has resulted in confusing systematics, with a few exceptions. We recommend that serotyping for strain discrimination of S. enterica be replaced by a DNA-based method, such as MLST. Serotyping and other non-sequence based typing methods are routinely used for detecting outbreaks and to support public health responses. Moving away from these methods will require a major shift in thinking by public health microbiology laboratories as well as national and international agencies. However, a transition to the routine use of MLST, supplemented where appropriate by even more discriminatory sequence-based typing methods based on entire genomes, will provide a clearer picture of long-term transmission routes of Salmonella, facilitate data transfer and support global control measures.
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Affiliation(s)
- Mark Achtman
- Environmental Research Institute and Department of Microbiology, University College Cork, Cork, Ireland.
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de Oliveira FA, Pasqualotto AP, da Silva WP, Tondo EC. Characterization of Salmonella Enteritidis isolated from human samples. Food Res Int 2012. [DOI: 10.1016/j.foodres.2010.09.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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18
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Cho JK, Kang MS, Kim KS. Serotypes, antimicrobial resistance of Salmonella spp. and plasmid profiles, phage types, PFGE of S. Enteritidis and S. Typhimurium isolated from ducks in Daegu-Gyeongbuk province. ACTA ACUST UNITED AC 2011. [DOI: 10.7853/kjvs.2011.34.3.217] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Revival of an old problem: an increase in Salmonella enterica serovar Typhimurium definitive phage type 8 infections in 2010 in England and Northern Ireland linked to duck eggs. Epidemiol Infect 2011; 140:146-9. [PMID: 21470442 DOI: 10.1017/s0950268811000586] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Salmonella enterica serovar Typhimurium definitive phage type (DT) 8 is uncommon in humans in the UK. In July 2010, the Health Protection Agency reported an excess isolation rate of pan-susceptible S. Typhimurium DT8 in England and Northern Ireland. By the end of October, this amounted to 81 laboratory-confirmed human cases for all regions of England and Northern Ireland in 2010, an increase of 26% and 41% on 2009 and 2008, respectively. Descriptive epidemiological investigation found a strong association with infection and consumption of duck eggs. Duck eggs contaminated with S. Typhimurium DT8 were collected from a patient's home and also at farms in the duck-egg supply chain. Although duck eggs form a small part of total UK eggs sales, there has been significant growth in sales in recent years. This is the first known outbreak of salmonellosis linked to duck eggs in the UK since 1949 and highlighted the impact of a changing food source and market on the re-emergence of salmonellosis linked to duck eggs. Control measures by the duck-egg industry should be improved along with a continued need to remind the public and commercial caterers of the potential high risks of contracting salmonellosis from duck eggs.
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Antimicrobial resistance among invasive nontyphoidal Salmonella enterica isolates in the United States: National Antimicrobial Resistance Monitoring System, 1996 to 2007. Antimicrob Agents Chemother 2011; 55:1148-54. [PMID: 21199924 DOI: 10.1128/aac.01333-10] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nontyphoidal salmonellae (NTS) are important causes of community-acquired bloodstream infection. We describe patterns of antimicrobial resistance among invasive NTS in the United States. We compared bloodstream NTS isolates with those from stool submitted to the National Antimicrobial Resistance Monitoring System (NARMS) from 1996 to 2007. We describe antimicrobial resistance among invasive strains by serogroup and serotype. Of the 19,302 NTS isolates, 17,804 (92.2%) were from stool or blood. Of these, 1,050 (5.9%) were bloodstream isolates. The median ages (ranges) of patients with and without bacteremia were 36 (<1 to 97) years and 20 (<1 to 105) years, respectively (P < 0.001). Males (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.06 to 1.38) and those ≥65 years of age were at greater risk for invasive disease. Salmonella enterica serotypes Enteritidis, Typhimurium, and Heidelberg were the most common serotypes isolated from blood; S. enterica serotypes Dublin, Sandiego, and Schwarzengrund were associated with the greatest risk for bloodstream isolation. Of invasive isolates, 208 (19.8%) were resistant to ampicillin, 117 (11.1%) to chloramphenicol, and 26 (2.5%) to trimethoprim-sulfamethoxazole; 28 (2.7%) isolates were resistant to nalidixic acid and 26 (2.5%) to ceftriaxone. Antimicrobial resistance to traditional agents is common. However, the occurrence of nalidixic acid and ceftriaxone resistance among invasive NTS is cause for clinical and public health vigilance.
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Kauko T, Haukka K, Abuoun M, Anjum MF, Woodward MJ, Siitonen A. Phenotype MicroArray in the metabolic characterisation of Salmonella serotypes Agona, Enteritidis, Give, Hvittingfoss, Infantis, Newport and Typhimurium. Eur J Clin Microbiol Infect Dis 2010; 29:311-7. [PMID: 20094898 DOI: 10.1007/s10096-009-0859-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2009] [Accepted: 12/11/2009] [Indexed: 11/24/2022]
Abstract
The Phenotype MicroArray (PM) technology was used to study the metabolic characteristics of 29 Salmonella strains belonging to seven serotypes of S. enterica spp. enterica. Strains of serotypes Typhimurium (six strains among definite phage types DTs 1, 40 and 104) and Agona (two strains) were tested for 949 substrates, Enteritidis (six strains of phage type PT1), Give, Hvittingfoss, Infantis and Newport strains (two of each) were tested for 190 substrates and seven other Agona strains for 95 substrates. The strains represented 18 genotypes in pulsed-field gel electrophoresis (PFGE). Among 949 substrates, 18 were identified that could be used to differentiate between the strains of those seven serotypes or within a single serotype. Unique metabolic differences between the Finnish endemic Typhimurium DT1 and Agona strains were detected, for example, in the metabolism of D-tagatose, D-galactonic acid gamma-lactone and L-proline as a carbon source. Thus, the PM technique is a useful tool for identifying potential differential markers on a metabolic basis that could be used for epidemiological surveillance.
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Affiliation(s)
- T Kauko
- Bacteriology Unit, Department of Infectious Diseases Surveillance and Control, National Institute for Health and Welfare (THL), P.O. Box 30, 00271 Helsinki, Finland
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22
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Lim SK, Lee HS, Nam HM, Jung SC, Koh HB, Roh IS. Antimicrobial Resistance and Phage Types of Salmonella Isolates from Healthy and Diarrheic Pigs in Korea. Foodborne Pathog Dis 2009; 6:981-7. [DOI: 10.1089/fpd.2009.0293] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Suk-Kyung Lim
- National Veterinary Research and Quarantine Service, Anyang, Republic of Korea
| | - Hee-Soo Lee
- National Veterinary Research and Quarantine Service, Anyang, Republic of Korea
| | - Hyang-Mi Nam
- National Veterinary Research and Quarantine Service, Anyang, Republic of Korea
| | - Suk-Chan Jung
- National Veterinary Research and Quarantine Service, Anyang, Republic of Korea
| | - Hong-Bum Koh
- Department of Veterinary Microbiology, Chonnam National University, Gwangju, Republic of Korea
| | - In-Soon Roh
- National Veterinary Research and Quarantine Service, Anyang, Republic of Korea
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Irvine WN, Gillespie IA, Smyth FB, Rooney PJ, McClenaghan A, Devine MJ, Tohani VK. Investigation of an outbreak of Salmonella enterica serovar Newport infection. Epidemiol Infect 2009; 137:1449-56. [PMID: 19296871 DOI: 10.1017/s0950268809002416] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A large outbreak of Salmonella enterica serotype Newport infection occurred in Northern Ireland during September and October 2004. Typing of isolates from patients confirmed that this strain was indistinguishable from that in concurrent outbreaks in regions of England, in Scotland and in the Isle of Man. A total of 130 cases were distributed unequally across local government district areas in Northern Ireland. The epidemic curve suggested a continued exposure over about 4 weeks. A matched case-control study of 23 cases and 39 controls found a statistically significant association with a history of having eaten lettuce in a meal outside the home and being a case (odds ratio 23.7, 95% confidence interval 1.4-404.3). This exposure was reported by 57% of cases. Although over 300 food samples were tested, none yielded any Salmonella spp. Complexity and limited traceability in salad vegetable distribution hindered further investigation of the ultimate source of the outbreak.
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Affiliation(s)
- W N Irvine
- Communicable Disease Surveillance Centre Northern Ireland, McBrien Building, Belfast City Hospital, Lisburn Road, Belfast, UK.
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24
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Salmonella enterica serotype 4,5,12:i:-, an emerging Salmonella serotype that represents multiple distinct clones. J Clin Microbiol 2009; 47:3546-56. [PMID: 19741087 DOI: 10.1128/jcm.00546-09] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The prevalence, among human clinical cases, of Salmonella enterica serotype 4,5,12:i:-, a serotype antigenically similar to Salmonella enterica serotype Typhimurium but lacking second-phase flagellar antigens, has increased considerably over the last 10 years. To probe the evolution and ecology of this emerging serotype, we characterized 190 Salmonella isolates initially classified as Salmonella serotypes 4,5,12:i:- (n = 90) and Typhimurium (n = 100) and obtained from various sources in the United States and Spain. These isolates were characterized into six sequence types (determined by multilocus sequence typing [MLST]) and 79 pulsed-field gel electrophoresis types. The majority of Salmonella serotype 4,5,12:i:- and Typhimurium isolates (85 and 84 isolates, respectively) represented a single MLST type. Existing genome information revealed different genome deletions (which included genes responsible for phase 2 flagellum expression) in four Spanish Salmonella serotype 4,5,12:i:- isolates and one U.S. Salmonella serotype 4,5,12:i:- isolate. Fifty-nine isolates of both serotypes, representing different sources and geographical locations as well as different molecular subtypes, were thus screened for the presence of six genes and one specific region, all of which were previously found to show variable presence among Salmonella serotype 4,5,12:i:- and Typhimurium strains. All Salmonella serotype 4,5,12:i:- isolates lacked the phase 2 flagella genes fljA and fljB, which were present in all Salmonella serotype Typhimurium isolates. While all Spanish Salmonella serotype 4,5,12:i:- isolates carried the same deletion surrounding fljAB, all but two U.S. isolates showed a different genomic deletion; the two atypical U.S. isolates represented the "Spanish" deletion genotype and a unique deletion genotype. Salmonella serotype 4,5,12:i:- thus appears to represent at least two common clones, which cannot easily be differentiated with standard diagnostic procedures.
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25
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Pan Z, Carter B, Núñez-García J, AbuOun M, Fookes M, Ivens A, Woodward MJ, Anjum MF. Identification of genetic and phenotypic differences associated with prevalent and non-prevalent Salmonella Enteritidis phage types: analysis of variation in amino acid transport. MICROBIOLOGY-SGM 2009; 155:3200-3213. [PMID: 19574306 DOI: 10.1099/mic.0.029405-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this study, differences at the genetic level of 37 Salmonella Enteritidis strains from five phage types (PTs) were compared using comparative genomic hybridization (CGH) to assess differences between PTs. There were approximately 400 genes that differentiated prevalent (4, 6, 8 and 13a) and sporadic (11) PTs, of which 35 were unique to prevalent PTs, including six plasmid-borne genes, pefA, B, C, D, srgC and rck, and four chromosomal genes encoding putative amino acid transporters. Phenotype array studies also demonstrated that strains from prevalent PTs were less susceptible to urea stress and utilized l-histidine, l-glutamine, l-proline, l-aspartic acid, gly-asn and gly-gln more efficiently than PT11 strains. Complementation of a PT11 strain with the transporter genes from PT4 resulted in a significant increase in utilization of the amino acids and reduced susceptibility to urea stress. In epithelial cell association assays, PT11 strains were less invasive than other prevalent PTs. Most strains from prevalent PTs were better biofilm formers at 37 degrees C than at 28 degrees C, whilst the converse was true for PT11 strains. Collectively, the results indicate that genetic and corresponding phenotypic differences exist between strains of the prevalent PTs 4, 6, 8 and 13a and non-prevalent PT11 strains that are likely to provide a selective advantage for strains from the former PTs and could help them to enter the food chain and cause salmonellosis.
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Affiliation(s)
- Zhensheng Pan
- School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK.,Department of Food and Environmental Safety, Veterinary Laboratories Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Ben Carter
- Department of Food and Environmental Safety, Veterinary Laboratories Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Javier Núñez-García
- Department of Food and Environmental Safety, Veterinary Laboratories Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Manal AbuOun
- Department of Food and Environmental Safety, Veterinary Laboratories Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - María Fookes
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Al Ivens
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Martin J Woodward
- Department of Food and Environmental Safety, Veterinary Laboratories Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Muna F Anjum
- Department of Food and Environmental Safety, Veterinary Laboratories Agency-Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
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26
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A prolonged outbreak of Salmonella Typhimurium infection related to an uncommon vehicle: hard cheese made from raw milk. Epidemiol Infect 2009; 137:1548-57. [PMID: 19296867 DOI: 10.1017/s0950268809002337] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In 2006, in The Netherlands, an outbreak of Salmonella Typhimurium phage type 561 (STM DT7, corresponding to the rare DT7 in the international typing scheme) was detected, accumulating to over 200 cases. By telephone interviews, data were collected from all laboratory-confirmed cases. In addition, in August 2006, a case-control study was performed in a subset of cases. Environmental and microbiological investigation was performed on a suspected dairy farm. In the case-control study (51 cases, 105 matched controls), hard cheese purchased from a farm, specifically farm X, and from a market stall were found to be associated with infection. The dairy production room of farm X tested STM DT7-positive in August. However, it was only in November, after earlier unsuccessful attempts, that a low-level contamination was confirmed in the hard farmhouse cheese, triggering control measures. A timely and adequate response was hampered during this outbreak for several reasons. Measures for improvement in handling future similar incidents are discussed.
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Prevalence and characterization of salmonellae in commercial ground beef in the United States. Appl Environ Microbiol 2009; 75:1892-900. [PMID: 19201965 DOI: 10.1128/aem.02530-08] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Commercially produced ground beef samples (n = 4,136) were collected from seven regions of the United States over a 24-month period (July 2005 to June 2007) and analyzed for the presence of Salmonella enterica by using methods that concurrently provided total prevalence and enumerable levels. The overall prevalence of Salmonella strains was 4.2%. Enumeration showed that 94.2% were present at levels below 2 CFU/g. Regional monthly prevalences of Salmonella strains varied from 1.8% to 6.5% but were not statistically different (P > 0.05). All Salmonella isolates were serotyped and their antibiotic susceptibilities determined and analyzed by pulsed-field gel electrophoresis (PFGE). The most common serotypes identified were Salmonella enterica serotypes Montevideo, Anatum, Muenster, and Mbandaka, with these accounting for one-half of the isolates obtained. The prevalence of multidrug-resistant (MDR) Salmonella was determined to be 0.6%. The most common MDR serotypes were Salmonella enterica serotypes Dublin, Reading, and Typhimurium. MDR strains had resistance to between 2 and 10 antibiotics. There were no regional differences in prevalence of MDR Salmonella. PFGE analysis revealed that indistinguishable XbaI and AvrII restriction digest patterns (RDPs) could be observed in isolates of the same serotype found in different regions and months of sampling. The RDPs of 19 Salmonella strains were compared to RDPs in the PulseNet USA database. Thirteen were indistinguishable from existing patterns, and the number of records for each ranged from 1 to 478. These data show that Salmonella prevalence in commercial ground beef is low and suggest that attempts to identify sources contributing to Salmonella in ground beef by serotype, antibiogram, and PFGE cannot be made without additional documented evidence.
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Pezzoli L, Elson R, Little CL, Yip H, Fisher I, Yishai R, Anis E, Valinsky L, Biggerstaff M, Patel N, Mather H, Brown DJ, Coia JE, van Pelt W, Nielsen EM, Ethelberg S, de Pinna E, Hampton MD, Peters T, Threlfall J. Packed withSalmonella—Investigation of an International Outbreak ofSalmonellaSenftenberg Infection Linked to Contamination of Prepacked Basil in 2007. Foodborne Pathog Dis 2008; 5:661-8. [DOI: 10.1089/fpd.2008.0103] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Lorenzo Pezzoli
- European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Control (ECDC), Stockholm, Sweden
- Centre for Infections, Health Protection Agency, London, United Kingdom
| | - Richard Elson
- Centre for Infections, Health Protection Agency, London, United Kingdom
| | | | - Hopi Yip
- Centre for Infections, Health Protection Agency, London, United Kingdom
| | - Ian Fisher
- Centre for Infections, Health Protection Agency, London, United Kingdom
| | - Ruth Yishai
- Molecular Biology Lab, Central Laboratories, Ministry of Health, Jerusalem, Israel
| | - Emilia Anis
- Department of Infectious Diseases, Ministry of Health, Jerusalem, Israel
| | - Lea Valinsky
- Molecular Biology Lab, Central Laboratories, Ministry of Health, Jerusalem, Israel
| | | | - Nehal Patel
- Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Henry Mather
- Scottish Salmonella Reference Laboratory, Stobhill Hospital, Glasgow, Scotland
| | - Derek J. Brown
- Scottish Salmonella Reference Laboratory, Stobhill Hospital, Glasgow, Scotland
| | - John E. Coia
- Scottish Salmonella Reference Laboratory, Stobhill Hospital, Glasgow, Scotland
| | - Wilfrid van Pelt
- Centre for Infectious Disease Control (CIb/EPI), National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Eva M. Nielsen
- Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark
| | - Steen Ethelberg
- Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark
- Department of Epidemiology, Statens Serum Institut, Copenhagen, Denmark
| | | | | | - Tansy Peters
- Centre for Infections, Health Protection Agency, London, United Kingdom
| | - John Threlfall
- Centre for Infections, Health Protection Agency, London, United Kingdom
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Nygård K, Lassen J, Vold L, Andersson Y, Fisher I, Löfdahl S, Threlfall J, Luzzi I, Peters T, Hampton M, Torpdahl M, Kapperud G, Aavitsland P. Outbreak of Salmonella Thompson infections linked to imported rucola lettuce. Foodborne Pathog Dis 2008; 5:165-73. [PMID: 18361685 DOI: 10.1089/fpd.2007.0053] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
On November 15, 2004, a cluster of three cases of Salmonella Thompson infection was registered by the Norwegian reference laboratory. In the following days further cases occurred, prompting a case-control study among the first 13 cases and 26 matched controls. By December 31, 21 cases had been reported, with the first onset on October 24. Consumption of rucola lettuce (Eruca sativa, also known as rocket salad or arugula) (OR 8,8 [1,2-infinity]) and mixed salad (OR 5,0 [1,0-infinity]) was associated with illness. On November 26, Swedish authorities notified the finding of Salmonella Thompson in rucola lettuce through the EU Rapid Alert System for Food and Feed. Later, several countries reported finding this and other Salmonella serovars and Campylobacter in rucola produced in Italy. In response to our alert through the international Enter-net surveillance network, Sweden and England also reported an increase of cases. Salmonella Thompson isolates from products and patients from several countries showed high similarity by pulsed-field gel electrophoresis, but some isolates showed significant differences. We think that the outbreak in Norway reflected a larger international outbreak caused by rucola imported from one Italian producer. Findings of other pathogens indicate a massive contamination, possibly caused by irrigation with nonpotable water. Rapid international information exchange is invaluable when investigating outbreaks caused by internationally marketed products.
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Affiliation(s)
- Karin Nygård
- Norwegian Institute of Public Health, Oslo, Norway.
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30
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Valdezate S, Arroyo M, González-Sanz R, Ramíro R, Herrera-León S, Usera MA, De la Fuente M, Echeita A. Antimicrobial resistance and phage and molecular typing of Salmonella strains isolated from food for human consumption in Spain. J Food Prot 2007; 70:2741-8. [PMID: 18095425 DOI: 10.4315/0362-028x-70.12.2741] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The aims of this study were to ascertain the population structure and antimicrobial susceptibility of Salmonella enterica serovars isolated in 2002 from food in 16 Spanish regions. Serovars were characterized by serotyping, phage typing, antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE) typing, and 264 nonrelated strains were selected for further analysis. The main sources were eggs and their derivatives (21.6% of strains), poultry and related products (16.6%), and seafood (16.3%). High serotype diversity was detected (51 serotypes); the most common were Enteritidis (n = 96, 36.3%) and Typhimurium (n = 53, 20.1%), followed by a miscellaneous group of 49 different serotypes (n = 115, 43.5%). A 15% increase in Salmonella Enteritidis isolation was observed. Common phage types for Salmonella Enteritidis were PT1 (41.6% of isolates), PT4 (9.4%), PT6 (9.4%), and PT6a (9.4%), and common types for Salmonella Typhimurium were DTU302 (18.8%), DT104 (15.1%), and DT104B (13.2%). Salmonella Enteritidis strains were categorized into eight PFGE types with a similarity of 81 to 96%, and 73.9% of the strains were grouped into just one cluster. Salmonella Typhimurium isolates were divided into 13 PFGE types with a similarity of 64 to 86%, and one predominant clone contained 41.5% of the strains. Resistance rates for Salmonella Enteritidis, Salmonella Typhimurium, and the miscellaneous group were, respectively, 8.3, 69.8, and 13.9% for ampicillin, 3.1, 52.8, and 59% for streptomycin, 40.6, 22.6, and 10.4% for nalidixic acid, 15.6, 71.7, and 31.1% for tetracycline, 7.3, 18.8, and 9.5% for trimethoprim-sulfamethoxazole, 0, 50.9, and 4.3% for chloramphenicol, and 6.2, 71.7, and 17.4% for multiple (at least four) antimicrobials. All the strains remained susceptible to other beta-lactams and fluoroquinolones. Surveillance of S. enterica isolated from food is strongly recommended to reduce community exposure to antimicrobial resistant strains.
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Affiliation(s)
- S Valdezate
- Spanish Reference Laboratory for Salmonella and Shigella, Servicio de Bacteriología, C.N.M. Instituto de Salud Carlos III, Majadahonda, Madrid 28220, Spain.
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Kérouanton A, Marault M, Lailler R, Weill FX, Feurer C, Espié E, Brisabois A. Pulsed-Field Gel Electrophoresis Subtyping Database for FoodborneSalmonella entericaSerotype Discrimination. Foodborne Pathog Dis 2007; 4:293-303. [PMID: 17883313 DOI: 10.1089/fpd.2007.0090] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Nontyphoid Salmonella is one of the main causes of bacterial gastroenteritis worldwide and is responsible for 65% of reported outbreaks of foodborne diseases in France. Serotyping is widely used for isolate preliminary identification, but it poorly discriminates strains. Rapid, efficient molecular subtyping tools have therefore been developed for the investigation of outbreaks. We evaluated the performance of the pulsed-field gel electrophoresis (PFGE) method for discrimination of 31 Salmonella serotypes frequently isolated in France. We set up a genomic database of Salmonella strains isolated from food, animals, the environment, and humans to improve the management of contamination and reactions to foodborne disease outbreaks. We studied 1128 isolates by PFGE, according to the standardized PulseNet protocol. We identified 452 PFGE patterns, 67.5% of which corresponded to a single isolate. The ability of this method to distinguish between isolates was estimated by calculating the Simpson index and the 95% confidence interval. Values obtained ranged between 0.33 (0.11-0.54) to 0.99 (0.96-1.00), depending on serotype. Epidemiological information about isolates was used for analyses of intra- and interserotype diversity results and for determining whether PFGE patterns were linked to the source of the isolate. Clustering analysis of the PFGE patterns obtained confirmed that serotype and PFGE genotype were closely linked. Some PFGE patterns were identified as major patterns, each of these patterns being found in at least 10 isolates. The database generated has already proved its effectiveness in epidemiological investigations in livestock production and foodborne outbreaks.
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Affiliation(s)
- Annaëlle Kérouanton
- Agence Française de Sécurité Sanitaire des Aliments, Laboratoire d'Etudes et de Recherches sur la Qualité des Aliments et sur les Procédés Agro-alimentaires, Unité Caractérisation et Epidémiologie Bactérienne, Maisons-Alfort, France.
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Kivi M, Hofhuis A, Notermans DW, Wannet WJB, Heck MEOC, Van De Giessen AW, Van Duynhoven YTHP, Stenvers OFJ, Bosman A, Van Pelt W. A beef-associated outbreak of Salmonella Typhimurium DT104 in The Netherlands with implications for national and international policy. Epidemiol Infect 2007; 135:890-9. [PMID: 17326850 PMCID: PMC2870660 DOI: 10.1017/s0950268807007972] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2006] [Indexed: 11/06/2022] Open
Abstract
A ten-fold increase in Salmonella Typhimurium DT104 cases in The Netherlands during September-November 2005 prompted an outbreak investigation. A population-based matched case-control study included 56 cases and 100 controls. Risk factors for infection were consumption of a pre-processed raw beef product (odds ratio 4.2, 95% confidence interval 1.5-12.0) and of food from mobile caterers (odds ratio 4.9, 95% confidence interval 1.1-22.1). Bacterial molecular typing established a link with another DT104 outbreak in Denmark caused by beef from a third European country. The incriminated beef was traced in The Netherlands and sampling yielded DT104 of the outbreak-associated molecular type. We concluded that this outbreak was caused by imported contaminated beef. Consumers should be informed about presence of raw meat in pre-processed food products. Optimal utilization of international networks and testing and traceability of foodstuffs has the potential to prevent foodborne infections.
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Affiliation(s)
- M Kivi
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, The Netherlands.
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Torpdahl M, Sørensen G, Lindstedt BA, Nielsen EM. Tandem repeat analysis for surveillance of human Salmonella Typhimurium infections. Emerg Infect Dis 2007; 13:388-95. [PMID: 17552091 PMCID: PMC2725892 DOI: 10.3201/eid1303.060460] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Multiple-locus variable-number tandem repeats analysis improves surveillance and outbreak investigations. In Denmark, as part of the national laboratory-based surveillance system of human enteric infections, all Salmonella Typhimurium isolates are currently subtyped by using phage typing, antimicrobial resistance profiles, and pulsed-field gel electrophoresis (PFGE). We evaluated the value of real-time typing that uses multiple-locus-number tandem-repeats analysis (MLVA) of Salmonella enterica serotype Typhimurium (S. Typhimurium) to detect possible outbreaks. Because only a few subtypes identified by PFGE and phage typing account for most infections, we included MLVA typing in the routine surveillance in a 2-year period beginning December 2003. The 1,019 typed isolates were separated into 148 PFGE types and 373 MLVA types. Several possible outbreaks were detected and confirmed. MLVA was particularly valuable for discriminating within the most common phage types. MLVA was superior to PFGE for both surveillance and outbreak investigations of S. Typhimurium.
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Affiliation(s)
- Mia Torpdahl
- Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark.
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Hopkins KL, Maguire C, Best E, Liebana E, Threlfall EJ. Stability of multiple-locus variable-number tandem repeats in Salmonella enterica serovar typhimurium. J Clin Microbiol 2007; 45:3058-61. [PMID: 17609320 PMCID: PMC2045244 DOI: 10.1128/jcm.00715-07] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Variable-number tandem repeats (VNTRs) may evolve so rapidly that multiple profiles emerge during an outbreak. A total of 190 isolates from eight Salmonella enterica serovar Typhimurium outbreaks and 15 isolates from seven patients were analyzed by pulsed-field gel electrophoresis and VNTR typing. Small changes in loci were noted; otherwise, the VNTR profiles were stable during the course of the outbreaks.
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Affiliation(s)
- K L Hopkins
- Laboratory of Enteric Pathogens, Health Protection Agency Centre for Infections, London, United Kingdom.
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Cooke FJ, Wain J, Fookes M, Ivens A, Thomson N, Brown DJ, Threlfall EJ, Gunn G, Foster G, Dougan G. Prophage sequences defining hot spots of genome variation in Salmonella enterica serovar Typhimurium can be used to discriminate between field isolates. J Clin Microbiol 2007; 45:2590-8. [PMID: 17522270 PMCID: PMC1951247 DOI: 10.1128/jcm.00729-07] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Sixty-one Salmonella enterica serovar Typhimurium isolates of animal and human origin, matched by phage type, antimicrobial resistance pattern, and place of isolation, were analyzed by microbiological and molecular techniques, including pulsed-field gel electrophoresis (PFGE) and plasmid profiling. PFGE identified 10 profiles that clustered by phage type and antibiotic resistance pattern with human and animal isolates distributed among different PFGE profiles. Genomic DNA was purified from 23 representative strains and hybridized to the composite Salmonella DNA microarray, and specific genomic regions that exhibited significant variation between isolates were identified. Bioinformatic analysis showed that variable regions of DNA were associated with prophage-like elements. Subsequently, simple multiplex PCR assays were designed on the basis of these variable regions that could be used to discriminate between S. enterica serovar Typhimurium isolates from the same geographical region. These multiplex PCR assays, based on prophage-like elements and Salmonella genomic island 1, provide a simple method for identifying new variants of S. enterica serovar Typhimurium in the field.
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Affiliation(s)
- Fiona J Cooke
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, United Kingdom.
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Peters TM, Berghold C, Brown D, Coia J, Dionisi AM, Echeita A, Fisher IST, Gatto AJ, Gill N, Green J, Gerner-Smidt P, Heck M, Lederer I, Lukinmaa S, Luzzi I, Maguire C, Prager R, Usera M, Siitonen A, Threlfall EJ, Torpdahl M, Tschäpe H, Wannet W, Zwaluw WKVD. Relationship of pulsed-field profiles with key phage types of Salmonella enterica serotype Enteritidis in Europe: results of an international multi-centre study. Epidemiol Infect 2007; 135:1274-81. [PMID: 17306053 PMCID: PMC2870705 DOI: 10.1017/s0950268807008102] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Salmonella is one of the most common causes of foodborne infection in Europe with Salmonella enterica serovar Enteritidis (S. Enteritidis) being the most commonly identified serovar. The predominant phage type for S. Enteritidis is phage type (PT) 4, although PT 8 has increased in incidence. Within these phage types, pulsed-field gel electrophoresis (PFGE) provides a method of further subdivision. The international project, Salm-gene, was established in 2001 to develop a database of PFGE profiles within nine European countries and to establish criteria for real-time pattern recognition. It uses DNA fingerprints of salmonellas to investigate outbreaks and to evaluate trends and emerging issues of foodborne infection within Europe. The Salm-gene database contains details of about 11 700 S. Enteritidis isolates, demonstrating more than 65 unique PFGE profiles. The clonal nature of S. Enteritidis is evidenced by the high similarity and distribution of PFGE profiles. Over 56% (6603/11 716) of the submitted isolates of several different phage types were profile SENTXB.0001, although this profile is most closely associated with PT 4. The next most common profiles, SENTXB.0002 and SENTXB.0005, were closely associated with PT 8 and PT 21 respectively. Studies to investigate the relationship of profile types with outbreaks and possible vehicles of infection suggest that the incidence of PFGE profile SENTXB.0002, and thus PT 8, in some countries may be due to importation of foods or food production animals from Eastern Europe, where PT 8 is amongst the most frequently identified phage types. Collation of subtyping data, especially in the commonly recognized phage types, is necessary in order to evaluate trends and emerging issues in salmonella infection.
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Affiliation(s)
- T M Peters
- Health Protection Agency, Centre for Infections, London, UK.
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Giammanco GM, Mammina C, Romani C, Luzzi I, Dionisi AM, Nastasi A. Evaluation of a modified single-enzyme amplified fragment length polymorphism (SE-AFLP) technique for subtyping Salmonella enterica serotype Enteritidis. Res Microbiol 2006; 158:10-7. [PMID: 17224257 DOI: 10.1016/j.resmic.2006.10.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Revised: 09/23/2006] [Accepted: 10/09/2006] [Indexed: 11/19/2022]
Abstract
Salmonella enterica subsp. enterica serotype Enteritidis is not readily subtyped beyond the level of phage type (PT). Pulsed field gel electrophoresis (PFGE) is generally acknowledged to be the most discriminating typing method for Salmonella, but only a restricted variety of PFGE types has been described for S. enterica serotype Enteritidis. In the present study, a modification of the SE-AFLP typing method was used to investigate both outbreak and apparently sporadic isolates of S. enterica serotype Enteritidis belonging to different PTs and/or PFGE types. The method proved to be as discriminatory as PFGE when combined with phage typing, and provided subtyping data consistent with epidemiological information. Although the modified SE-AFLP typing method did not prove to achieve a superior discriminatory ability in resolving clusters, it has a high enough throughput for use in outbreak investigations. This method can be used in combination with other typing methods to obtain epidemiologically relevant subtyping data on S. enterica serotype Enteritidis.
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Affiliation(s)
- Giovanni M Giammanco
- Dipartimento di Igiene e Microbiologia G. D'Alessandro, Università degli Studi di Palermo, via del Vespro 133, 90127 Palermo, Italy.
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