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Yu D, Liang Y, Lu Q, Meng Q, Wang W, Huang L, Bao Y, Zhao R, Chen Y, Zheng Y, Yang Y. Molecular Characteristics of Streptococcus pyogenes Isolated From Chinese Children With Different Diseases. Front Microbiol 2021; 12:722225. [PMID: 34956108 PMCID: PMC8696671 DOI: 10.3389/fmicb.2021.722225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 11/11/2021] [Indexed: 11/13/2022] Open
Abstract
Streptococcus pyogenes is a bacterial pathogen that causes a wide spectrum of clinical diseases exclusively in humans. The distribution of emm type, antibiotic resistance and virulence gene expression for S. pyogenes varies temporally and geographically, resulting in distinct disease spectra. In this study, we analyzed antibiotic resistance and resistance gene expression patterns among S. pyogenes isolates from pediatric patients in China and investigated the relationship between virulence gene expression, emm type, and disease categories. Forty-two representative emm1.0 and emm12.0 strains (n = 20 and n = 22, respectively) isolated from patients with scarlet fever or obstructive sleep apnea-hypopnea syndrome were subjected to whole-genome sequencing and phylogenetic analysis. These strains were further analyzed for susceptibility to vancomycin. We found a high rate and degree of resistance to macrolides and tetracycline in these strains, which mainly expressed ermB and tetM. The disease category correlated with emm type but not superantigens. The distribution of vanuG and virulence genes were associated with emm type. Previously reported important prophages, such as φHKU16.vir, φHKU488.vir, Φ5005.1, Φ5005.2, and Φ5005.3 encoding streptococcal toxin, and integrative conjugative elements (ICEs) such as ICE-emm12 and ICE-HKU397 encoding macrolide and tetracycline resistance were found present amongst emm1 or emm12 clones from Shenzhen, China.
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Affiliation(s)
- Dingle Yu
- Microbiology Laboratory, National Center for Children's Health, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China.,Shenzhen Children's Hospital, Shenzhen, China
| | - Yunmei Liang
- Beijing Chaoyang Hospital Affiliated to the Capital Medical University, Beijing, China
| | - Qinghua Lu
- Microbiology Laboratory, National Center for Children's Health, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China.,Shenzhen Children's Hospital, Shenzhen, China
| | - Qing Meng
- Shenzhen Children's Hospital, Shenzhen, China
| | | | - Lu Huang
- Shenzhen Children's Hospital, Shenzhen, China
| | - Yanmin Bao
- Shenzhen Children's Hospital, Shenzhen, China
| | | | | | | | - Yonghong Yang
- Microbiology Laboratory, National Center for Children's Health, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China.,Shenzhen Children's Hospital, Shenzhen, China
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Epidemiological analysis of Group A Streptococcus infections in a hospital in Beijing, China. Eur J Clin Microbiol Infect Dis 2020; 39:2361-2371. [PMID: 32676802 DOI: 10.1007/s10096-020-03987-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/06/2020] [Indexed: 02/07/2023]
Abstract
Our study aimed to investigate the epidemiological and molecular characteristics of isolates collected from Group A Streptococcus (GAS) infections in children in Beijing China during the year 2019. Emm typing, superantigens, and erythromycin resistance genotypes were determined by PCR. Antimicrobial susceptibility testing was performed as recommended by Clinical Laboratory Standards Institute (CLSI). A total of 271 GAS isolates were collected. Thirteen different emm types, including 31 subtypes, were identified. The most prevalent emm types were emm12 (52.77%), emm1 (36.9%), emm3.1 (2.95%), and emm75.0 (2.95%). Two variant subtypes, STC36.0 and STG840.2, were identified. There was no difference in the portion of emm12 and emm1 isolates in scarlet fever, impetigo, and psoriasis. The majority of superantigens detected were smeZ (94.46%), speC (91.14%), and ssa (74.91%), followed by speH (56.46%), speI (45.76%), speJ (36.9%), and speA (34.32%). More scarlet fever isolates harbored speA (35.6%) and speJ (38.4%), more psoriasis isolates harbored speI (57.9%), and more impetigo isolates harbored ssa (89.7%). Isolates were universally susceptible to penicillin and resistant to erythromycin (94.83%). Moreover, 89.67% erythromycin resistance isolates harbored the ermB gene. The erythromycin resistance rate of the isolates from the three diseases was different. Scarlet fever is the common streptococcal infectious disease in dermatology. Emm12 and emm1 were the most prevalent emm types. The most prevalent superantigens detected were smeZ, spec, and ssa. There is association between diversity of superantigens and disease manifestation. Hence, continuous surveillance of GAS molecular epidemiological characterizations in different diseases is needed.
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Li H, Zhou L, Zhao Y, Ma L, Liu X, Hu J. Molecular epidemiology and antimicrobial resistance of group a streptococcus recovered from patients in Beijing, China. BMC Infect Dis 2020; 20:507. [PMID: 32660436 PMCID: PMC7359455 DOI: 10.1186/s12879-020-05241-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 07/07/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Group A streptococcus (GAS) is an important human pathogen responsible for a broad range of infections. Epidemiological surveillance has been crucial to detect changes in the geographical and temporal variation of the disease pattern. The objective of this study was to investigate the molecular epidemiological characteristics and antimicrobial resistance of GAS isolates from patients in Children's Hospital in Beijing. METHODS From 2016 to 2017, pharyngeal swab samples were collected from the outpatients in Children's Hospital, Capital Institute of Pediatrics, who were diagnosed with scarlet fever. Antimicrobial susceptibility test was performed according to the distribution of conventional antibiotics and Clinical and Laboratory Standards Institute (CLSI) recommendations. The distribution of the macrolide-resistance genes (ermB, ermA, mefA), emm (M protein-coding gene) typing, and superantigens (SAg) gene profiling were examined by polymerase chain reaction (PCR). RESULTS A total of 297 GAS isolates were collected. The susceptibility of the isolates to penicillin, ceftriaxone, and levofloxacin was 100%. The resistance rate to erythromycin and clindamycin was 98.3 and 96.6%, respectively. The dominant emm types were emm12 (65.32%), emm1 (27.61%), emm75 (2.69%), and emm89 (1.35%). Of the 297 isolates, 290 (97.64%) carried the ermB gene, and 5 (1.68%) carried the mefA gene, while none carried the ermA gene. The most common superantigen genes identified from GAS isolates were smeZ (96.97%), speC (92.59%), speG (91.58%), ssa (85.52%), speI (54.55%), speH (52.19%), and speA (34.34%). Isolates with the genotype emm1 possessed speA, speC, speG, speJ, speM, ssa, and smeZ, while emm12 possessed speC, speG, speH, speI, speM, ssa, and smeZ superantigens. CONCLUSIONS The prevalent strain of GAS isolates in Beijing has a high resistance rate to macrolides; however, penicillin can still be the preferred antibiotic for treatment. Erythromycin resistance was predominantly mediated by ermB. The common emm types were emm12 and emm1. There was a correlation between emm and the superantigen gene. Thus, long-term monitoring and investigation of the emm types and superantigen genes of GAS prevalence are imperative.
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Affiliation(s)
- Hongxin Li
- Department of Dermatology, Children's Hospital Affiliated to Capital Institute of Pediatrics, Beijing, 100020, China.
| | - Lin Zhou
- Department of Clinical Laboratory, Children's Hospital Affiliated to Capital Institute of Pediatrics, Beijing, 100020, China
| | - Yong Zhao
- The Sixth Medical Centre of PLA, General Hospital, Beijing, 100048, China
| | - Lijuan Ma
- Department of Clinical Laboratory, Children's Hospital Affiliated to Capital Institute of Pediatrics, Beijing, 100020, China
| | - Xiaoyan Liu
- Department of Dermatology, Children's Hospital Affiliated to Capital Institute of Pediatrics, Beijing, 100020, China
| | - Jin Hu
- Department of Dermatology, Children's Hospital Affiliated to Capital Institute of Pediatrics, Beijing, 100020, China.
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Changes in M types of Streptococcus pyogenes in Chinese children with scarlet fever. THE LANCET. INFECTIOUS DISEASES 2020; 20:780. [PMID: 32592668 DOI: 10.1016/s1473-3099(20)30441-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 05/19/2020] [Indexed: 11/21/2022]
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Altun M, Mericli Yapıcı B. Detection of Group A Beta Hemolytic Streptococci Species, emm, and Exotoxin Genes Isolated from Patients with Tonsillopharyngitis. Curr Microbiol 2020; 77:2064-2070. [PMID: 32367278 PMCID: PMC7222056 DOI: 10.1007/s00284-020-01994-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 04/10/2020] [Indexed: 10/25/2022]
Abstract
Group A Beta Hemolytic Streptococci (GAS) is the most critical human pathogen that leads to tonsillopharyngitis. The aims of this study were to identify GAS isolates and to determine emm typing, the coverage rate of available vaccines, and the distribution of superantigen gene profiles. 15 GAS isolates were isolated from throat cultures of 200 patients with tonsillopharyngitis, who were admitted to Canakkale Health Application and Research Hospital between October 2017 and May 2018. Identification of the isolates was performed by conventional methods and 16S rRNA sequence analysis. emm typing and exotoxin profiling of the isolates were performed by polymerase chain reaction. 7.5% GAS was detected in 200 patients. All the GAS isolates were identified as S. pyogenes. emm typing can be carried out in 13 S. pyogenes isolates. emm89 (33.3%), emm44 (20%), emm6 (13.3%), emm84 (6.7%), emm1 (6.7%), and emm18.1 (6.7%) were found to be six emm types. The coverage rate of S. pyogenes strains for 26-valent vaccine was 61.5% and for the 30-valent vaccine 84.6%. The most common exotoxin was speB (86.7%), followed by speC (60%), speF (33.3%), ssa (26.7%), speA (20%), speM (20%), speJ (13.3%), speL (6.7%), and speI (6.7%). As a result of determining the emm types of S. pyogenes species in Canakkale, it was concluded that the potential of 30-valent vaccine should be considered in Turkey and development of vaccines containing exotoxin types may be beneficial.
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Affiliation(s)
- Mehzat Altun
- Vocational School of Health Services, Canakkale Onsekiz Mart University, Canakkale, Turkey
| | - Binnur Mericli Yapıcı
- Department of Biology, Faculty of Sciences and Arts, Canakkale Onsekiz Mart University, 17020, Canakkale, Turkey.
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Freschi de Barros S, De Amicis KM, Alencar R, Smeesters PR, Trunkel A, Postól E, Almeida Junior JN, Rossi F, Pignatari ACC, Kalil J, Guilherme L. Streptococcus pyogenes strains in Sao Paulo, Brazil: molecular characterization as a basis for StreptInCor coverage capacity analysis. BMC Infect Dis 2015; 15:308. [PMID: 26243278 PMCID: PMC4525746 DOI: 10.1186/s12879-015-1052-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 07/22/2015] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Several human diseases are caused by Streptococcus pyogenes, ranging from common infections to autoimmunity. Characterization of the most prevalent strains worldwide is a useful tool for evaluating the coverage capacity of vaccines under development. In this study, a collection of S. pyogenes strains from Sao Paulo, Brazil, was analyzed to describe the diversity of strains and assess the vaccine coverage capacity of StreptInCor. METHODS Molecular epidemiology of S. pyogenes strains was performed by emm-genotyping the 229 isolates from different clinical sites, and PCR was used for superantigen profile analysis. The emm-pattern and tissue tropism for these M types were also predicted and compared based on the emm-cluster classification. RESULTS The strains were fit into 12 different emm-clusters, revealing a diverse phylogenetic origin and, consequently, different mechanisms of infection and escape of the host immune system. Forty-eight emm-types were distinguished in 229 samples, and the 10 most frequently observed types accounted for 69 % of all isolates, indicating a diverse profile of circulating strains comparable to other countries under development. A similar proportion of E and A-C emm-patterns were observed, whereas pattern D was less frequent, indicating that the strains of this collection primarily had a tissue tropism for the throat. In silico analysis of the coverage capacity of StreptInCor, an M protein-conserved regionally based vaccine candidate developed by our group, had a range of 94.5 % to 59.7 %, with a mean of 71.0 % identity between the vaccine antigen and the predicted amino acid sequence of the emm-types included here. CONCLUSIONS This is the first report of S. pyogenes strain characterization in Sao Paulo, one of the largest cities in the world; thus, the strain panel described here is a representative sample for vaccine coverage capacity analysis. Our results enabled evaluation of StreptInCor candidate vaccine coverage capacity against diverse M-types, indicating that the vaccine candidate likely would induce protection against the diverse strains worldwide.
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Affiliation(s)
- Samar Freschi de Barros
- Heart Institute (InCor), School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
- Institute for Immunology Investigation, National Institute of Science and Technology, Sao Paulo, 01246-000, Brazil.
| | - Karine Marafigo De Amicis
- Heart Institute (InCor), School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
- Institute for Immunology Investigation, National Institute of Science and Technology, Sao Paulo, 01246-000, Brazil.
| | - Raquel Alencar
- Heart Institute (InCor), School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
- Institute for Immunology Investigation, National Institute of Science and Technology, Sao Paulo, 01246-000, Brazil.
| | - Pierre Robert Smeesters
- Laboratoire de Génétique et Physiologie Bactérienne, Institute de Biologie et de Médecine Moléculaires, Faculté des Sciences, Université Libre de Bruxelles, Bruxelles, 1050, Belgium.
- Murdoch Childrens Research Institute, Parkville, 3052, Australia.
| | - Ariel Trunkel
- Heart Institute (InCor), School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
- Institute for Immunology Investigation, National Institute of Science and Technology, Sao Paulo, 01246-000, Brazil.
| | - Edilberto Postól
- Heart Institute (InCor), School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
- Institute for Immunology Investigation, National Institute of Science and Technology, Sao Paulo, 01246-000, Brazil.
| | - João Nóbrega Almeida Junior
- Microbiology Laboratory of Clinical Hospital, School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
| | - Flavia Rossi
- Microbiology Laboratory of Clinical Hospital, School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
| | | | - Jorge Kalil
- Heart Institute (InCor), School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
- Institute for Immunology Investigation, National Institute of Science and Technology, Sao Paulo, 01246-000, Brazil.
- Clinical Immunology and Allergy Division, School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
| | - Luiza Guilherme
- Heart Institute (InCor), School of Medicine, University of Sao Paulo, Sao Paulo, 01246-000, Brazil.
- Institute for Immunology Investigation, National Institute of Science and Technology, Sao Paulo, 01246-000, Brazil.
- Laboratory of Immunology, Clinical Hospital, Heart Institute (HC-FMUSP), Av. Dr. Enéas de Carvalho Aguiar, 44, Sao Paulo, 05403-000, Brazil.
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Molecular typing of Chinese Streptococcus pyogenes isolates. Mol Cell Probes 2015; 29:172-6. [PMID: 25843529 DOI: 10.1016/j.mcp.2015.03.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 03/03/2015] [Accepted: 03/25/2015] [Indexed: 11/22/2022]
Abstract
Streptococcus pyogenes causes human infections ranging from mild pharyngitis and impetigo to serious diseases including necrotizing fasciitis and streptococcal toxic shock syndrome. The objective of this study was to compare molecular emm typing and pulsed field gel electrophoresis (PFGE) with multiple-locus variable-number tandem-repeat analysis (MLVA) for genotyping of Chinese S. pyogenes isolates. Molecular emm typing and PFGE were performed using standard protocols. Seven variable number tandem repeat (VNTR) loci reported in a previous study were used to genotype 169 S. pyogenes geographically-diverse isolates from China isolated from a variety of disease syndromes. Multiple-locus variable-number tandem-repeat analysis provided greater discrimination between isolates when compared to emm typing and PFGE. Removal of a single VNTR locus (Spy2) reduced the sensitivity by only 0.7%, which suggests that Spy2 was not informative for the isolates screened. The results presented support the use of MLVA as a powerful epidemiological tool for genotyping S. pyogenes clinical isolates.
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Karaky NM, Araj GF, Tokajian ST. Molecular characterization of Streptococcus pyogenes group A isolates from a tertiary hospital in Lebanon. J Med Microbiol 2014; 63:1197-1204. [PMID: 24980572 DOI: 10.1099/jmm.0.063412-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Streptococcus pyogenes [Group A Streptococcus (GAS)] is one of the most important human pathogens, responsible for numerous diseases with diverse clinical manifestations. As the epidemiology of GAS infections evolves, a rapid and reliable characterization of the isolates remains essential for epidemiological analysis and infection control. This study investigated the epidemiological patterns and genetic characteristics of 150 GAS isolates from a tertiary hospital in Lebanon by emm typing, superantigens (SAgs) detection, PFGE and antibiotic profiling. The results revealed 41 distinct emm types, the most prevalent of which were emm89 (16 %), emm12 (10 %), emm2 (9 %) and emm1 (8 %). Testing for the presence of superantigens showed that speB (87 %), ssa (36 %) and speG (30 %) were predominant. PFGE detected 39 pulsotypes when a similarity cut-off value of 80 % was implemented. Antibiotic-susceptibility testing against seven different classes of antibiotics showed that 9 % of the isolates were resistant to clindamycin, 23 % were resistant to erythromycin and 4 % showed the macrolide-lincosamide-streptogramin B (MLSB) phenotype. The emergence of tetracycline-resistant strains (37 %) was high when compared with previous reports from Lebanon. This study provided comprehensive evidence of the epidemiology of GAS in Lebanon, highlighting the association between emm types and toxin genes, and providing valuable information about the origin and dissemination of this pathogen.
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Affiliation(s)
- Nathalie M Karaky
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos, Lebanon
| | - George F Araj
- Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Sima T Tokajian
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos, Lebanon
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Draft Genome Sequences of Streptococcus pyogenes Strains Associated with Throat and Skin Infections in Lebanon. GENOME ANNOUNCEMENTS 2014; 2:genomeA.00358-14. [PMID: 24831139 PMCID: PMC4022803 DOI: 10.1128/genomea.00358-14] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We present the draft genome sequences of nine clinical Streptococcus pyogenes isolates recovered from patients suffering from sore throat and skin infections. An average of 2,454,334 paired-end reads per sample were generated, which assembled into 21 to 198 contigs, with a G+C content of 38.4 to 38.5%.
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Yang P, Peng X, Zhang D, Wu S, Liu Y, Cui S, Lu G, Duan W, Shi W, Liu S, Li J, Wang Q. Characteristics of group A Streptococcus strains circulating during scarlet fever epidemic, Beijing, China, 2011. Emerg Infect Dis 2013; 19:909-15. [PMID: 23735582 PMCID: PMC4816378 DOI: 10.3201/eid1906.121020] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Scarlet fever is one of a variety of diseases caused by group A Streptococcus (GAS). During 2011, a scarlet fever epidemic characterized by peak monthly incidence rates 2.9–6.7 times higher than those in 2006–2010 occurred in Beijing, China. During the epidemic, hospital-based enhanced surveillance for scarlet fever and pharyngitis was conducted to determine characteristics of circulating GAS strains. The surveillance identified 3,359 clinical cases of scarlet fever or pharyngitis. GAS was isolated from 647 of the patients; 76.4% of the strains were type emm12, and 17.1% were emm1. Almost all isolates harbored superantigens speC and ssa. All isolates were susceptible to penicillin, and resistance rates were 96.1% to erythromycin, 93.7% to tetracycline, and 79.4% to clindamycin. Because emm12 type GAS is not the predominant type in other countries, wider surveillance for the possible spread of emm12 type GAS from China to other countries is warranted.
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Affiliation(s)
- Peng Yang
- Beijing Center for Disease Prevention and Control, School of Public Health and Family Medicine, Capital Medical University, Beijing, China
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Yang P, Peng X, Cui S, Shao J, Zhu X, Zhang D, Liang H, Wang Q. Development of a panel of seven duplex real-time PCR assays for detecting 13 streptococcal superantigens. Ann Clin Microbiol Antimicrob 2013; 12:18. [PMID: 23895694 PMCID: PMC3737041 DOI: 10.1186/1476-0711-12-18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 07/27/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Streptococcal superantigens (SAgs) are the major virulence factors of infection in humans for group A Streptococcus (GAS) bacteria. A panel consisting of seven duplex real-time PCR assays was developed to simultaneously detect 13 streptococcal SAgs and one internal control which may be important in the control of GAS-mediated diseases. METHODS Primer and probe sequences were selected based on the highly conserved region from an alignment of nucleotide sequences of the 13 streptococcal SAgs. The reaction conditions of the duplex real-time PCR were optimized and the specificity of the duplex assays was evaluated using SAg positive strains. The limit of detection of the duplex assays was determined by using 10-fold serial dilutions of the DNA of 13 streptococcal SAgs and compared to a conventional polymerase chain reaction (PCR) method for evaluating the duplex assays sensitivity. RESULTS Using the duplex assays, we were able to differentiate between 13 SAgs from Streptococcus strains and other non-Streptococcus bacteria without cross-reaction. On the other hand, the limit of detection of the duplex assays was at least one or two log dilutions lower than that of the conventional PCR. CONCLUSIONS The panel was highly specific (100%) and the limit of detection of these duplex groups was at least ten times lower than that obtained by using a conventional PCR method.
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Affiliation(s)
- Peng Yang
- Institute for Infectious Disease and Endemic Disease Control, Beijing Center for Disease Prevention and Control (CDC), Beijing Research Center for Preventive Medicine, Capital Medical University School of Public Health, No,16 He Pingli Middle Street, Dongcheng District, Beijing 100013, China
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Draft genome sequences of two Streptococcus pyogenes strains involved in abnormal sharp raised scarlet fever in China, 2011. J Bacteriol 2013; 194:5983-4. [PMID: 23045496 DOI: 10.1128/jb.01474-12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A scarlet fever outbreak caused by Streptococcus pyogenes occurred in China in 2011. To determine the genomic features of the outbreak strains, we deciphered genomes of two strains isolated from the regions with the highest incidence rates. The sequences will provide valuable information for comprehensive study of mechanisms related to this outbreak.
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Outbreak of scarlet fever associated with emm12 type group A Streptococcus in 2011 in Shanghai, China. Pediatr Infect Dis J 2012; 31:e158-62. [PMID: 22531238 DOI: 10.1097/inf.0b013e31825874f3] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND An unprecedented, large outbreak of childhood scarlet fever occurred in Shanghai between April and July 2011. Investigation of the epidemiology could enhance our understanding of the factors related to the outbreak. METHODS We retrospectively analyzed the demographic and seasonal characteristics of children with scarlet fever and the outcome. During the peak month of the 2011 outbreak, 45 GAS isolates recovered from pediatric patients and 13 (43.3%) GAS isolates recovered from 30 asymptomatic student contacts were characterized by emm typing, superantigen profiles, pulsed-field gel electrophoresis genotypes, mutilocus sequence typing and antimicrobial susceptibility. RESULTS The 2011 outbreak of scarlet fever started in April and peaked in May and June. Boys outnumbered girls (65.1% versus 34.9%). Preschool and primary school children accounted for 96% of cases. No severe outcome was found. emm1, emm12 and emm75 were identified among 58 GAS isolates, and 53 (91.4%) isolates belonged to emm12, st36. Ten pulsed-field gel electrophoresis genotypes were identified among emm12 GAS isolates, 43 (81.1%) shared SPYS16.001 genotype and the remaining 7 genotypes detected were related to SPYS16.001 closely or possibly. No streptococcal pyrogenic exotoxin A and streptococcal pyrogenic exotoxin M were detected in 58 isolates. All emm12 GAS isolates were resistant to azithromycin and clindamycin. CONCLUSIONS emm12 GAS strain caused the large 2011 outbreak of scarlet fever in Shanghai. Antibiotic resistance to macrolides and clindamycin in GAS is prevalent in Shanghai.
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Liang Y, Liu X, Chang H, Ji L, Huang G, Fu Z, Zheng Y, Wang L, Li C, Shen Y, Yu S, Yao K, Ma L, Shen X, Yang Y. Epidemiological and molecular characteristics of clinical isolates of Streptococcus pyogenes collected between 2005 and 2008 from Chinese children. J Med Microbiol 2012; 61:975-983. [PMID: 22442290 DOI: 10.1099/jmm.0.042309-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Yunmei Liang
- Beijing Shijitan Hospital Affiliated to Capital Medical University, Beijing 100038, PR China
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Xiaorong Liu
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Hesheng Chang
- Beijing Chaoyang Hospital Affiliated to Capital Medical University, Beijing 100020, PR China
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Lili Ji
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Guoying Huang
- Children’s Hospital of Fudan University, Shanghai 200040, PR China
| | - Zhou Fu
- Chongqing Children’s Hospital Affiliated to Chongqing Medical University, Chongqing 400015, PR China
| | - Yuejie Zheng
- Shenzhen Children’s Hospital, Shenzhen 518035, PR China
| | - Libo Wang
- Children’s Hospital of Fudan University, Shanghai 200040, PR China
| | - Chengrong Li
- Shenzhen Children’s Hospital, Shenzhen 518035, PR China
| | - Ying Shen
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Sangjie Yu
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Kaihu Yao
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Lin Ma
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Xuzhuang Shen
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
| | - Yonghong Yang
- Beijing Children’s Hospital Affiliated to Capital Medical University, Beijing 100045, PR China
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Region specific and worldwide distribution of collagen-binding M proteins with PARF motifs among human pathogenic streptococcal isolates. PLoS One 2012; 7:e30122. [PMID: 22253902 PMCID: PMC3256231 DOI: 10.1371/journal.pone.0030122] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Accepted: 12/14/2011] [Indexed: 11/19/2022] Open
Abstract
Some of the variety of Streptococcus pyogenes and Streptococcus dysgalactiae ssp. equisimilis (SDSE) M proteins act as collagen-binding adhesins that facilitate acute infection. Moreover, their potential to trigger collagen autoimmunity has been implicated in the pathogenesis of acute rheumatic fever and attributed to a collagen-binding motif called PARF (peptide associated with rheumatic fever). For the first time we determine the rate of clinical isolates with collagen-binding M proteins that use a PARF motif (A/T/E)XYLXX(L/F)N in a defined geographic region, Vellore in South India. In this region both, incidence of streptococcal infections and prevalence of acute rheumatic fever are high. M proteins with PARF motif conferred collagen-binding activity to 3.9% of 153 S. pyogenes and 10.6% of 255 SDSE clinical isolates from Vellore. The PARF motif occurred in three S. pyogenes and 22 SDSE M protein types. In one of the S. pyogenes and five of the SDSE M proteins that contained the motif, collagen-binding was impaired, due to influences of other parts of the M protein molecule. The accumulated data on the collagen binding activity of certain M protein types allowed a reanalysis of published worldwide emm-typing data with the aim to estimate the rates of isolates that bind collagen via PARF. The results indicate that M proteins, which bind collagen via a PARF motif, are epidemiologically relevant in human infections, not only in Vellore. It is imperative to include the most relevant collagen-binding M types in vaccines. But when designing M protein based vaccines it should be considered that collagen binding motifs within the vaccine antigen remain potential risk factors.
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Yin J, Yu S, Liu X, Li Y, Gao W, Zhou L, Ji L, Shen X, Yang Y. Molecular characterization of group G Streptococcus dysgalactiae subsp. equisimilis recovered from patients and healthy people in China. Diagn Microbiol Infect Dis 2012; 72:41-6. [DOI: 10.1016/j.diagmicrobio.2011.09.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2011] [Revised: 09/19/2011] [Accepted: 09/23/2011] [Indexed: 11/26/2022]
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Michaelsen TE, Andreasson IKG, Langerud BK, Caugant DA. Similar superantigen gene profiles and superantigen activity in norwegian isolates of invasive and non-invasive group a streptococci. Scand J Immunol 2011; 74:423-9. [PMID: 21707691 DOI: 10.1111/j.1365-3083.2011.02594.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Group A streptococcus (GAS) harbours several virulence factors, including M protein (coded by the emm gene) and superantigens (SAgs). SAgs are extracellular toxins that directly activate the immune system by cross-binding to the HLA class II molecule and T cell receptor (TCR), thereby causing activation of up to 30% of the T cells and subsequent massive secretion of cytokines. Forty-eight GAS strains isolated from patients at Norwegian hospitals between 1988 and 2004 were included in this study. Of these, 24 were invasive streptococcal toxic shock syndrome (STSS) or necrotizing fasciitis (NF) isolates and 24 were non-invasive pharyngitis isolates, matched for having the same T-type and year of isolation as the invasive isolates. The isolates were characterized by emm sequence typing, multilocus sequence typing (MLST) and SAg gene profiles. A correlation between T-type, emm type, sequence type and SAg gene profile was revealed. No difference between invasive and non-invasive isolates regarding serotype or genotype was demonstrated. Selected invasive and non-invasive isolates with identical SAg gene profiles were analysed for SAg activity in bacterial growth culture media with and without human cell culture media added. A human T cell proliferation assay was used as measurement for SAg activity and simultaneously we also measured the cytokine content in normal human peripheral blood leucocyte cell culture media. The results revealed that invasive and non-invasive isolates did not differ significantly in SAg activity as it is present in semipurified bacterial culture medium.
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Affiliation(s)
- T E Michaelsen
- Department of Bacteriology and Immunology, Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway.
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Feng L, Lin H, Ma Y, Yang Y, Zheng Y, Fu Z, Yu S, Yao K, Shen X. Macrolide-resistant Streptococcus pyogenes from Chinese pediatric patients in association with Tn916 transposons family over a 16-year period. Diagn Microbiol Infect Dis 2010; 67:369-75. [DOI: 10.1016/j.diagmicrobio.2010.03.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 03/16/2010] [Accepted: 03/30/2010] [Indexed: 12/30/2022]
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