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Lewnard JA, Whittles LK, Rick AM, Martin JM. Naturally Acquired Protection Against Upper Respiratory Symptoms Involving Group A Streptococcus in a Longitudinal Cohort Study. Clin Infect Dis 2021; 71:e244-e254. [PMID: 31955205 DOI: 10.1093/cid/ciaa044] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 01/15/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Pharyngitis due to group A Streptococcus (GAS) represents a major cause of outpatient visits and antibiotic use in the United States. A leading vaccine candidate targets 30 of the > 200 emm types of GAS. We aimed to assess natural protection conferred by GAS against respiratory symptoms. METHODS In a 5-year study among school-aged children in Pittsburgh, Pennsylvania, pharyngeal cultures were obtained from children at 2-week intervals, and active surveillance was conducted for respiratory illnesses. We assessed protection via the relative odds of previous detection of homologous strains (defined by field-inversion gel electrophoresis banding pattern), emm types, and emm clusters at visits where GAS was detected with symptoms, vs visits where GAS was detected without symptoms. We used a cluster bootstrap of children to adjust estimates for repeated sampling. RESULTS At visits where previously detected GAS emm types were identified, we estimated 81.8% (95% confidence interval [CI], 67.1%-91.7%) protection against typical pharyngitis symptoms among children reacquiring the same strain, and 94.5% (95% CI, 83.5%-98.6%) protection among children acquiring a distinct strain. We estimated 77.1% (95% CI, 33.7%-96.3%) protection against typical symptoms among children acquiring partially heterologous emm types belonging to a previously detected emm cluster. Protection was evident after both symptomatic and asymptomatic detections of GAS. We did not identify strong evidence of protection against atypical respiratory symptoms. CONCLUSIONS Within a 5-year longitudinal study, previous detection of GAS emm types was associated with protection against typical symptoms when homologous strains were subsequently detected. Naturally acquired protection against partially heterologous types suggests that emm type-based vaccines may have broader strain coverage than what has been previously assumed.
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Affiliation(s)
- Joseph A Lewnard
- Division of Epidemiology, School of Public Health, University of California, Berkeley, Berkeley, California, USA.,Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California, USA.,Center for Computational Biology, College of Engineering, University of California, Berkeley, Berkeley, California, USA
| | - Lilith K Whittles
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, United Kingdom.,Medical Research Council Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom.,National Institute for Health Research Health Protection Research Unit in Modelling Methodology, School of Public Health, Imperial College London, London, United Kingdom
| | - Anne-Marie Rick
- Department of Pediatrics, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Department of Pediatrics, University of Pittsburgh Medical Center Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Judith M Martin
- Department of Pediatrics, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Department of Pediatrics, University of Pittsburgh Medical Center Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Fiedler T, Sugareva V, Patenge N, Kreikemeyer B. Insights into Streptococcus pyogenes pathogenesis from transcriptome studies. Future Microbiol 2011; 5:1675-94. [PMID: 21133689 DOI: 10.2217/fmb.10.128] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Streptococcus pyogenes (group A Streptococcus [GAS]) is a major human pathogen, causing diseases ranging from mild superficial infections of the skin and pharyngeal mucosal membrane, up to severe systemic and invasive diseases and autoimmune sequelae. The capability of GAS to cause this wide variety of infections is due to the expression of a large set of virulence factors, their concerted transcriptional regulation, and bacterial adaptation mechanisms to various host niches, which we are now beginning to understand on a molecular level. The addition of -omics technologies for GAS pathogenesis investigation, on top of traditional molecular methods, led to fast progress in understanding GAS pathogenesis mechanisms. This article focuses on differential transcriptional analysis performed on the bacterial side as well as on the host cell side. The microarray studies discussed provide new insight into the following five topics: gene-expression patterns under infection-relevant conditions, gene-expression patterns in mutant strains compared with wild-type strains, emergence of exceptionally fit GAS clones, gene-expression patterns of eukaryotic target and immune cells in response to GAS infection, and mechanisms underlying shifts from a pharyngeal to invasive GAS lifestyle.
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Affiliation(s)
- Tomas Fiedler
- Institute of Medical Microbiology, Virology & Hospital Hygiene, University Hospital Rostock, Schillingallee 70, Rostock, Germany
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Huang WC, Chen YYM, Teng LJ, Lien HT, Chen JY, Chia JS. Chromosomal inversion between rrn operons among Streptococcus mutans serotype c oral and blood isolates. J Med Microbiol 2008; 57:198-206. [PMID: 18201986 DOI: 10.1099/jmm.0.47428-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Streptococcus mutans causes dental caries and infective endocarditis. The aim of this study was to determine genomic diversity among serotype c S. mutans laboratory and clinical strains and to characterize the genetic events involved. A genome-based approach using PFGE coupled with Southern hybridization was employed to examine a total of 58 serotype c oral and blood isolates and seven laboratory strains and to compare them with S. mutans UA159. No significant differences were found in the phenotypic characteristics of the strains tested, except that some of the strains exhibited smooth rather than rough colony morphology. In contrast, PFGE profiles of clinical isolates, from either diseased or healthy subjects, exhibited diverse patterns, suggesting that recombination or point mutations occurred frequently in vivo. Diverse PFGE patterns, with various lengths of insertions and deletions, could be detected even within a localized chromosomal region between rRNA operons. Comparative analysis using Southern hybridization with specific markers revealed that a large chromosomal inversion had also occurred between rrn operons in 25 strains.
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Affiliation(s)
- Wen-Chuan Huang
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | - Yi-Ywan M Chen
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taipei, Taiwan, ROC
| | - Lee-Jene Teng
- Department of Clinical Laboratory Sciences and Medical Biotechnology, Taipei, Taiwan, ROC
| | - Huwei-Ting Lien
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | - Jen-Yang Chen
- National Health Research Institute, Taipei, Taiwan, ROC.,Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | - Jean-San Chia
- Department of Dentistry, National Taiwan University Hospital, Taipei, Taiwan, ROC.,Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC
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Martin JM, Barbadora KA. Continued high caseload of rheumatic fever in western Pennsylvania: Possible rheumatogenic emm types of streptococcus pyogenes. J Pediatr 2006; 149:58-63. [PMID: 16860129 DOI: 10.1016/j.jpeds.2006.03.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2005] [Revised: 01/12/2006] [Accepted: 03/01/2006] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To evaluate the occurrence of cases of acute rheumatic fever (ARF) in western Pennsylvania although there has been a marked reduction of cases of ARF in the United States overall. STUDY DESIGN From 1994 to 2003, the cases of ARF evaluated at Children's Hospital of Pittsburgh were reviewed. In addition, throat cultures were performed on a subset of these children and their family members beginning in 1995. Molecular typing was performed on isolates of the group A streptococcus (GAS) recovered, using field inversion gel electrophoresis (FIGE) and emm typing. RESULTS There were 121 new cases of ARF from 1994 to 2003. Of these, 57% were male. The median age was 10 years. The majority of children (57%) had carditis with or without another manifestation of ARF. The results of throat cultures were available for 231 persons; 36% (30/84) of the children with ARF and 14% (20/147) of family members were positive for GAS. Eight emm types were observed (emm 1, 2, 6, 12, 18, 28, 75, and 89). Data suggest that emm type 12 may be a rheumatogenic strain. CONCLUSION ARF remains a problem in western Pennsylvania. Identification of emm types associated with cases should enlighten vaccine development.
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Affiliation(s)
- Judith Marie Martin
- Department of Pediatrics, Division of Allergy, Immunology and Infectious Diseases, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Farrell DJ, Shackcloth J, Barbadora KA, Green MD. Streptococcus pyogenes isolates with high-level macrolide resistance and reduced susceptibility to telithromycin associated with 23S rRNA mutations. Antimicrob Agents Chemother 2006; 50:817-8. [PMID: 16436755 PMCID: PMC1366915 DOI: 10.1128/aac.50.2.817-818.2006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Seven high-level macrolide-resistant Streptococcus pyogenes isolates had reduced activity to telithromycin but were negative for methylation and efflux genes. All were of the constitutive phenotype, were clonally related (emm type 12 and MLST type 36), and had identical dual mutations (A2058G and U2166C) in domain V of 23S rRNA.
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Affiliation(s)
- David J Farrell
- GR Micro Limited, 7-9 William Road, London, NW1 3ER, United Kingdom.
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Green M, Allen C, Bradley J, Dashefsky B, Gilsdorf JR, Marcon MJ, Schutze GE, Smith C, Walter E, Martin JM, Edwards KA, Barbadora KA, Rumbaugh RM, Wald ER. In vitro activity of telithromycin against macrolide-susceptible and macrolide-resistant pharyngeal isolates of group A streptococci in the United States. Antimicrob Agents Chemother 2005; 49:2487-9. [PMID: 15917551 PMCID: PMC1140514 DOI: 10.1128/aac.49.6.2487-2489.2005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In vitro susceptibility testing of 2,797 group A streptococcus (GAS) isolates demonstrated that telithromycin was fully active against all macrolide-susceptible strains and among 80 of 115 macrolide-resistant GAS expressing the M phenotype. Telithromycin resistance was identified in 2 of 45 strains expressing the inducible macrolide-lincosamide-streptogramin B phenotype and four of nine isolates expressing the constitutive macrolide-lincosamide-streptogramin B resistance phenotype.
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Affiliation(s)
- Michael Green
- Department of Pediatrics, MPH Division of Allergy, Immunology and Infectious Diseases, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, 3705 Fifth Avenue, Pittsburgh, PA 15213, USA.
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Martin JM, Green M, Barbadora KA, Wald ER. Group A streptococci among school-aged children: clinical characteristics and the carrier state. Pediatrics 2004; 114:1212-9. [PMID: 15520098 DOI: 10.1542/peds.2004-0133] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE A 4-year longitudinal study of school-aged children was conducted to describe the clinical characteristics and epidemiologic features of infections with group A streptococci (GAS). METHODS Between 1998 and 2002, surveillance throat cultures were performed twice per month (October to May) for a cohort of elementary school children in Pittsburgh, Pennsylvania. In addition, throat cultures were obtained during any respiratory illness. Erythromycin and clindamycin susceptibility testing was performed for all isolates. Molecular typing was performed with field-inversion gel electrophoresis. Representative isolates from each field-inversion gel electrophoresis group were emm typed. Strict definitions were used to characterize each GAS infection. Children were classified into 4 categories each year, ie, single episode, recurrent episodes, carriers of GAS, and no infections. RESULTS A total of 48 to 100 children per year were studied for 4 years; 61 (49%) were male. The mean age was 9.6 years (range: 5-15 years). A total of 5658 throat cultures were performed; 878 (15.5%) were positive for GAS. Antimicrobial agents were used to treat 209 episodes of infection. Thirteen emm types were observed during the 4-year period. GAS were isolated most often from children who were carriers; isolates from single episodes were next most common. Children carried a single emm type for a mean of 10.8 weeks (range: 3-34 weeks). Carriers were likely to be classified again as carriers in subsequent years and frequently switched emm types. Sixty-two percent of the children had > or =1 year with no infections. CONCLUSIONS GAS infections are common among school-aged children. The majority of positive throat cultures observed in this longitudinal study were obtained from children who were carriers of GAS. Carriers switched emm types but tended to become carriers repeatedly during the study. Practitioners should consider treating children known to be GAS carriers when they develop a new illness that is consistent with streptococcal pharyngitis, because they may acquire new emm types and be at risk for rheumatic heart disease.
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Affiliation(s)
- Judith M Martin
- Department of Pediatrics, Division of Allergy, Immunology, and Infectious Diseases, Children's Hospital of Pittsburgh, 3705 Fifth Ave, Pittsburgh, PA 15213, USA.
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Green M, Martin JM, Barbadora KA, Beall B, Wald ER. Reemergence of macrolide resistance in pharyngeal isolates of group a streptococci in southwestern Pennsylvania. Antimicrob Agents Chemother 2004; 48:473-6. [PMID: 14742197 PMCID: PMC321548 DOI: 10.1128/aac.48.2.473-476.2004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2003] [Revised: 09/24/2003] [Accepted: 10/14/2003] [Indexed: 11/20/2022] Open
Abstract
We previously reported on the emergence of macrolide-resistant pharyngeal isolates of group A streptococci (GAS) in our community. The purpose of the present study was to track longitudinal trends in macrolide resistance in these isolates in southwestern Pennsylvania. Testing for susceptibility to erythromycin and clindamycin was performed for all pharyngeal GAS isolates recovered at the Children's Hospital of Pittsburgh and a local pediatric practice between September 2001 and May 2002. Macrolide resistance phenotypes and genotypes were determined by double-disk diffusion and PCR, respectively. Strain relatedness was determined by field inversion gel electrophoresis and emm gene sequence typing. A total of 708 isolates of GAS were recovered during the study period; 68 (9.6%) were macrolide resistant, while all isolates were sensitive to clindamycin. The monthly prevalence of macrolide resistance ranged from 0 to 41%. Only 21 of 573 (3.7%) strains recovered from September 2001 through March 2002 were macrolide resistant. A sudden increase in the rate of macrolide resistance (47 of 135 isolates [35%]) was seen in April and May 2002. Sixty-two isolates demonstrated the M phenotype (resistance to macrolide antibiotics), and six isolates demonstrated the MLS(B) phenotype (resistance to most macrolide, lincosamide, and streptogramin B antibiotics); these isolates were confirmed to be mef(A) and erm(A), respectively. Three unique mef(A) clones and four unique erm(A) clones were identified among the resistant isolates. The MIC at which 50% of isolates are inhibited (MIC(50)) for the mef(A) strains was 16 micro g/ml, while the MIC(50) for erm(A) strains was 8 micro g/ml. The finding of high levels of macrolide resistance among pharyngeal isolates of GAS for a second successive year in our community raises the concern that this problem may be more common in the United States than was previously appreciated. Longitudinal surveillance of isolates from multiple centers is needed to define the prevalence of antimicrobial agent-resistant GAS in the United States.
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Affiliation(s)
- Michael Green
- Department of Pediatrics, Division of Allergy, Immunology and Infectious Diseases, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
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Yan JJ, Liu CC, Ko WC, Hsu SY, Wu HM, Lin YS, Lin MT, Chuang WJ, Wu JJ. Molecular analysis of group A streptococcal isolates associated with scarlet fever in southern Taiwan between 1993 and 2002. J Clin Microbiol 2004; 41:4858-61. [PMID: 14532243 PMCID: PMC254326 DOI: 10.1128/jcm.41.10.4858-4861.2003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Collected between 1993 and 2002 at a Taiwanese university hospital, 77 group A streptococcus isolates associated with scarlet fever were grouped by emm typing and pulsed-field gel electrophoresis. The predominance of an emm1 clone before 1996 and the presence of genetically diverse emm1 and emm4 strains thereafter were found.
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Affiliation(s)
- Jing-Jou Yan
- Department of Pathology, College of Medicine National Cheng Kung University, Tainan, Taiwan
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10
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Martin JM, Green M, Barbadora KA, Wald ER. Erythromycin-resistant group A streptococci in schoolchildren in Pittsburgh. N Engl J Med 2002; 346:1200-6. [PMID: 11961148 DOI: 10.1056/nejmoa013169] [Citation(s) in RCA: 188] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Resistance to erythromycin has been very uncommon among group A streptococci in the United States. METHODS As part of a longitudinal study, we obtained surveillance throat cultures twice monthly and with each new respiratory tract illness from children in kindergarten through grade 8 at one school in Pittsburgh. Screening for resistance to erythromycin and clindamycin was initially accomplished with use of the Kirby-Bauer disk-diffusion test. The minimal inhibitory concentration of resistant isolates was determined by the E test. A double disk-diffusion test was used to characterize the resistance phenotype, and the polymerase-chain-reaction assay was used to identify the resistance gene. The molecular relatedness of strains was determined by field-inversion gel electrophoresis. RESULTS A total of 1794 throat cultures were obtained from 100 children between October 2000 and May 2001, of which 318 cultures (18 percent) from 60 of the children were positive for group A streptococci. Forty-eight percent of these isolates (153 of 318) were resistant to erythromycin. None were resistant to clindamycin. Results of the double disk-diffusion test indicated the presence of the M phenotype of erythromycin resistance. Molecular typing indicated that the outbreak was due to a single strain of group A streptococci. Of 100 randomly selected isolates of group A streptococci obtained from the community between April and June 2001, 38 were resistant to erythromycin. CONCLUSIONS In January 2001, during a longitudinal study of schoolchildren, we detected the emergence of erythromycin resistance in pharyngeal isolates of group A streptococci. This clonal outbreak also affected the wider community.
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Affiliation(s)
- Judith M Martin
- Department of Pediatrics, Division of Allergy, Immunology and Infectious Diseases, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh 15213, USA.
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Frumin LL, Peltek SE, Zilberstein GV. Rapid separation of large DNA fragments. Anal Biochem 2001; 293:288-91. [PMID: 11399045 DOI: 10.1006/abio.2001.5123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- L L Frumin
- Proteologics (Israel) Ltd., Weizmann Science Park, 5 Oppenhaimer Street, Rehovot, 76701, Israel
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Frumin LL, Peltek SE, Zilberstein GV. Nonlinear electrophoresis and focusing of macromolecules. JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS 2001; 48:269-82. [PMID: 11384763 DOI: 10.1016/s0165-022x(01)00161-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Effects of nonlinear dependence drift velocity of (double-stranded) DNA vs. electric field strength were investigated. In comparatively weak fields, the molecular drift velocity is proportional to the external electric field, while in strong fields there is additional nonlinear component. This effect offers possibilities to manipulate the total drift velocity at will-the macromolecules of different size can be made to move in opposite directions in pulsed field gel electrophoresis.A new approach for focusing DNA molecules based on nonlinear electrophoresis and geometric trapping in electric fields is proposed. The focusing is carried out in an alternating nonuniform electric field, created by using a wedge gel with hyperbolic boundaries. It is shown that the fractions separated in such wedge retain their rectilinear shape. Gel electrophoresis experiments supported the possibility of a pronounced nonlinear focusing of DNA molecules. This nonlinear separation technique presents encouraging prospects for micromanipulating systems and also for preparative isolation of long DNA fragments and development of new separation methods for bacterial fingerprinting.
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Affiliation(s)
- L L Frumin
- Proteologics (Israel) Ltd., Weizmann Science Park, Bld. Lev HaPark, Str. Oppenhaimer 5, 76701, Rehovot, Israel
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Busch U, Nitschko H. Methods for the differentiation of microorganisms. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1999; 722:263-78. [PMID: 10068145 DOI: 10.1016/s0378-4347(98)00369-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Advances in analytical and diagnostic assays based on novel nucleic acid analyses techniques have revolutionized the application of molecular differentiation of microorganisms. Phenotypic typing schemes are now broadly supplemented by new genotyping methods which allow a more refined and detailed differentiation of closely related microorganisms, bacterial strains, isolates and pathogens on the DNA level. Bio-, sero- and phagetyping, antibiotic susceptibility tests, immunoblotting as well as multilocus enzyme- or polyacrylamide gel electrophoresis are now supported by the analysis of plasmid or chromosomal DNA restriction profiles, ribotyping, pulsed-field gel electrophoresis and polymerase- or ligase-chain reaction-based methods or direct sequencing technique to differentiate microorganisms. Some of these molecular techniques are also used in the field of virology to analyse and differentiate closely related sub- or genotypes. Few examples for the analysis and investigation of these usually small genomes will also be given.
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Affiliation(s)
- U Busch
- Landesuntersuchungsamt für das Gesundheitswesen Südbayern, Oberschleissheim, Germany
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