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Hellenbrand W, Elias J, Wichmann O, Dehnert M, Frosch M, Vogel U. Epidemiology of invasive meningococcal disease in Germany, 2002-2010, and impact of vaccination with meningococcal C conjugate vaccine. J Infect 2012; 66:48-56. [PMID: 23043893 DOI: 10.1016/j.jinf.2012.09.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 09/04/2012] [Accepted: 09/11/2012] [Indexed: 11/19/2022]
Abstract
OBJECTIVES To analyse serogroup (Sg)- and finetype-specific invasive meningococcal disease burden (IMD) in Germany, 2002-2010, with emphasis on effects of vaccination with conjugate SgC vaccines targeting one-year old children since 2006, including individual-based catch-up to 17 years of age. METHODS Serogroup- and age-specific IMD incidence and trends were calculated using statutory surveillance data. The national reference laboratory performed genetic finetyping. Vaccination uptake data were obtained from school entry surveys and prescription monitoring. RESULTS In persons <25 years, SgB and SgC IMD incidence decreased significantly from 0.63 to 0.32/100,000 and 0.26 to 0.10/100,000, respectively. The decline was significantly steeper for SgC than SgB in 1-5 year-olds, the primary vaccination target group, but not other ages. The slope of the SgC incidence curves was similar before and after vaccination implementation in all age groups; however, the decrease in incidence was steeper in states with higher vaccination uptake. Declining SgC incidence was associated with decreased SgC finetype diversity. An increase in SgY incidence was limited to adults. CONCLUSIONS Results suggest effects of the German SgC vaccination strategy are limited, although interpretation is complicated by already low and decreasing incidence before vaccination. More effective use of vaccination resources might be achieved by rigorously targeting adolescents in addition to 1-year-olds.
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Affiliation(s)
- Wiebke Hellenbrand
- Immunization Unit, Department of Infectious Disease Epidemiology, Robert Koch Institute, Berlin, Germany.
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Abstract
The human bacterial pathogen Neisseria meningitidis remains a serious worldwide health threat, but progress is being made toward the control of meningococcal infections. This review summarizes current knowledge of the global epidemiology and the pathophysiology of meningococcal disease, as well as recent advances in prevention by new vaccines. Meningococcal disease patterns and incidence can vary dramatically, both geographically and over time in populations, influenced by differences in invasive meningococcal capsular serogroups and specific genotypes designated as ST clonal complexes. Serogroup A (ST-5, ST-7), B (ST-41/44, ST-32, ST-18, ST-269, ST-8, ST-35), C (ST-11), Y (ST-23, ST-167), W-135 (ST-11) and X (ST-181) meningococci currently cause almost all invasive disease. Serogroups B, C, and Y are responsible for the majority of cases in Europe, the Americas, and Oceania; serogroup A has been associated with the highest incidence (up to 1000 per 100,000 cases) and large outbreaks of meningococcal disease in sub-Saharan Africa and previously Asia; and serogroups W-135 and X have emerged to cause major disease outbreaks in sub-Saharan Africa. Significant declines in meningococcal disease have occurred in the last decade in many developed countries. In part, the decline is related to the introduction of new meningococcal vaccines. Serogroup C polysaccharide-protein conjugate vaccines were introduced over a decade ago, first in the UK in a mass vaccination campaign, and are now widely used; multivalent meningococcal conjugate vaccines containing serogroups A, C, W-135, and/or Y were first used for adolescents in the US in 2005 and have now expanded indications for infants and young children, and a new serogroup A conjugate vaccine has recently been introduced in sub-Saharan Africa. The effectiveness of these conjugate vaccines has been enhanced by the prevention of person-to-person transmission and herd immunity. In addition, progress has been made in serogroup B-specific vaccines based on conserved proteins and outer membrane vesicles. However, continued global surveillance is essential in understanding and predicting the dynamic changes in the epidemiology and biological basis of meningococcal disease and to influence the recommendations for current and future vaccines or other prevention strategies.
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Affiliation(s)
- Qiuzhi Chang
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA
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Vogel U, Stefanelli P, Vazquez J, Taha MK, Claus H, Donnelly J. The use of vaccine antigen characterization, for example by MATS, to guide the introduction of meningococcus B vaccines. Vaccine 2012; 30 Suppl 2:B73-7. [PMID: 22607902 DOI: 10.1016/j.vaccine.2011.12.061] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Revised: 12/12/2011] [Accepted: 12/13/2011] [Indexed: 10/28/2022]
Abstract
Current concepts of vaccines against serogroup B meningococci (MenB) are mainly based on genetically variable protein antigens. Vaccine efficacy studies for meningococcal disease in developed countries are hampered by the low incidence. Licensure must therefore exclusively rely on clinical trials and laboratory investigation of meningococcal strains. In contrast to capsule polysaccharide vaccines, serum bactericidal assays for technical reasons are limited in their practicability as the surrogate of protection provided by MenB vaccines. Therefore, assays are required for reliable laboratory based assessment of expression of those specific antigen variants that are predicted to be targeted by bactericidal antibodies elicited by the vaccine. The MATS ELISA (MATS, meningococcal antigen typing system) reported recently is an example for such an assay. The paper discusses the pre- and post-licensure application of MATS, the role of reference laboratories, concepts of sustained provision of the assay, external quality assessment, and laboratory twinning.
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Affiliation(s)
- Ulrich Vogel
- Institute for Hygiene and Microbiology, National Reference Laboratory for Meningococci, University of Würzburg, Germany.
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Clonal analysis of Neisseria meningitidis serogroup B strains in South Africa, 2002 to 2006: emergence of new clone ST-4240/6688. J Clin Microbiol 2012; 50:3678-86. [PMID: 22972827 DOI: 10.1128/jcm.01079-12] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
From August 1999 through July 2002, hyperinvasive Neisseria meningitidis serogroup B (MenB) clonal complexes (CCs), namely, ST-32/ET-5 (CC32) and ST-41/44/lineage 3 (CC41/44), were predominant in the Western Cape Province of South Africa. This study analyzed MenB invasive isolates from a national laboratory-based surveillance system that were collected from January 2002 through December 2006. Isolates were characterized by pulsed-field gel electrophoresis (PFGE) (n = 302), and multilocus sequence typing (MLST) and PorA and FetA typing were performed on randomly selected isolates (34/302, 11%). In total, 2,400 cases were reported, with the highest numbers from Gauteng Province (1,307/2,400, 54%) and Western Cape Province (393/2,400, 16%); 67% (1,617/2,400) had viable isolates and 19% (307/1,617) were identified as serogroup B. MenB incidence remained stable over time (P = 0.77) (average incidence, 0.13/100,000 population [range, 0.10 to 0.16/100,000 population]). PFGE (302/307, 98%) divided isolates (206/302, 68%) into 13 clusters and 96 outliers. The largest cluster, B1, accounted for 25% of isolates (76/302) over the study period; its prevalence decreased from 43% (20/47) in 2002 to 13% (8/62) in 2006 (P < 0.001), and it was common in the Western Cape (58/76, 76%). Clusters B2 and B3 accounted for 10% (31/302) and 6% (19/302), respectively, and showed no significant change over time and were predominant in Gauteng. Randomly selected isolates from clusters B1, B2, and B3 belonged to CC32, CC41/44, and the new CC4240/6688, respectively. Overall, 15 PorA and 12 FetA types were identified. MenB isolates were mostly diverse with no single dominant clone; however, CC32 and CC41/44 accounted for 35% and the new CC4240/6688 was the third most prevalent clone.
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Interlaboratory standardization of the sandwich enzyme-linked immunosorbent assay designed for MATS, a rapid, reproducible method for estimating the strain coverage of investigational vaccines. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2012; 19:1609-17. [PMID: 22875603 DOI: 10.1128/cvi.00202-12] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The meningococcal antigen typing system (MATS) sandwich enzyme-linked immunosorbent assay (ELISA) was designed to measure the immunologic cross-reactivity and quantity of antigens in target strains of a pathogen. It was first used to measure the factor H-binding protein (fHbp), neisserial adhesin A (NadA), and neisserial heparin-binding antigen (NHBA) content of serogroup B meningococcal (MenB) isolates relative to a reference strain, or "relative potency" (RP). With the PorA genotype, the RPs were then used to assess strain coverage by 4CMenB, a multicomponent MenB vaccine. In preliminary studies, MATS accurately predicted killing in the serum bactericidal assay using human complement, an accepted correlate of protection for meningococcal vaccines. A study across seven laboratories assessed the reproducibility of RPs for fHbp, NadA, and NHBA and established qualification parameters for new laboratories. RPs were determined in replicate for 17 MenB reference strains at laboratories A to G. The reproducibility of RPs among laboratories and against consensus values across laboratories was evaluated using a mixed-model analysis of variance. Interlaboratory agreement was very good; the Pearson correlation coefficients, coefficients of accuracy, and concordance correlation coefficients exceeded 99%. The summary measures of reproducibility, expressed as between-laboratory coefficients of variation, were 7.85% (fHbp), 16.51% (NadA), and 12.60% (NHBA). The overall within-laboratory measures of variation adjusted for strain and laboratory were 19.8% (fHbp), 28.8% (NHBA), and 38.3% (NadA). The MATS ELISA was successfully transferred to six laboratories, and a further laboratory was successfully qualified.
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Adamiak P, Beddek AJ, Pajon R, Schryvers AB. Patterns of sequence variation within the Neisseria meningitidis lactoferrin binding proteins1This article is part of a Special Issue entitled Lactoferrin and has undergone the Journal’s usual peer review process. Biochem Cell Biol 2012; 90:339-50. [DOI: 10.1139/o11-076] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lactoferrin binding proteins A and B (LbpA and LbpB) compose the lactoferrin receptor of the obligate human pathogen Neisseria meningitidis . This receptor is thought to be important for colonization and initiation of invasive disease because of its role in acquiring host iron and providing protection from the cationic peptide, lactoferricin. By virtue of its function, the receptor is accessible to the host immune system and displays substantial sequence variation. In this study, we analyzed a broad collection of LbpAs (62) and LbpBs (101) to determine the distribution of sequence variation within each protein and to search for patterns between sequence similarity and strain typing. The sequence variation in LbpA was predominantly observed in 3 surface loops and, surprisingly, in the N-terminal region immediately upstream of the predicted TonB box. The analysis of LbpB revealed that the variability was distributed throughout the protein, particularly in the highly variable negatively charged regions in the C-lobe, but otherwise was greater in the N-lobe than the C-lobe. There was no readily identifiable correlation between the sequence variation within LbpA, LbpB, multi-locus sequence type, or serogroup.
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Affiliation(s)
- Paul Adamiak
- Department of Microbiology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
| | - Amanda J. Beddek
- Department of Microbiology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
| | - Rolando Pajon
- Department of Microbiology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
| | - Anthony B. Schryvers
- Department of Microbiology and Infectious Diseases, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
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de Filippis I, de Lemos APS, Hostetler JB, Wollenberg K, Sacchi CT, Harrison LH, Bash MC, Prevots DR. Molecular epidemiology of Neisseria meningitidis serogroup B in Brazil. PLoS One 2012; 7:e33016. [PMID: 22431994 PMCID: PMC3303791 DOI: 10.1371/journal.pone.0033016] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 02/03/2012] [Indexed: 11/23/2022] Open
Abstract
Background Neisseria meningitidis serogroup B has been predominant in Brazil, but no broadly effective vaccine is available to prevent endemic meningococcal disease. To understand genetic diversity among serogroup B strains in Brazil, we selected a nationally representative sample of clinical disease isolates from 2004, and a temporally representative sample for the state of São Paulo (1988–2006) for study (n = 372). Methods We performed multi-locus sequence typing (MLST) and sequence analysis of five outer membrane protein (OMP) genes, including novel vaccine targets fHbp and nadA. Results In 2004, strain B:4:P1.15,19 clonal complex ST-32/ET-5 (cc32) predominated throughout Brazil; regional variation in MLST sequence type (ST), fetA, and porB was significant but diversity was limited for nadA and fHbp. Between 1988 and 1996, the São Paulo isolates shifted from clonal complex ST-41/44/Lineage 3 (cc41/44) to cc32. OMP variation was associated with but not predicted by cc or ST. Overall, fHbp variant 1/subfamily B was present in 80% of isolates and showed little diversity. The majority of nadA were similar to reference allele 1. Conclusions A predominant serogroup B lineage has circulated in Brazil for over a decade with significant regional and temporal diversity in ST, fetA, and porB, but not in nadA and fHbp.
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Affiliation(s)
- Ivano de Filippis
- National Quality Control Institute (INCQS), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research (CBER), Food and Drug Administration (FDA), Bethesda, Maryland, United States of America
- Epidemiology Unit, Laboratory of Clinical Infectious Diseases, Division of Intramural Research, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | | | | | - Kurt Wollenberg
- Office of Cyberinfrastructure and Computational Biology (OCICB), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | | | - Lee H. Harrison
- Infectious Diseases Epidemiology Research Unit, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Margaret C. Bash
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research (CBER), Food and Drug Administration (FDA), Bethesda, Maryland, United States of America
| | - D. Rebecca Prevots
- Epidemiology Unit, Laboratory of Clinical Infectious Diseases, Division of Intramural Research, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, Maryland, United States of America
- * E-mail:
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Genotypic and phenotypic characterization of carriage and invasive disease isolates of Neisseria meningitidis in Finland. J Clin Microbiol 2011; 50:264-73. [PMID: 22135261 DOI: 10.1128/jcm.05385-11] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The relationship between carriage and the development of invasive meningococcal disease is not fully understood. We investigated the changes in meningococcal carriage in 892 military recruits in Finland during a nonepidemic period (July 2004 to January 2006) and characterized all of the oropharyngeal meningococcal isolates obtained (n = 215) by using phenotypic (serogrouping and serotyping) and genotypic (porA typing and multilocus sequence typing) methods. For comparison, 84 invasive meningococcal disease strains isolated in Finland between January 2004 and February 2006 were also analyzed. The rate of meningococcal carriage was significantly higher at the end of military service than on arrival (18% versus 2.2%; P < 0.001). Seventy-four percent of serogroupable carriage isolates belonged to serogroup B, and 24% belonged to serogroup Y. Most carriage isolates belonged to the carriage-associated ST-60 clonal complex. However, 21.5% belonged to the hyperinvasive ST-41/44 clonal complex. Isolates belonging to the ST-23 clonal complex were cultured more often from oropharyngeal samples taken during the acute phase of respiratory infection than from samples taken at health examinations at the beginning and end of military service (odds ratio [OR], 6.7; 95% confidence interval [95% CI], 2.7 to 16.4). The ST-32 clonal complex was associated with meningococcal disease (OR, 17.8; 95% CI, 3.8 to 81.2), while the ST-60 clonal complex was associated with carriage (OR, 10.7; 95% CI, 3.3 to 35.2). These findings point to the importance of meningococcal vaccination for military recruits and also to the need for an efficacious vaccine against serogroup B isolates.
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Ibarz-Pavón AB, MacLennan J, Andrews NJ, Gray SJ, Urwin R, Clarke SC, Walker AM, Evans MR, Kroll JS, Neal KR, Ala'Aldeen D, Crook DW, Cann K, Harrison S, Cunningham R, Baxter D, Kaczmarski E, McCarthy ND, Jolley KA, Cameron JC, Stuart JM, Maiden MCJ. Changes in serogroup and genotype prevalence among carried meningococci in the United Kingdom during vaccine implementation. J Infect Dis 2011; 204:1046-53. [PMID: 21881120 PMCID: PMC3164428 DOI: 10.1093/infdis/jir466] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 05/13/2011] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Herd immunity is important in the effectiveness of conjugate polysaccharide vaccines against encapsulated bacteria. A large multicenter study investigated the effect of meningococcal serogroup C conjugate vaccine introduction on the meningococcal population. METHODS Carried meningococci in individuals aged 15-19 years attending education establishments were investigated before and for 2 years after vaccine introduction. Isolates were characterized by multilocus sequence typing, serogroup, and capsular region genotype and changes in phenotypes and genotypes assessed. RESULTS A total of 8462 meningococci were isolated from 47 765 participants (17.7%). Serogroup prevalence was similar over the 3 years, except for decreases of 80% for serogroup C and 40% for serogroup 29E. Clonal complexes were associated with particular serogroups and their relative proportions fluctuated, with 12 statistically significant changes (6 up, 6 down). The reduction of ST-11 complex serogroup C meningococci was probably due to vaccine introduction. Reasons for a decrease in serogroup 29E ST-254 meningococci (from 1.8% to 0.7%) and an increase in serogroup B ST-213 complex meningococci (from 6.7% to 10.6%) were less clear. CONCLUSIONS Natural fluctuations in carried meningococcal genotypes and phenotypes a can be affected by the use of conjugate vaccines, and not all of these changes are anticipatable in advance of vaccine introduction.
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Affiliation(s)
| | | | | | - Stephen J. Gray
- Meningococcal Reference Unit, Health Protection Agency, Manchester Medical Microbiology Partnership, Manchester Royal Infirmary
| | | | - Stuart C. Clarke
- Division of Infection, Inflammation and Immunity, University of Southampton, School of Medicine, Southampton National Institute for Health Research Biomedical Research Unit in Respiratory Medicine, and Health Protection Agency, Southampton
| | | | - Meirion R. Evans
- Department of Primary Care and Public Health, Cardiff University
| | - J. Simon Kroll
- Imperial College School of Medicine, Norfolk Place, London
| | - Keith R. Neal
- University of Nottingham, Epidemiology and Public Health, Community Health Sciences, Queen's Medical Centre
| | - Dlawer Ala'Aldeen
- Division of Microbiology, School of Molecular Medicine, University Hospital, Nottingham
| | - Derrick W. Crook
- Nuffield Department of Clinical and Laboratory Sciences, John Radcliffe Hospital, Headley Way, University of Oxford
| | - Kathryn Cann
- Nuffield Department of Clinical and Laboratory Sciences, John Radcliffe Hospital, Headley Way, University of Oxford
| | | | | | - David Baxter
- Division of Epidemiology and Health Sciences, Medical School, The University of Manchester
| | - Edward Kaczmarski
- Meningococcal Reference Unit, Health Protection Agency, Manchester Medical Microbiology Partnership, Manchester Royal Infirmary
| | | | | | | | - James M. Stuart
- School of Social and Community Medicine, University of Bristol, United Kingdom
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Harrison OB, Brueggemann AB, Caugant DA, van der Ende A, Frosch M, Gray S, Heuberger S, Krizova P, Olcen P, Slack M, Taha MK, Maiden MCJ. Molecular typing methods for outbreak detection and surveillance of invasive disease caused by Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae, a review. MICROBIOLOGY (READING, ENGLAND) 2011; 157:2181-2195. [PMID: 21622526 PMCID: PMC3980633 DOI: 10.1099/mic.0.050518-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Invasive disease caused by the encapsulated bacteria Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae remains an important cause of morbidity and mortality worldwide, despite the introduction of successful conjugate polysaccharide vaccines that target disease-associated strains. In addition, resistance, or more accurately reduced susceptibility, to therapeutic antibiotics is spreading in populations of these organisms. There is therefore a continuing requirement for the surveillance of vaccine and non-vaccine antigens and antibiotic susceptibilities among isolates from invasive disease, which is only partially met by conventional methods. This need can be met with molecular and especially nucleotide sequence-based typing methods, which are fully developed in the case of N. meningitidis and which could be more widely deployed in clinical laboratories for S. pneumoniae and H. influenzae.
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Affiliation(s)
- Odile B. Harrison
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK
| | | | - Dominique A. Caugant
- Department of Bacteriology and Immunology, Norwegian Institute of Public Health, PO Box 4404 Nydalen, NO-0403 Oslo, Norway
| | - Arie van der Ende
- Academic Medical Center, Department of Medical Microbiology, Reference Laboratory for Bacterial Meningitis, PO Box 22660, 1100 DD Amsterdam, The Netherlands
| | - Matthias Frosch
- Institut für Hygiene und Mikrobiologie, Universität Würzburg, Josef-Schneider Strasse 2, 97080 Würzburg, Germany
| | - Stephen Gray
- Meningococcal Reference Unit, Health Protection Agency, PO Box 209, Clinical Sciences Building 2, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
| | - Sigrid Heuberger
- Österreichische Agentur für Gesundheit und Ernährungssicherheit GmbH, Bereich Humanmedizin, Institut für medizinische Mikrobiologie und Hygiene, Beethovenstraße 6, A-8010 Graz, Austria
| | - Paula Krizova
- National Reference Laboratory for Meningococcal Infections, National Institute of Public Health, Srobarova 48, Prague, Czech Republic
| | - Per Olcen
- Department of Laboratory Medicine, Clinical Microbiology and Immunology, Orebro University Hospital, SE-701 85 Orebro, Sweden
| | - Mary Slack
- Respiratory and Systemic Infection Laboratory, Health Protection Agency Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, UK
| | | | - Martin C. J Maiden
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK
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Joseph B, Schwarz RF, Linke B, Blom J, Becker A, Claus H, Goesmann A, Frosch M, Müller T, Vogel U, Schoen C. Virulence evolution of the human pathogen Neisseria meningitidis by recombination in the core and accessory genome. PLoS One 2011; 6:e18441. [PMID: 21541312 PMCID: PMC3082526 DOI: 10.1371/journal.pone.0018441] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 02/28/2011] [Indexed: 11/18/2022] Open
Abstract
Background Neisseria meningitidis is a naturally transformable, facultative pathogen colonizing the human nasopharynx. Here, we analyze on a genome-wide level the impact of recombination on gene-complement diversity and virulence evolution in N. meningitidis. We combined comparative genome hybridization using microarrays (mCGH) and multilocus sequence typing (MLST) of 29 meningococcal isolates with computational comparison of a subset of seven meningococcal genome sequences. Principal Findings We found that lateral gene transfer of minimal mobile elements as well as prophages are major forces shaping meningococcal population structure. Extensive gene content comparison revealed novel associations of virulence with genetic elements besides the recently discovered meningococcal disease associated (MDA) island. In particular, we identified an association of virulence with a recently described canonical genomic island termed IHT-E and a differential distribution of genes encoding RTX toxin- and two-partner secretion systems among hyperinvasive and non-hyperinvasive lineages. By computationally screening also the core genome for signs of recombination, we provided evidence that about 40% of the meningococcal core genes are affected by recombination primarily within metabolic genes as well as genes involved in DNA replication and repair. By comparison with the results of previous mCGH studies, our data indicated that genetic structuring as revealed by mCGH is stable over time and highly similar for isolates from different geographic origins. Conclusions Recombination comprising lateral transfer of entire genes as well as homologous intragenic recombination has a profound impact on meningococcal population structure and genome composition. Our data support the hypothesis that meningococcal virulence is polygenic in nature and that differences in metabolism might contribute to virulence.
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Affiliation(s)
- Biju Joseph
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Roland F. Schwarz
- Cancer Research UK Cambridge Research Institute, Li Ka Shing Centre, Cambridge, United Kingdom
| | - Burkhard Linke
- Center for Biotechnology, Bielefeld University, Bielefeld, Germany
| | - Jochen Blom
- Center for Biotechnology, Bielefeld University, Bielefeld, Germany
| | - Anke Becker
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Heike Claus
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
- National Reference Laboratory for Meningococci (NRZM), Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | | | - Matthias Frosch
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
- National Reference Laboratory for Meningococci (NRZM), Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Tobias Müller
- Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Ulrich Vogel
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
- National Reference Laboratory for Meningococci (NRZM), Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Christoph Schoen
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
- * E-mail:
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Bertrand S, Van Meervenne E, De Baere T, Vanhoof R, Collard JM, Ruckly C, Taha M, Carion F. Detection of a geographical and endemic cluster of hyper-invasive meningococcal strains. Microbes Infect 2011; 13:684-90. [PMID: 21376133 DOI: 10.1016/j.micinf.2011.02.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Revised: 02/01/2011] [Accepted: 02/17/2011] [Indexed: 01/10/2023]
Abstract
From 2006 to December 2009, 45 out of the 513 strains isolated from patients with invasive meningococcal disease in Belgium, were identified as Neisseria meningitidis serogroup B, non-serotypeable, subtype P1.14 (B:NT:P1.14). Most cases were geographically clustered in the northern part of the country. Multilocus Sequence Typing and antigen gene sequencing combined with Pulsed-Field Gel electrophoresis were used to investigate this cluster. Molecular typing showed that 39 out of these 45 N. meningitidis strains belonged to the clonal complex cc-269. The presence of the same PorA Variable Regions (VR1-VR2: 22, 14), the FetA allele (F5-1) and the highly similar Pulsed-Field Gel Electrophoresis profiles, supported genetic relatedness for 38 out of these 39 isolates. Retrospective analysis of B:NT:P1.22,14 isolates from 1999 onwards suggested that these strains belonging to the cc-269 complex, first emerged in the Belgian province of West-Flanders in 2004. This study showed that the combination of molecular tools with classical methods enabled reliable outbreak detection as well as a cluster identification.
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Affiliation(s)
- Sophie Bertrand
- National Reference Centre for Neisseria meningitidis, Bacterial Diseases Division, Communicable and Infectious Diseases, Scientific Institute of Public Health, J. Wytsman Street, 14-16, B-1050 Brussels, Belgium.
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Lucidarme J, Newbold LS, Findlow J, Gilchrist S, Gray SJ, Carr AD, Hewitt J, Kaczmarski EB, Borrow R. Molecular targets in meningococci: efficient routine characterization and optimal outbreak investigation in conjunction with routine surveillance of the meningococcal group B vaccine candidate, fHBP. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2011; 18:194-202. [PMID: 21123522 PMCID: PMC3067353 DOI: 10.1128/cvi.00401-10] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 10/25/2010] [Accepted: 11/22/2010] [Indexed: 11/20/2022]
Abstract
In 2007, recommendations were proposed for the molecular typing of meningococci. Multilocus sequence typing (MLST) was recommended to guide national and international disease management and facilitate studies of population biology and evolution. Sequencing of porA variable regions (VRs) 1 and 2 and the fetA VR was recommended for monitoring antigenic distribution and investigating potential outbreaks. porB characterization was recommended if further resolution was required. Several investigational "group B" meningococcal vaccines, including two in the advanced stages of development, incorporate factor H-binding protein (fHBP). The requirement for routine surveillance of fhbp places additional pressure on reference laboratories, both financially and in terms of labor. This study investigated the optimal and most efficient molecular typing schemes for (i) routine meningococcal characterization and (ii) the investigation of potential outbreaks, in conjunction with routine surveillance of fhbp. All invasive disease isolates received by the Health Protection Agency Meningococcal Reference Unit between July 2007 and June 2008 (n = 613) were characterized in terms of capsular group, porA, fetA VR, fhbp, and sequence type (ST). Following capsular grouping and porA genosubtyping, several predominant capsular group-porA combinations were identified. The levels of additional resolution afforded by fetA and fhbp were comparable and partially complementary. fhbp constitutes an effective substitute for fetA as a routine marker of antigenic distribution, thereby reducing costs in conjunction with fhbp surveillance. MLST afforded markedly superior resolution overall and is the optimal scheme for investigating outbreaks in which (i) typing data are unavailable for the index case or (ii) the index case possesses a known, predominant capsular group-porA repertoire.
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Affiliation(s)
- Jay Lucidarme
- Vaccine Evaluation Unit, Health Protection Agency, PO Box 209, Floor 2, Clinical Sciences Building 2, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, United Kingdom.
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64
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False-negative PCR result due to gene polymorphism: the example of Neisseria meningitidis. J Clin Microbiol 2010; 48:4590-1. [PMID: 20962143 DOI: 10.1128/jcm.01766-10] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Early treatment of meningococcal meningitis is mandatory but may negate the cerebrospinal fluid culture. Etiological diagnosis then mainly relies on PCR. Here, we report a case of false-negative results for real-time PCR for a Neisseria meningitidis serogroup B isolate with a polymorphism in the ctrA gene.
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65
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Elias J, Schouls LM, van de Pol I, Keijzers WC, Martin DR, Glennie A, Oster P, Frosch M, Vogel U, van der Ende A. Vaccine preventability of meningococcal clone, Greater Aachen Region, Germany. Emerg Infect Dis 2010; 16:465-72. [PMID: 20202422 PMCID: PMC3322024 DOI: 10.3201/eid1603.091102] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
An emerging serogroup B clone can be prevented by vaccines. Emergence of serogroup B meningococci of clonal complex sequence type (ST) 41/44 can cause high levels of disease, as exemplified by a recent epidemic in New Zealand. Multiplication of annual incidence rates (3.1 cases/100,000 population) of meningococcal disease in a defined German region, the city of Aachen and 3 neighboring countries (Greater Aachen) prompted us to investigate and determine the source and nature of this outbreak. Using molecular typing and geographic mapping, we analyzed 1,143 strains belonging to ST41/44 complex, isolated from persons with invasive meningococcal disease over 6 years (2001–2006) from 2 German federal states (total population 26 million) and the Netherlands. A spatially slowly moving clone with multiple-locus variable-number tandem repeat analysis type 19, ST42, and antigenic profile B:P1.7–2,4:F1–5 was responsible for the outbreak. Bactericidal activity in serum samples from the New Zealand MeNZB vaccination campaign confirmed vaccine preventability. Because this globally distributed epidemic strain spreads slowly, vaccination efforts could possibly eliminate meningococcal disease in this area.
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66
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Molecular epidemiology of meningococci: application of DNA sequence typing. Int J Med Microbiol 2010; 300:415-20. [PMID: 20537945 DOI: 10.1016/j.ijmm.2010.04.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2009] [Revised: 04/08/2010] [Accepted: 04/19/2010] [Indexed: 11/22/2022] Open
Abstract
Neisseria meningitidis is an invasive pathogen contributing significantly to childhood mortality worldwide. The organism is adapted to the human host and transmitted by close contact or droplet aerosols. In comparison to healthy carriage, invasive disease is a rare event. Nevertheless, due to a high case-fatality rate and the fact that meningococcal infection is a communicable disease, molecular typing of meningococci has been driven forward considerably in the past decades. Multilocus and antigen sequence typing data are assembled in large databases accessible via the internet. For epidemiological purposes, representative case ascertainment strategies are necessary if data are to be exploited for trend analysis, geographic visualization, detection of abnormalities such as outbreaks, and prediction of vaccine coverage. In Europe, a consensus for molecular typing has been achieved.
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67
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Giuliani MM, Biolchi A, Serruto D, Ferlicca F, Vienken K, Oster P, Rappuoli R, Pizza M, Donnelly J. Measuring antigen-specific bactericidal responses to a multicomponent vaccine against serogroup B meningococcus. Vaccine 2010; 28:5023-30. [PMID: 20493284 DOI: 10.1016/j.vaccine.2010.05.014] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Revised: 05/03/2010] [Accepted: 05/05/2010] [Indexed: 10/19/2022]
Abstract
Serum bactericidal activity using human complement is the basis for established correlates of protection against invasive meningococcal disease. During the development of multicomponent protein-based vaccines against meningococcus B, it is necessary to measure antigen-specific bactericidal responses. This is not straightforward because each strain may be killed by antibodies to multiple antigens. We characterized a large panel of strains and, using a competitive inhibition SBA, we identified four strains that are each specifically killed by bactericidal antibodies to one of the major vaccine components. These strains provide a straightforward approach to demonstrate protective responses to each component of the vaccine and demonstrate that each of the antigens in the vaccine is sufficient to provide a potentially protective level of bactericidal activity.
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Affiliation(s)
- Marzia M Giuliani
- Novartis Vaccines and Diagnostics, Via Fiorentina 1, Siena 53100, Italy
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68
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Biofilm formation by the human pathogen Neisseria meningitidis. Med Microbiol Immunol 2010; 199:173-83. [PMID: 20376486 DOI: 10.1007/s00430-010-0149-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Indexed: 10/19/2022]
Abstract
The past decade has seen an increasing interest in biofilm formation by Neisseria meningitidis, a human facultative pathogen causing life-threatening childhood disease commencing from asymptomatic nasopharyngeal colonization. Studying the biology of in vitro biofilm formation improves the understanding of inter-bacterial processes in asymptomatic carriage, of bacterial aggregate formation on host cells, and of meningococcal population biology. This paper reviews publications referring to meningococcal biofilm formation with an emphasis on the role of motility and of extracellular DNA. The theory of sub-dividing the meningococcal population in settler and spreader lineages is discussed, which provides a mechanistic framework for the assumed balance of colonization efficacy and transmission frequency.
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69
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Almeida NF, Yan S, Cai R, Clarke CR, Morris CE, Schaad NW, Schuenzel EL, Lacy GH, Sun X, Jones JB, Castillo JA, Bull CT, Leman S, Guttman DS, Setubal JC, Vinatzer BA. PAMDB, a multilocus sequence typing and analysis database and website for plant-associated microbes. PHYTOPATHOLOGY 2010; 100:208-15. [PMID: 20128693 DOI: 10.1094/phyto-100-3-0208] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Although there are adequate DNA sequence differences among plant-associated and plant-pathogenic bacteria to facilitate molecular approaches for their identification, identification at a taxonomic level that is predictive of their phenotype is a challenge. The problem is the absence of a taxonomy that describes genetic variation at a biologically relevant resolution and of a database containing reference strains for comparison. Moreover, molecular evolution, population genetics, ecology, and epidemiology of many plant-pathogenic and plant-associated bacteria are still poorly understood. To address these challenges, a database with web interface was specifically designed for plant-associated and plant-pathogenic microorganisms. The Plant-Associated Microbes Database (PAMDB) comprises, thus far, data from multilocus sequence typing and analysis (MLST/MLSA) studies of Acidovorax citrulli, Pseudomonas syringae, Ralstonia solanacearum, and Xanthomonas spp. Using data deposited in PAMDB, a robust phylogeny of Xanthomonas axonopodis and related bacteria has been inferred, and the diversity existing in the Xanthomonas genus and in described Xanthomonas spp. has been compared with the diversity in P. syringae and R. solanacearum. Moreover, we show how PAMDB makes it easy to distinguish between different pathogens that cause almost identical diseases. The scalable design of PAMDB will make it easy to add more plant pathogens in the future.
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Affiliation(s)
- Nalvo F Almeida
- Department of Plant Pahtology, Physiology, and Weed Science, Virginia Tech, Blacksburg, 24061, USA
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70
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Lappann M, Claus H, van Alen T, Harmsen M, Elias J, Molin S, Vogel U. A dual role of extracellular DNA during biofilm formation ofNeisseria meningitidis. Mol Microbiol 2010; 75:1355-71. [DOI: 10.1111/j.1365-2958.2010.07054.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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71
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Abstract
The human species is the only natural host of Neisseria meningitidis, an important cause of bacterial meningitis globally, and, despite its association with devastating diseases, N. meningitidis is a commensal organism found frequently in the respiratory tract of healthy individuals. To date, antibiotic resistance is relatively uncommon in N. meningitidis isolates but, due to the rapid onset of disease in susceptible hosts, the mortality rate remains approx. 10%. Additionally, patients who survive meningococcal disease often endure numerous debilitating sequelae. N. meningitidis strains are classified primarily into serogroups based on the type of polysaccharide capsule expressed. In total, 13 serogroups have been described; however, the majority of disease is caused by strains belonging to one of only five serogroups. Although vaccines have been developed against some of these, a universal meningococcal vaccine remains a challenge due to successful immune evasion strategies of the organism, including mimicry of host structures as well as frequent antigenic variation. N. meningitidis express a range of virulence factors including capsular polysaccharide, lipopolysaccharide and a number of surface-expressed adhesive proteins. Variation of these surface structures is necessary for meningococci to evade killing by host defence mechanisms. Nonetheless, adhesion to host cells and tissues needs to be maintained to enable colonization and ensure bacterial survival in the niche. The aims of the present review are to provide a brief outline of meningococcal carriage, disease and burden to society. With this background, we discuss several bacterial strategies that may enable its survival in the human respiratory tract during colonization and in the blood during infection. We also examine several known meningococcal adhesion mechanisms and conclude with a section on the potential processes that may operate in vivo as meningococci progress from the respiratory niche through the blood to reach the central nervous system.
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72
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Kesanopoulos K, Tzanakaki G, Sioumala M, Kourea-Kremastinou J. Direct application of variable number tandem repeats polymerase chain reaction in clinical samples obtained from patients with meningococcal disease. Diagn Microbiol Infect Dis 2010; 66:124-7. [DOI: 10.1016/j.diagmicrobio.2008.05.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Revised: 05/16/2008] [Accepted: 05/26/2008] [Indexed: 11/24/2022]
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Clonal distribution of disease-associated and healthy carrier isolates of Neisseria meningitidis between 1983 and 2005 in Cuba. J Clin Microbiol 2009; 48:802-10. [PMID: 20042619 DOI: 10.1128/jcm.01653-09] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In response to epidemic levels of serogroup B meningococcal disease in Cuba during the 1980s, the VA-MENGOC-BC vaccine was developed and introduced into the National Infant Immunization Program in 1991. Since then the incidence of meningococcal disease in Cuba has returned to the low levels recorded before the epidemic. A total of 420 Neisseria meningitidis strains collected between 1983 and 2005 in Cuba were analyzed by multilocus sequence typing (MLST). The set of strains comprised 167 isolated from disease cases and 253 obtained from healthy carriers. By MLST analysis, 63 sequence types (STs) were identified, and 32 of these were reported to be a new ST. The Cuban isolates were associated with 12 clonal complexes; and the most common were ST-32 (246 isolates), ST-53 (86 isolates), and ST-41/44 (36 isolates). This study also showed that the application of VA-MENGOC-BC, the Cuban serogroup B and C vaccine, reduced the frequency and diversity of hypervirulent clonal complexes ST-32 (vaccine serogroup B type-strain) and ST-41/44 and also affected other lineages. Lineages ST-8 and ST-11 were no longer found during the postvaccination period. The vaccine also affected the genetic composition of the carrier-associated meningococcal isolates. The number of carrier isolates belonging to hypervirulent lineages decreased significantly after vaccination, and ST-53, a sequence type common in carriers, became the predominant ST.
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74
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Frequency of factor H-binding protein modular groups and susceptibility to cross-reactive bactericidal activity in invasive meningococcal isolates. Vaccine 2009; 28:2122-9. [PMID: 20044056 DOI: 10.1016/j.vaccine.2009.12.027] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2009] [Revised: 12/03/2009] [Accepted: 12/14/2009] [Indexed: 11/22/2022]
Abstract
Meningococcal factor H-binding protein (fHbp) is a promising vaccine candidate that elicits serum bactericidal antibodies in humans. Based on sequence variability of the entire protein, fHbp has been divided into three variant groups or two sub-families. We recently reported that the fHbp architecture was modular, consisting of five variable segments, each encoded by genes from one of two lineages. Based on combinations of segments from different lineages, all 70 known fHbp sequence variants could be classified into one of six modular groups. In this study, we analyzed sequences of 172 new fHbp variants that were available from public databases. All but three variants could be classified into one of the six previously described modular groups. Among systematically collected invasive group B isolates from the U.S. and Europe, modular group I overall was most common (60%) but group IV (natural chimeras) accounted for 23% of UK isolates and <1% of U.S. isolates (P<0.0001). Mouse antisera to recombinant fHbp from each of the modular groups showed modular group-specific bactericidal activity against strains with low fHbp expression but had broader activity against strains with higher fHbp expression. Thus both modular group and relative expression of fHbp affected strain susceptibility to anti-fHbp bactericidal activity. The results confirmed the modular architecture of fHbp and underscored its importance for the design of broadly protective group B vaccines in different regions.
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75
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Brehony C, Wilson DJ, Maiden MCJ. Variation of the factor H-binding protein of Neisseria meningitidis. MICROBIOLOGY (READING, ENGLAND) 2009; 155:4155-4169. [PMID: 19729409 PMCID: PMC2801853 DOI: 10.1099/mic.0.027995-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 08/13/2009] [Accepted: 08/27/2009] [Indexed: 12/29/2022]
Abstract
There is currently no comprehensive meningococcal vaccine, due to difficulties in immunizing against organisms expressing serogroup B capsules. To address this problem, subcapsular antigens, particularly the outer-membrane proteins (OMPs), are being investigated as candidate vaccine components. If immunogenic, however, such antigens are often antigenically variable, and knowledge of the extent and structuring of this diversity is an essential part of vaccine formulation. Factor H-binding protein (fHbp) is one such protein and is included in two vaccines under development. A survey of the diversity of the fHbp gene and the encoded protein in a representative sample of meningococcal isolates confirmed that variability in this protein is structured into two or three major groups, each with a substantial number of alleles that have some association with meningococcal clonal complexes and serogroups. A unified nomenclature scheme was devised to catalogue this diversity. Analysis of recombination and selection on the allele sequences demonstrated that parts of the gene are subject to positive selection, consistent with immune selection on the protein generating antigenic variation, particularly in the C-terminal region of the peptide sequence. The highest levels of selection were observed in regions corresponding to epitopes recognized by previously described bactericidal monoclonal antibodies.
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MESH Headings
- Alleles
- Amino Acid Sequence
- Antigens, Bacterial/chemistry
- Antigens, Bacterial/genetics
- Antigens, Bacterial/immunology
- Bacterial Proteins/chemistry
- Bacterial Proteins/genetics
- Bacterial Proteins/immunology
- Base Sequence
- DNA Primers/genetics
- DNA, Bacterial/genetics
- Genes, Bacterial
- Genetic Variation
- Humans
- Meningococcal Infections/microbiology
- Meningococcal Vaccines/genetics
- Meningococcal Vaccines/immunology
- Models, Molecular
- Molecular Sequence Data
- Neisseria meningitidis/classification
- Neisseria meningitidis/genetics
- Neisseria meningitidis/immunology
- Neisseria meningitidis, Serogroup A/classification
- Neisseria meningitidis, Serogroup A/genetics
- Neisseria meningitidis, Serogroup A/immunology
- Neisseria meningitidis, Serogroup B/classification
- Neisseria meningitidis, Serogroup B/genetics
- Neisseria meningitidis, Serogroup B/immunology
- Recombination, Genetic
- Selection, Genetic
- Sequence Homology, Amino Acid
- Serotyping
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Affiliation(s)
- Carina Brehony
- Department of Zoology, University of Oxford, OX1 3PS, UK
| | - Daniel J. Wilson
- Department of Human Genetics, University of Chicago, 920 East 58th Street, CLSC #410, Chicago, IL 60637, USA
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76
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Abad R, Agudelo CI, Brandileone MC, Chanto G, Gabastou JM, Hormazabal JC, O Gorla MC, Maldonado A, Moreno J, Muros-Le Rouzic E, Lersch R, Regueira M, Salcedo C, Sorhouet C, Vázquez JA. Molecular characterization of invasive serogroup Y Neisseria meningitidis strains isolated in the Latin America region. J Infect 2009; 59:104-14. [PMID: 19576638 DOI: 10.1016/j.jinf.2009.06.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2009] [Revised: 06/02/2009] [Accepted: 06/02/2009] [Indexed: 11/16/2022]
Abstract
OBJECTIVES To improve the understanding of serogroup Y invasive meningococcal disease (IMD) in Latin America, particularly IMD molecular epidemiology; 166 Y serogroup isolates received at the National Reference Laboratories of Argentina, Brazil, Chile, Colombia, and Costa Rica during 2000-2006 were characterized by their molecular markers. METHODS This analysis included serological assays to determine serogroup/serotype/serosubtype, DNA sequencing and genotyping of the porB and/or porA genes, multilocus sequence typing (MLST) and fetA allele determination. RESULTS Sixteen different antigenic combinations were observed. Sixty-two (37.3%) isolates were NT:P1.5 and 36 (21.7%) isolates were 14:NST. Thirty-two different STs appeared, but 3 STs (ST-1624, ST-23, and ST-5770) accounted for 69.9% (116) of the strains. Most of the IMD isolates belonged to the ST-23, ST-167 clonal complexes or the group composed by ST-5770 and related STs. CONCLUSIONS Isolates obtained in Colombia and Costa Rica were similar to that of the United States, in that most sequence types belonged to the ST-23 clonal complex. IMD isolates found in Argentina appear to be the result of an independent event and did not spread from nearby countries, being the sequence type ST-1624 (ST-167 clonal complex) the most frequently found. We were unable to correlate an antigenic shift of outer membrane proteins with an increase of serogroup Y meningococcal cases in our collection of isolates.
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Affiliation(s)
- Raquel Abad
- Reference Laboratory for Meningococci, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Ctra Majadahonda-Pozuelo, Km2, 28220 Majadahonda, Madrid, Spain
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77
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Abstract
As reviewed in this paper, meningococcal disease epidemiology varies substantially by geographic area and time. The disease can occur as sporadic cases, outbreaks, and large epidemics. Surveillance is crucial for understanding meningococcal disease epidemiology, as well as the need for and impact of vaccination. Despite limited data from some regions of the world and constant change, current meningococcal disease epidemiology can be summarized by region. By far the highest incidence of meningococcal disease occurs in the meningitis belt of sub-Saharan Africa. During epidemics, the incidence can approach 1000 per 100,000, or 1% of the population. Serogroup A has been the most important serogroup in this region. However, serogroup C disease has also occurred, as has serogroup X disease and, most recently, serogroup W-135 disease. In the Americas, the reported incidence of disease, in the range of 0.3-4 cases per 100,000 population, is much lower than in the meningitis belt. In addition, in some countries such as the United States, the incidence is at an historical low. The bulk of the disease in the Americas is caused by serogroups C and B, although serogroup Y causes a substantial proportion of infections in some countries and W-135 is becoming increasingly problematic as well. The majority of meningococcal disease in European countries, which ranges in incidence from 0.2 to 14 cases per 100,000, is caused by serogroup B strains, particularly in countries that have introduced serogroup C meningococcal conjugate vaccines. Serogroup B also predominates in Australia and New Zealand, in Australia because of the control of serogroup C disease through vaccination and in New Zealand because of a serogroup B epidemic. Based on limited data, most disease in Asia is caused by serogroup A and C strains. Although this review summarizes the current status of meningococcal disease epidemiology, the dynamic nature of this disease requires ongoing surveillance both to provide data for vaccine formulation and vaccine policy and to monitor the impact of vaccines following introduction.
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78
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Caugant DA, Maiden MCJ. Meningococcal carriage and disease--population biology and evolution. Vaccine 2009; 27 Suppl 2:B64-70. [PMID: 19464092 PMCID: PMC2719693 DOI: 10.1016/j.vaccine.2009.04.061] [Citation(s) in RCA: 264] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Meningococcal disease occurs worldwide with incidence rates varying from 1 to 1000 cases per 100,000. The causative organism, Neisseria meningitidis, is an obligate commensal of humans, which normally colonizes the mucosa of the upper respiratory tract without causing invasive disease, a phenomenon known as carriage. Studies using molecular methods have demonstrated the extensive genetic diversity of meningocococci isolated from carriers, in contrast to a limited number of genetic types, known as the hyperinvasive lineages, associated with invasive disease. Population and evolutionary models that invoke positive selection can be used to resolve the apparent paradox of virulent lineages persisting during the global spread of a non-clonal and normally commensal bacterium. The application of insights gained from studies of meningococcal population biology and evolution is important in understanding the spread of disease, as well as in vaccine development and implementation, especially with regard to the challenge of producing comprehensive vaccines based on sub-capsular antigens and measuring their effectiveness.
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Affiliation(s)
- Dominique A Caugant
- WHO Collaborating Centre for Reference and Research on Meningococci, Norwegian Institute of Public Health, Oslo, Norway.
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79
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van Ulsen P, Kuhn K, Prinz T, Legner H, Schmid P, Baumann C, Tommassen J. Identification of proteins of
Neisseria meningitidis
induced under iron-limiting conditions using the isobaric tandem mass tag (TMT) labeling approach. Proteomics 2009; 9:1771-81. [DOI: 10.1002/pmic.200800642] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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80
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Jacobsson S, Hedberg ST, Mölling P, Unemo M, Comanducci M, Rappuoli R, Olcén P. Prevalence and sequence variations of the genes encoding the five antigens included in the novel 5CVMB vaccine covering group B meningococcal disease. Vaccine 2009; 27:1579-84. [PMID: 19162117 DOI: 10.1016/j.vaccine.2008.12.052] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2008] [Revised: 12/19/2008] [Accepted: 12/28/2008] [Indexed: 11/25/2022]
Abstract
During the recent years, projects are in progress for designing broad-range non-capsular-based meningococcal vaccines, covering also serogroup B isolates. We have examined three genes encoding antigens (NadA, GNA1030 and GNA2091) included in a novel vaccine, i.e. the 5 Component Vaccine against Meningococcus B (5CVMB), in terms of gene prevalence and sequence variations. These data were combined with the results from a similar study, examining the two additional antigens included in the 5CVMB (fHbp and GNA2132). nadA and fHbp v. 1 were present in 38% (n=36), respectively 71% (n=67) of the isolates, whereas gna2132, gna1030 and gna2091 were present in all the Neisseria meningitidis isolates tested (n=95). The level of amino acid conservation was relatively high in GNA1030 (93%), GNA2091 (92%), and within the main variants of NadA and fHbp. GNA2132 (54% of the amino acids conserved) appeared to be the most diversified antigen. Consequently, the theoretical coverage of the 5CVMB antigens and the feasibility to use these in a broad-range meningococcal vaccine is appealing.
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Affiliation(s)
- Susanne Jacobsson
- National Reference Laboratory for Pathogenic Neisseria, Department of Clinical Microbiology, Orebro University Hospital, SE-701 85 Orebro, Sweden.
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81
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Abstract
Multilocus sequence typing (MLST) was first proposed in 1998 as a typing approach that enables the unambiguous characterization of bacterial isolates in a standardized, reproducible, and portable manner using the human pathogen Neisseria meningitidis as the exemplar organism. Since then, the approach has been applied to a large and growing number of organisms by public health laboratories and research institutions. MLST data, shared by investigators over the world via the Internet, have been successfully exploited in applications ranging from molecular epidemiological investigations to population biology and evolutionary analyses. This chapter describes the practical steps in the development and application of an MLST scheme and some of the common tools and techniques used to obtain the maximum benefit from the data. Considerations pertinent to the implementation of high-capacity MLST projects (i.e., those involving thousands of isolates) are discussed.
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Affiliation(s)
- Ana Belén Ibarz Pavón
- Department of Zoology and Peter Medawar Building for Pathogen Research, University of Oxford, South Parks Road, , Oxford, UK
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82
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Meningococcal outer membrane vesicle vaccines derived from mutant strains engineered to express factor H binding proteins from antigenic variant groups 1 and 2. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2008; 16:156-62. [PMID: 19109451 DOI: 10.1128/cvi.00403-08] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Meningococcal outer membrane vesicle (OMV) vaccines, which are treated with detergents to decrease endotoxin activity, are safe and effective in humans. However, the vaccines elicit serum bactericidal antibody responses largely directed against PorA, which is antigenically variable. We previously prepared a native (non-detergent-treated) OMV vaccine from a mutant of group B strain H44/76 in which the lpxL1 gene was inactivated, which resulted in penta-acylated lipid A with attenuated endotoxin activity. To enhance protection, we overexpressed factor H binding protein (fHbp) from the antigenic variant 1 group. The vaccine elicited broad serum bactericidal antibody responses in mice against strains with fHbp variant 1 (approximately 70% of group B isolates) but not against strains with variant 2 or 3. In the present study, we constructed a mutant of group B strain NZ98/254 with attenuated endotoxin that expressed both endogenous variant 1 and heterologous fHbp variant 2. A mixture of the two native OMV vaccines from the H44/76 and NZ98/254 mutants stimulated proinflammatory cytokine responses by human peripheral blood mononuclear cells similar to those stimulated by control, detergent-treated OMV vaccines from the wild-type strains. In mice, the mixture of the two native OMV vaccines elicited broad serum bactericidal antibody responses against strains with heterologous PorA and fHbp in the variant 1, 2, or 3 group. By adsorption studies, the principal bactericidal antibody target was determined to be fHbp. Thus, native OMV vaccines from mutants expressing fHbp variants have the potential to be safe for humans and to confer broad protection against meningococcal disease from strains expressing fHbp from each of the antigenic variant groups.
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83
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HOWITZ MICHAEL, LAMBERTSEN LOTTE, MØLBAK KÅRE, CHRISTENSEN JENSJØRGEN. National case-control study on risk of death and Neisseria meningitidissequence types in Denmark, 2000-2007. APMIS 2008; 116:1107-15. [DOI: 10.1111/j.1600-0463.2008.01230.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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84
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Maiden MC. Population genomics: diversity and virulence in the Neisseria. Curr Opin Microbiol 2008; 11:467-71. [PMID: 18822386 PMCID: PMC2612085 DOI: 10.1016/j.mib.2008.09.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Accepted: 09/02/2008] [Indexed: 01/28/2023]
Abstract
Advances in high-throughput nucleotide sequencing and bioinformatics make the study of genomes at the population level feasible. Preliminary population genomic studies have explored the relationships among three closely related bacteria, Neisseria meningitidis, Neisseria gonorrhoeae and Neisseria lactamica, which exhibit very different phenotypes with respect to human colonisation. The data obtained have been especially valuable in the establishing of the role of horizontal genetic exchange in bacterial speciation and shaping population structure. In the meningococcus, they have been used to define invasive genetic types, search for virulence factors and potential vaccine components and investigate the effects of vaccines on population structure. These are generic approaches and their application to the Neisseria provides a foretaste for their application to the wider bacterial world.
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Affiliation(s)
- Martin Cj Maiden
- Department of Zoology, South Parks Road, Oxford OX1 2PS, United Kingdom.
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85
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Weidlich L, Baethgen LF, Mayer LW, Moraes C, Klein CC, Nunes LS, Rios SDS, Kmetzsch CI, Rossetti ML, Zaha A. High prevalence of Neisseria meningitidis hypervirulent lineages and emergence of W135:P1.5,2:ST-11 clone in Southern Brazil. J Infect 2008; 57:324-31. [DOI: 10.1016/j.jinf.2008.07.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 07/25/2008] [Accepted: 07/29/2008] [Indexed: 11/17/2022]
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86
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Telford JL. Bacterial genome variability and its impact on vaccine design. Cell Host Microbe 2008; 3:408-16. [PMID: 18541217 DOI: 10.1016/j.chom.2008.05.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2008] [Revised: 05/16/2008] [Accepted: 05/16/2008] [Indexed: 11/16/2022]
Abstract
The majority of currently available successful vaccines induce host responses against antigens that are highly conserved in the targeted pathogens. The diphtheria, tetanus, and pertussis vaccines confer protection by inducing neutralizing antibodies to the conserved bacterial toxins that are the major virulence factors. The Hemophilus influenzae B vaccine induces responses to conserved epitopes in the sugar structure of the bacterial capsular polysaccharide. However, the efficacy of more recently developed vaccines is limited by antigen variation, which also presents a challenge for future vaccine development. This review will explore bacterial genome variability and its impact on vaccine development.
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Affiliation(s)
- John L Telford
- Novartis Vaccines and Diagnostics Srl, Via Fiorentina 1, 53100 Siena, Italy.
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87
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Russell JE, Urwin R, Gray SJ, Fox AJ, Feavers IM, Maiden MCJ. Molecular epidemiology of meningococcal disease in England and Wales 1975-1995, before the introduction of serogroup C conjugate vaccines. MICROBIOLOGY-SGM 2008; 154:1170-1177. [PMID: 18375809 PMCID: PMC2885627 DOI: 10.1099/mic.0.2007/014761-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A comprehensive meningococcal vaccine is yet to be developed. In the absence of a vaccine that immunizes against the serogroup B capsular polysaccharide, this can only be achieved by targeting subcapsular antigens, and a number of outer-membrane proteins (OMPs) are under consideration as candidates. A major obstacle to the development of such a vaccine is the antigenic diversity of these OMPs, and obtaining population data that accurately identify and catalogue these variants is an important component of vaccine design. The recently proposed meningococcal molecular strain-typing scheme indexes the diversity of two OMPs, PorA and FetA, that are vaccine candidates, as well as the capsule and multilocus sequence type. This scheme was employed to survey 323 meningococci isolated from invasive disease in England and Wales from 1975 to 1995, before the introduction of meningococcal conjugated serogroup C polysaccharide vaccines in 1999. The eight-locus typing scheme provided high typeability (99.4 %) and discrimination (Simpson's diversity index 0.94–0.99). The data showed cycling of meningococcal genotypes and antigenic types in the absence of planned interventions. Notwithstanding high genetic and antigenic diversity, most of the isolates belonged to one of seven clonal complexes, with 11 predominant strain types. Combinations of PorA and FetA, chosen on the basis of their prevalence over time, generated vaccine recipes that included protein variants found in 80 % or more of the disease isolates for this time period. If adequate immune responses can be generated, these results suggest that control of meningococcal disease with relatively simple protein component vaccines may be possible.
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Affiliation(s)
- Joanne E Russell
- Division of Bacteriology, National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Herts EN6 3QG, UK.,Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, OX1 3SY, UK
| | - Rachel Urwin
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA.,Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, OX1 3SY, UK
| | - Stephen J Gray
- Meningococcal Reference Unit, Health Protection Agency, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
| | - Andrew J Fox
- Meningococcal Reference Unit, Health Protection Agency, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
| | - Ian M Feavers
- Division of Bacteriology, National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Herts EN6 3QG, UK
| | - Martin C J Maiden
- Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, OX1 3SY, UK
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88
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Maiden MCJ, Ibarz-Pavón AB, Urwin R, Gray SJ, Andrews NJ, Clarke SC, Walker AM, Evans MR, Kroll JS, Neal KR, Ala'aldeen DAA, Crook DW, Cann K, Harrison S, Cunningham R, Baxter D, Kaczmarski E, Maclennan J, Cameron JC, Stuart JM. Impact of meningococcal serogroup C conjugate vaccines on carriage and herd immunity. J Infect Dis 2008; 197:737-43. [PMID: 18271745 DOI: 10.1086/527401] [Citation(s) in RCA: 346] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND In 1999, meningococcal serogroup C conjugate (MCC) vaccines were introduced in the United Kingdom for those under 19 years of age. The impact of this intervention on asymptomatic carriage of meningococci was investigated to establish whether serogroup replacement or protection by herd immunity occurred. METHODS Multicenter surveys of carriage were conducted during vaccine introduction and on 2 successive years, resulting in a total of 48,309 samples, from which 8599 meningococci were isolated and characterized by genotyping and phenotyping. RESULTS A reduction in serogroup C carriage (rate ratio, 0.19) was observed that lasted at least 2 years with no evidence of serogroup replacement. Vaccine efficacy against carriage was 75%, and vaccination had a disproportionate impact on the carriage of sequence type (ST)-11 complex serogroup C meningococci that (rate ratio, 0.06); these meningococci also exhibited high rates of capsule expression. CONCLUSIONS The impact of vaccination with MCC vaccine on the prevalence of carriage of group C meningococci was consistent with herd immunity. The high impact on the carriage of ST-11 complex serogroup C could be attributed to high levels of capsule expression. High vaccine efficacy against disease in young children, who were not protected long-term by the schedule initially used, is attributed to the high vaccine efficacy against carriage in older age groups.
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Affiliation(s)
- Martin C J Maiden
- Dept. of Zoology, John Radcliffe Hospital, Oxford University, Oxford, United Kingdom.
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89
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Genotypic characterization of Neisseria meningitidis serogroup B strains circulating in China. J Infect 2008; 56:211-8. [DOI: 10.1016/j.jinf.2007.12.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Revised: 12/10/2007] [Accepted: 12/10/2007] [Indexed: 11/20/2022]
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90
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Demuth A, Aharonowitz Y, Bachmann TT, Blum-Oehler G, Buchrieser C, Covacci A, Dobrindt U, Emödy L, van der Ende A, Ewbank J, Fernández LA, Frosch M, García-Del Portillo F, Gilmore MS, Glaser P, Goebel W, Hasnain SE, Heesemann J, Islam K, Korhonen T, Maiden M, Meyer TF, Montecucco C, Oswald E, Parkhill J, Pucciarelli MG, Ron E, Svanborg C, Uhlin BE, Wai SN, Wehland J, Hacker J. Pathogenomics: an updated European Research Agenda. INFECTION GENETICS AND EVOLUTION 2008; 8:386-93. [PMID: 18321793 DOI: 10.1016/j.meegid.2008.01.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Accepted: 01/14/2008] [Indexed: 01/16/2023]
Abstract
The emerging genomic technologies and bioinformatics provide novel opportunities for studying life-threatening human pathogens and to develop new applications for the improvement of human and animal health and the prevention, treatment, and diagnosis of infections. Based on the ecology and population biology of pathogens and related organisms and their connection to epidemiology, more accurate typing technologies and approaches will lead to better means of disease control. The analysis of the genome plasticity and gene pools of pathogenic bacteria including antigenic diversity and antigenic variation results in more effective vaccines and vaccine implementation programs. The study of newly identified and uncultivated microorganisms enables the identification of new threats. The scrutiny of the metabolism of the pathogen in the host allows the identification of new targets for anti-infectives and therapeutic approaches. The development of modulators of host responses and mediators of host damage will be facilitated by the research on interactions of microbes and hosts, including mechanisms of host damage, acute and chronic relationships as well as commensalisms. The study of multiple pathogenic and non-pathogenic microbes interacting in the host will improve the management of multiple infections and will allow probiotic and prebiotic interventions. Needless to iterate, the application of the results of improved prevention and treatment of infections into clinical tests will have a positive impact on the management of human and animal disease. The Pathogenomics Research Agenda draws on discussions with experts of the Network of Excellence "EuroPathoGenomics" at the management board meeting of the project held during 18-21 April 2007, in the Villa Vigoni, Menaggio, Italy. Based on a proposed European Research Agenda in the field of pathogenomics by the ERA-NET PathoGenoMics the meeting's participants updated the established list of topics as the research agenda for the future.
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Affiliation(s)
- Andreas Demuth
- Institut für Molekulare Infektionsbiologie, Röntgenring 11, 97070 Würzburg, Germany
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91
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van Belkum A, Tassios PT, Dijkshoorn L, Haeggman S, Cookson B, Fry NK, Fussing V, Green J, Feil E, Gerner-Smidt P, Brisse S, Struelens M. Guidelines for the validation and application of typing methods for use in bacterial epidemiology. Clin Microbiol Infect 2007; 13 Suppl 3:1-46. [PMID: 17716294 DOI: 10.1111/j.1469-0691.2007.01786.x] [Citation(s) in RCA: 530] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
For bacterial typing to be useful, the development, validation and appropriate application of typing methods must follow unified criteria. Over a decade ago, ESGEM, the ESCMID (Europen Society for Clinical Microbiology and Infectious Diseases) Study Group on Epidemiological Markers, produced guidelines for optimal use and quality assessment of the then most frequently used typing procedures. We present here an update of these guidelines, taking into account the spectacular increase in the number and quality of typing methods made available over the past decade. Newer and older, phenotypic and genotypic methods for typing of all clinically relevant bacterial species are described according to their principles, advantages and disadvantages. Criteria for their evaluation and application and the interpretation of their results are proposed. Finally, the issues of reporting, standardisation, quality assessment and international networks are discussed. It must be emphasised that typing results can never stand alone and need to be interpreted in the context of all available epidemiological, clinical and demographical data relating to the infectious disease under investigation. A strategic effort on the part of all workers in the field is thus mandatory to combat emerging infectious diseases, as is financial support from national and international granting bodies and health authorities.
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Affiliation(s)
- A van Belkum
- Erasmus MC, Department of Medical Microbiology and Infectious Diseases, Rotterdam, The Netherlands.
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92
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Trotter CL, Ramsay ME. Vaccination against meningococcal disease in Europe: review and recommendations for the use of conjugate vaccines. FEMS Microbiol Rev 2006; 31:101-7. [PMID: 17168998 DOI: 10.1111/j.1574-6976.2006.00053.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
At the end of 2005, six European countries had implemented public immunization campaigns with serogroup C conjugate vaccines, and all had experienced substantial declines in the incidence of serogroup C disease. A quadrivalent ACWY meningococcal vaccine is in use in the USA, but serogroup A is extremely rare in Europe and serogroups Y and W135 are infrequent causes of disease. This paper outlines recommendations on the use of conjugate vaccines in Europe based on the experience with meningococcal C conjugate (MCC) vaccines so far.
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Affiliation(s)
- Caroline L Trotter
- Immunization Department, Health Protection Agency Centre for Infections, London, UK
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