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Taha MK, Alonso JM. Corticosteroids for bacterial meningitis. N Engl J Med 2008; 358:1400; author reply 1400-1. [PMID: 18376431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
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152
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Taha MK, Alonso JM. Molecular epidemiology of infectious diseases: the example of meningococcal disease. Res Microbiol 2007; 159:62-6. [PMID: 18243667 DOI: 10.1016/j.resmic.2007.11.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2007] [Accepted: 11/30/2007] [Indexed: 11/18/2022]
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153
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Zarantonelli ML, Szatanik M, Giorgini D, Hong E, Huerre M, Guillou F, Alonso JM, Taha MK. Transgenic mice expressing human transferrin as a model for meningococcal infection. Infect Immun 2007; 75:5609-14. [PMID: 17893132 PMCID: PMC2168318 DOI: 10.1128/iai.00781-07] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 07/04/2007] [Accepted: 09/13/2007] [Indexed: 11/20/2022] Open
Abstract
The pathogenesis of meningococcal disease is poorly understood due to the lack of a relevant animal model. Moreover, the use of animal models is not optimal as most meningococcal virulence determinants recognize receptors that are specifically expressed in human tissues. One major element of the host specificity is the system of meningococcal iron uptake by transferrin-binding proteins that bind specifically human transferrin but not murine transferrin. We developed a new mouse model for experimental meningococcal infection using transgenic mice expressing human transferrin. Intraperitoneal challenge of transgenic mice induced bacteremia for at least 48 h with an early stage of multiplication, whereas the initial inoculum was rapidly cleared from blood in wild-type mice. Inflammation in the subarachnoidal space with a high influx of polymorphonuclear cells was observed only in transgenic mice. Meningococcal mutants that were unable to use transferrin as a source of iron were rapidly cleared from both wild-type and transgenic mice. Thus, transgenic mice expressing human transferrin may represent an important advance as a new mouse model for in vivo studies of meningococcal virulence and immunogenicity factors.
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Taha MK, Vázquez JA, Hong E, Bennett DE, Bertrand S, Bukovski S, Cafferkey MT, Carion F, Christensen JJ, Diggle M, Edwards G, Enríquez R, Fazio C, Frosch M, Heuberger S, Hoffmann S, Jolley KA, Kadlubowski M, Kechrid A, Kesanopoulos K, Kriz P, Lambertsen L, Levenet I, Musilek M, Paragi M, Saguer A, Skoczynska A, Stefanelli P, Thulin S, Tzanakaki G, Unemo M, Vogel U, Zarantonelli ML. Target gene sequencing to characterize the penicillin G susceptibility of Neisseria meningitidis. Antimicrob Agents Chemother 2007; 51:2784-92. [PMID: 17517841 PMCID: PMC1932518 DOI: 10.1128/aac.00412-07] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Clinical isolates of Neisseria meningitidis with reduced susceptibility to penicillin G (intermediate isolates, Pen(I)) harbor alterations in the penA gene encoding the penicillin binding protein 2 (PBP2). A 402-bp DNA fragment in the 3' half of penA was sequenced from a collection of 1,670 meningococcal clinical isolates from 22 countries that spanned 60 years. Phenotyping, genotyping, and the determination of MICs of penicillin G were also performed. A total of 139 different penA alleles were detected with 38 alleles that were highly related, clustered together in maximum-likelihood analysis and corresponded to the penicillin G-susceptible isolates. The remaining 101 penA alleles were highly diverse, corresponded to different genotypes or phenotypes, and accounted for 38% of isolates, but no clonal expansion was detected. Analysis of the altered alleles that were represented by at least five isolates showed high correlation with the Pen(I) phenotype. The deduced amino acid sequence of the corresponding PBP2 comprised five amino acid residues that were always altered. This correlation was not complete for rare alleles, suggesting that other mechanisms may also be involved in conferring reduced susceptibility to penicillin. Evidence of mosaic structures through events of interspecies recombination was also detected in altered alleles. A new website was created based on the data from this work (http://neisseria.org/nm/typing/penA). These data argue for the use of penA sequencing to identify isolates with reduced susceptibility to penicillin G and as a tool to improve typing of meningococcal isolates, as well as to analyze DNA exchange among Neisseria species.
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Boisier P, Nicolas P, Djibo S, Taha MK, Jeanne I, Maïnassara HB, Tenebray B, Kairo KK, Giorgini D, Chanteau S. Meningococcal meningitis: unprecedented incidence of serogroup X-related cases in 2006 in Niger. Clin Infect Dis 2007; 44:657-63. [PMID: 17278055 DOI: 10.1086/511646] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2006] [Accepted: 11/25/2006] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND In Niger, epidemic meningococcal meningitis is primarily caused by Neisseria meningitidis (Nm) serogroup A. However, since 2002, Nm serogroup W135 has been considered to be a major threat that has not yet been realized, and an unprecedented incidence of Nm serogroup X (NmX) meningitis was observed in 2006. METHODS Meningitis surveillance in Niger is performed on the basis of reporting of clinically suspected cases. Cerebrospinal fluid specimens are sent to the reference laboratory in Niamey, Niger. Culture, latex agglutination, and polymerase chain reaction are used whenever appropriate. Since 2004, after the addition of a polymerase chain reaction-based nonculture assay that was developed to genogroup isolates of NmX, polymerase chain reaction testing allows for the identification of Nm serogroup A, Nm serogroup B, Nm serogroup C, NmX, Nm serogroup Y, and Nm serogroup W135. RESULTS From January to June 2006, a total of 4185 cases of meningitis were reported, and 2905 cerebrospinal fluid specimens were laboratory tested. NmX meningitis represented 51% of 1139 confirmed cases of meningococcal meningitis, but in southwestern Niger, it represented 90%. In the agglomeration of Niamey, the reported cumulative incidence of meningitis was 73 cases per 100,000 population and the cumulative incidence of confirmed NmX meningitis was 27.5 cases per 100,000 population (74.6 cases per 100,000 population in children aged 5-9 years). NmX isolates had the same phenotype (X : NT : P1.5), and all belonged to the same sequence type (ST-181) as the NmX isolates that were circulating in Niamey in the 1990s. Nm serogroup W135 represented only 2.1% of identified meningococci. CONCLUSIONS This is, to our knowledge, the first report of such a high incidence of NmX meningitis, although an unusually high incidence of NmX meningitis was also observed in the 1990s in Niamey. The increasing incidence of NmX meningitis is worrisome, because no vaccine has been developed against this serogroup. Countries in the African meningitis belt must prepare to face this potential new challenge.
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Taha MK, Fox A. Quality assessed nonculture techniques for detection and typing of meningococci. FEMS Microbiol Rev 2007; 31:37-42. [PMID: 17233634 DOI: 10.1111/j.1574-6976.2006.00054.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
PCR protocols are increasingly used in laboratories worldwide for the diagnosis and confirmation of invasive meningococcal infection. Protocols are now available for the identification of Neisseria meningitidis, for genogrouping, susceptibility to antibiotics and genotyping of the corresponding isolates. The implementation of quality assurance (QA) schemes and standardization of protocols are required. Diagnostic and confirmatory PCRs should perform consistently in clinical and reference microbiology laboratories. General QA schemes address the issues of sample preparation, PCR laboratory environment, equipment and validation of protocols. Moreover, external QA interlaboratory studies are essential. The European Monitoring Group on Meningococci has provided a good forum to conduct such studies through the development and distribution of samples and protocols for nonculture detection and typing of N. meningitidis.
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Fox AJ, Taha MK, Vogel U. Standardized nonculture techniques recommended for European reference laboratories. FEMS Microbiol Rev 2007; 31:84-8. [PMID: 17147691 DOI: 10.1111/j.1574-6976.2006.00048.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Culture-confirmed diagnosis of meningococcal invasive infections is often hindered by early antibiotic treatment. Nonculture molecular standardized methods are now essential tools for the immediate management of meningococcal infections. The European Monitoring Group on Meningococci (EMGM) recommends the following measures. (1) The implementation of standardized protocols of extraction methods for DNA isolation from clinical specimens for PCR-based identification and genogrouping of Neisseria meningitidis. (2) The use of molecular approaches (sequencing of target genes) for the determination of meningococcal susceptibility to antibiotics, such as sequencing of penA and rpoB genes for susceptibility to penicillin G and rifampicin, respectively. (3) The use of nonculture strain characterization by multilocus sequence typing (MLST) and sequence typing of porA and fetA. These approaches can be implemented either by individual reference laboratories or through collaboration and referral between centres.
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Zarantonelli ML, Huerre M, Taha MK, Alonso JM. Differential role of lipooligosaccharide of Neisseria meningitidis in virulence and inflammatory response during respiratory infection in mice. Infect Immun 2006; 74:5506-12. [PMID: 16988225 PMCID: PMC1594929 DOI: 10.1128/iai.00655-06] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Meningococcal lipooligosaccharide (LOS) induces a strong proinflammatory response in humans during meningococcal infection. We analyzed the role of LOS in the inflammatory response and virulence during the early infectious process in a mouse model of meningococcal respiratory challenge. An lpxA mutant strain (serogroup B) devoid of LOS (strain Z0204) could not persist in the lungs and did not invade the blood. The persistence in the lungs and invasion of the bloodstream by a rfaD mutant expressing truncated LOS with only lipid A and 3-deoxy-d-manno-2-octulosonic acid molecules (strain Z0401) was intermediate between those of the wild-type and Z0204 strains. Both LOS mutants induced acute pneumonia with the presence of infiltrating polymorphonuclear leukocytes in lungs. Although tumor necrosis factor alpha production was reduced in mice infected with the mutant of devoid LOS, both LOS mutants induced production of other proinflammatory cytokines, such as interleukin-1beta (IL-1beta), IL-6, and the murine IL-8 homolog KC. Together, these results suggest that meningococcal LOS plays a role during the early infectious and invasive process, and they further confirm that other, nonlipopolysaccharide components of Neisseria meningitidis may significantly contribute to the inflammatory reaction of the host.
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Taha MK, Zarantonelli ML, Ruckly C, Giorgini D, Alonso JM. Rifampin-resistant Neisseria meningitidis. Emerg Infect Dis 2006; 12:859-60. [PMID: 16710955 PMCID: PMC3374432 DOI: 10.3201/eid1205.051296] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Traoré Y, Njanpop-Lafourcade BM, Adjogble KLS, Lourd M, Yaro S, Nacro B, Drabo A, Parent du Châtelet I, Mueller JE, Taha MK, Borrow R, Nicolas P, Alonso JM, Gessner BD. The rise and fall of epidemic Neisseria meningitidis serogroup W135 meningitis in Burkina Faso, 2002-2005. Clin Infect Dis 2006; 43:817-22. [PMID: 16941360 DOI: 10.1086/507339] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Accepted: 06/09/2006] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND During the period 2001-2002, Burkina Faso reported its first meningitis epidemic due to Neisseria meningitidis (Nm) serogroup W135, prompting concerns that this serogroup would persist as a cause of epidemic disease. METHODS During the period 2002-2005, hospital- and population-based surveillances were conducted in 3 districts in Burkina Faso. Etiology was determined by culture, polymerase chain reaction (PCR), and latex agglutination. Reference laboratories determined phenotype and genotype. RESULTS Of 2004 subjects who received a lumbar puncture, 265 were identified as having Nm, including 93 who had Nm serogroup A (NmA) and 146 who had Nm serogroup W135 (NmW135). Over the study period, the proportion of cases due to NmW135 decreased by >75%, primarily because of decreased occurrence among young children and in a single district. During peak epidemic months, the annualized incidence of NmW135 decreased from 146 cases to <1 case per 100,000 population. All but 2 NmW135 isolates were phenotype W135:2a:P1.5,2 (sequence type [ST]-11 clonal complex). All NmA isolates were phenotype A:4:P1-9 (ST-2859 of the ST-5 clonal complex). We identified 1 isolate from serogroup Y (ST-11 clonal complex), 1 isolate from serogroup X that was similar to strains previously associated with epidemic disease, and 1 isolate from serogroup W135 of the newly described ST-4375 complex. CONCLUSIONS For unknown reasons, serogroup W135 achieved epidemic status, primarily among young children, and then largely disappeared over a short time period. The continued circulation of multiple strains with epidemic potential emphasizes the need for ongoing surveillance and the potential benefit of vaccines that are protective across serogroups.
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Rouaud P, Perrocheau A, Taha MK, Sesboué C, Forgues AM, Parent du Châtelet I, Levy-Bruhl D. Prolonged outbreak of B meningococcal disease in the Seine-Maritime department, France, January 2003 to June 2005. Euro Surveill 2006; 11:178-81. [PMID: 16966800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
Between January 2003 and June 2005, an outbreak of meningococcal disease occurred in the department of Seine-Maritime in northern France. Eighty six cases were notified, giving an average annual incidence of 2.7 cases per 100,000 inhabitants, compared with 1.6 in France. An especially affected area was defined as the city of Dieppe and its surrounding area (26 cases, giving an annual incidence of 12 cases per 100,000). This outbreak was due to N. meningitidis phenotype B:14:P1.7,16 belonging to the clonal complex ST-32/ET-5. Over the 31 B14:P1.7,16 cases confirmed by phenotyping methods at the national reference centre for meningococci (CNR, Centre National de Reference des meningocoques) the case-fatality rate (19%) and the proportion of purpura fulminans (42%) were especially high. Teenagers aged between 15 and 19 years and children aged 1 to 9 years were the most affected. In 2003, health authorities put in place enhanced epidemiological surveillance and informed practitioners and population about the disease. In 2004, the national vaccination advisory board studied the opportunity of using a non licensed outer membrane vesicle vaccine developed in Norway which may be effective against the B14:P1.7,16 strain. The Ministry of health decided in 2006 to offer vaccination with this vaccine to people aged 1 to 19 years in Seine-Maritime.
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Rouaud P, Perrocheau A, Taha MK, Sesboué C, Forgues AM, Parent du Châtelet I, Lévy-Bruhl D. Prolonged outbreak of B meningococcal disease in the Seine-Maritime department, France, January 2003 to June 2005. Euro Surveill 2006; 11:3-4. [DOI: 10.2807/esm.11.07.00635-en] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Between January 2003 and June 2005, an outbreak of meningococcal disease occured in the department of Seine-Maritime in northern France. Eighty six cases were notified, giving an average annual incidence of 2.7 cases per 100 000 inhabitants, compared with 1.6 in France. An especially affected area was defined as the city of Dieppe and its surrounding area (26 cases, giving an annual incidence of 12 cases per 100 000). This outbreak was due to N. meningitidis phenotype B:14:P1.7,16 belonging to the clonal complex ST-32/ET-5. Over the 31 B14:P1.7,16 cases confirmed by phenotyping methods at the national reference centre for meningococci (CNR, Centre National de Référence des méningocoques) the case-fatality rate (19%) and the proportion of purpura fulminans (42%) were especially high. Teenagers aged between 15 and 19 years and children aged 1 to 9 years were the most affected. In 2003, health authorities put in place enhanced epidemiological surveillance and informed practitioners and population about the disease. In 2004, the national vaccination advisory board studied the opportunity of using a non licensed outer membrane vesicle vaccine developed in Norway which may be effective against the B14:P1.7,16 strain. The Ministry of health decided in 2006 to offer vaccination with this vaccine to people aged 1 to 19 years in Seine- Maritime.
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Taha MK, Zarantonelli ML, Neri A, Enriquez R, Vázquez JA, Stefanelli P. Interlaboratory comparison of PCR-based methods for detection of penicillin G susceptibility in Neisseria meningitidis. Antimicrob Agents Chemother 2006; 50:887-92. [PMID: 16495247 PMCID: PMC1426420 DOI: 10.1128/aac.50.3.887-892.2006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We carried out a study for the nonculture detection of susceptibility of Neisseria meningitis to penicillin G in three laboratories of the European Monitoring Group on Meningococci (EMGM). Thirteen clinical samples (cerebrospinal fluids) and corresponding bacterial isolates from 13 cases of invasive meningococcal infection were distributed to the three laboratories. The MICs of penicillin G were determined for the isolates. Each laboratory used an "in-house" PCR-based method to determine alterations to the penA gene, which is associated with a reduced susceptibility to penicillin G. Nucleotide sequences from the 3' end of the penA gene were also determined. We observed a good correlation between genotyping of penA and the phenotypic determination (MIC) of susceptibility to penicillin G. The results obtained by the three methods for penA in the samples correlated very well with those obtained in bacterial isolates and with sequence data. The kappa coefficient that was used to estimate the level of agreement between genotypic results varied between 0.65 and 1, indicating a good agreement. This suggests that genotyping can predict susceptibility of N. meningitidis to penicillin G. These data strongly suggest that genotyping of penA should be used to determine meningococcal susceptibility to penicillin G in culture-negative cases. Although the nucleotide sequence of penA may be the gold standard in genotyping of penA, the less expensive PCR-based approach reported in this study may be quicker when a large number of isolates and clinical samples need to be tested.
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Zarantonelli ML, Antignac A, Lancellotti M, Guiyoule A, Alonso JM, Taha MK. Immunogenicity of meningococcal PBP2 during natural infection and protective activity of anti-PBP2 antibodies against meningococcal bacteraemia in mice. J Antimicrob Chemother 2006; 57:924-30. [PMID: 16513914 DOI: 10.1093/jac/dkl066] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE To evaluate the immunogenicity of the meningococcal penicillin-binding protein 2 (PBP2) and its potential as a vaccine candidate. METHODS The immunogenicity of meningococcal PBP2 was investigated using acute and convalescent sera from patients who recovered from meningococcal disease. Sera were tested against purified recombinant PBP2s corresponding to meningococcal isolates of different genetic lineages, of different serogroups and with various susceptibility levels to penicillin G. Mice were vaccinated with recombinant PBP2 and challenged with Neisseria meningitidis. A purified anti-PBP2 rabbit IgG was also used for passive protection experiments in mice. RESULTS Convalescent patients' sera recognized PBP2s from different strains, showing that this protein is immunogenic in meningococcal disease. Vaccination with purified recombinant PBP2 and purified anti-PBP2 rabbit IgG antibody conferred protection against experimental meningococcaemia in mice. CONCLUSION These data argue for considering meningococcal PBP2 as a vaccine candidate.
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Taha MK, Zarantonelli ML, Alonso JM, Naess LM, Holst J, Feiring B, Rosenqvist E. Use of available outer membrane vesicle vaccines to control serogroup B meningococcal outbreaks. Vaccine 2006; 25:2537-8. [PMID: 16460845 DOI: 10.1016/j.vaccine.2005.12.059] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2005] [Accepted: 12/26/2005] [Indexed: 10/25/2022]
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Perrocheau A, Taha MK, Levy-Bruhl D. Epidemiology of invasive meningococcal disease in France in 2003. Euro Surveill 2005; 10:238-41. [PMID: 16371693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
National surveillance of invasive meningococcal disease (IMD) is based on mandatory reporting. The case definition for surveillance notification was changed in mid-2002 to include cases without microbiological confirmation. The IMD alert detection system was enhanced in 2003 with daily reporting and weekly analysis by district, serogroup, and age. Evaluation of the exhaustivity of the surveillance with capture-recapture analysis allowed correcting for underreporting. In 2003, 803 cases were reported. After correction for under-reporting, the estimated incidence was 1.78 / 100,000. After excluding 'new' cases reported with new definition criteria, the 2002-2003 increase was 4%. Incidence decreased with age, with the highest values in infants less than 1 year (20/100,000), children aged between 1 and 2 years (11/100,000) and in teenagers of 17 years old(7/100,000). The overall case fatality rate was 12%. Fifty nine per cent of cases were due to serogroup B, 32% to C, 5% to W135, and 4% to Y and non-groupable meningococci. Patients with purpura fulminans treated with intravenous antibiotics before admission to hospital were shown to have lower fatality rates than those not treated. In 2001-2003, 5 situations required particular attention: two clusters of serogroup B IMD had set off mass prophylaxis, one outbreak due to a specific B IMD clonal complex with high case fatality rate, and two districts crossed the alert threshold for serogroup C IMD, 2/100,000, and mass vaccination was recommended.
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Abstract
Neisseria meningitidis can cause asymptomatic carriage, followed by acquired immunity, or septicaemia, meningitis, septic arthritis or pericarditis. Vaccination induces protective bactericidal antibodies to invasive diseases. Meningococcal capsular polysaccharides are immunoprotective antigens from which vaccines are produced against serogroups A, C, Y and W135, including conjugate vaccines against serogroup C. There is no available vaccine against serogroup B, but outermembrane protein-based vaccines against this serogroup are currently being evaluated. Polysaccharide meningococcal vaccines are effective, but their strictly serogroup-specific efficacy raises concerns about the possible selection of escape variants. Therefore, meningococcal polysaccharide vaccines, either plain or conjugated, are indicated against the clonal expansion of strains whose serogroup has been properly identified and corresponds to the vaccine valence.
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Lancellotti M, Guiyoule A, Ruckly C, Hong E, Alonso JM, Taha MK. Conserved virulence of C to B capsule switched Neisseria meningitidis clinical isolates belonging to ET-37/ST-11 clonal complex. Microbes Infect 2005; 8:191-6. [PMID: 16182586 DOI: 10.1016/j.micinf.2005.06.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2005] [Revised: 06/14/2005] [Accepted: 06/15/2005] [Indexed: 11/23/2022]
Abstract
Capsule switching in Neisseria meningitidis is thought to occur by horizontal DNA exchange between meningococcal strains. Antigenic variants may be generated by allelic replacement of the siaD gene; the variants may then be selected by specific immunity against the capsular antigen. There were several vaccination campaigns against serogroup C in France in 2002, following an increase in the prevalence of invasive isolates of serogroup C of the phenotype C:2a:P1.5 and C:2a:P1.5,2 belonging to the ET-37/ST-11 clonal complex. We evaluated the emergence of capsule variants by the detection of B:2a:P1.5 and B:2a:P1.5,2 meningococcal isolates of the ET-37/ST-11 clonal complex. These isolates were significantly more frequent after the year 2002. Pulsed field gel electrophoresis profiles of the serogroup B (ET-37/ST-11) isolates differed from that of serogroup C (ET-37/ST-11) isolates by the bands that harbor the siaD genes responsible for the serogroup specificity. However, serogroup B and C, ET37/ST-11 isolates both express similar virulence as assessed from colonization and invasiveness in a mouse model. Our results indicate that capsule switching events within the same clonal complex can arise frequently with no alteration in virulence. This justifies an enhanced system of surveillance by molecular typing of such isolates, particularly after serogroup-specific vaccination.
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Touqui L, Paya M, Thouron F, Guiyoule A, Zarantonelli ML, Leduc D, Wu Y, Taha MK, Alonso JM. Neisseria meningitidispili induce type-IIA phospholipase A2expression in alveolar macrophages. FEBS Lett 2005; 579:4923-7. [PMID: 16115633 DOI: 10.1016/j.febslet.2005.06.067] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2005] [Revised: 06/14/2005] [Accepted: 06/15/2005] [Indexed: 11/20/2022]
Abstract
Induction of type-IIA secreted phospholipase A2 (sPLA2-IIA) expression by bacterial components other than lipopolysaccharide has not been previously investigated. Here, we show that exposure of alveolar macrophages (AM) to Neisseria meningitidis or its lipooligosaccharide (LOS) induced sPLA2-IIA synthesis. However, N. meningitidis mutant devoid of LOS did not abolish this effect. In addition, a pili-defective mutant exhibited significantly lower capacity to stimulate sPLA2-IIA synthesis than the wild-type strain. Moreover, pili isolated from a LOS-defective strain induced sPLA2-IIA expression and nuclear factor kappa B (NF-kappaB) activation. These data suggest that pili are potent inducers of sPLA2-IIA expression by AM, through a NF-kappaB-dependent process.
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Taha MK, Alonso JM. Physiopathologie et pathogénie moléculaire des infections méningococciques invasives. Arch Pediatr 2005; 12:753-4. [PMID: 15904793 DOI: 10.1016/j.arcped.2005.04.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Njanpop-Lafourcade BM, Parent du Châtelet I, Sanou O, Alonso JM, Taha MK. The establishment of Neisseria meningitidis serogroup W135 of the clonal complex ET-37/ST-11 as an epidemic clone and the persistence of serogroup A isolates in Burkina Faso. Microbes Infect 2005; 7:645-9. [PMID: 15823512 DOI: 10.1016/j.micinf.2005.01.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2004] [Revised: 12/15/2004] [Accepted: 01/04/2005] [Indexed: 10/25/2022]
Abstract
We analyzed 48 invasive isolates of Neisseria meningitidis that were isolated from meningitis cases in Burkina Faso (April 2002 to April 2003). Thirty-nine of these isolates had the phenotype (serogroup:serotype:serosubtype) W135:2a:P1.5,2, eight isolates were A:4:P1.9 and one isolate was nongroupable:nonserotypable:nonserosubtypable. Genotyping of meningococcal isolates showed that W135 isolates belonged to the sequence type (ST)-11. The nongroupable isolate was of genogroup W135 and belonged to ST-192. Isolates of serogroup A belonged to ST-2859 (a member of the subgroup III/ST-5 clonal complex). W135 (ST-11) isolates involved in meningitis outbreaks in Burkina Faso differed from those involved in the Hajj-2000 associated outbreak by their pulsed-field gel electrophoresis profile. These data confirm the changing epidemiology of meningococcal infection in Burkina Faso with the establishment and expansion of serogroup W135 N. meningitidis strains of the ET-37/ST-11 clonal complex, as well as the emergence of a new clone within the subgroup III/ST-5 clonal complex.
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Holst J, Feiring B, Naess LM, Norheim G, Kristiansen P, Høiby EA, Bryn K, Oster P, Costantino P, Taha MK, Alonso JM, Caugant DA, Wedege E, Aaberge IS, Rappuoli R, Rosenqvist E. The concept of ?tailor-made?, protein-based, outer membrane vesicle vaccines against meningococcal disease. Vaccine 2005; 23:2202-5. [PMID: 15755595 DOI: 10.1016/j.vaccine.2005.01.058] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Protein-based, outer membrane vesicle (OMV) vaccines have previously proven to be efficacious against serogroup B meningococcal disease in Norway and Cuba. Currently, a public health intervention is going on in order to control a serogroup B epidemic in New Zealand. The scale-up and standardization of vaccine production required for controlling the New Zealand epidemic has allowed the establishment of large-scale GMP manufacturing for OMV vaccines. The outcome of this will be licensing of the vaccine in New Zealand and possibly other countries. The availability of licensed OMV vaccines raises the question of whether such vaccines may provide the opportunity to control other outbreaks and epidemics. For instance, such a vaccine could control a localised outbreak of group B meningococci in Normandy, France. "Tailor-made" vaccines, focusing on the sub-capsular antigens may also be considered for use in sub-Saharan Africa for the prevention of the recurrent outbreaks by serogroups A and W135 meningococci. This assumption is based on the epidemiological observation that meningococcal outbreaks in Africa are clonal and are strikingly stable regarding their phenotypic characteristics.
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173
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Faye A, Mariani-Kurkjian P, Taha MK, Louzeau C, Bingen E, Bourrillon A. Aspects cliniques et évolutifs des infections à méningocoque W135 chez l'enfant : à propos de cinq observations. Arch Pediatr 2005; 12:291-4. [PMID: 15734127 DOI: 10.1016/j.arcped.2004.11.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2003] [Accepted: 11/12/2004] [Indexed: 11/28/2022]
Abstract
Meningococcal disease due to Neisseria meningitidis of serogroup W135 (N. meningitidis W135) is increasing in France. Clinical and outcome data concerning these infections in children are scarce. We report five cases of children hospitalized between June 2000 and December 2002 for N. meningitidis W135 infection. Extra-meningeal septic and/or non-septic complications were frequent and a prolonged post meningococcal inflammatory syndrome was reported. In N. meningitidis W135 infections a careful clinical evaluation of potential extra-meningeal complications and a long term follow up of children are needed.
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174
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Taha MK, Alonso JM, Cafferkey M, Caugant DA, Clarke SC, Diggle MA, Fox A, Frosch M, Gray SJ, Guiver M, Heuberger S, Kalmusova J, Kesanopoulos K, Klem AM, Kriz P, Marsh J, Mölling P, Murphy K, Olcén P, Sanou O, Tzanakaki G, Vogel U. Interlaboratory comparison of PCR-based identification and genogrouping of Neisseria meningitidis. J Clin Microbiol 2005; 43:144-9. [PMID: 15634963 PMCID: PMC540131 DOI: 10.1128/jcm.43.1.144-149.2005] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Twenty clinical samples (18 cerebrospinal fluid samples and 2 articular fluid samples) were sent to 11 meningococcus reference centers located in 11 different countries. Ten of these laboratories are participating in the EU-MenNet program (a European Union-funded program) and are members of the European Monitoring Group on Meningococci. The remaining laboratory was located in Burkina Faso. Neisseria meningitidis was sought by detecting several meningococcus-specific genes (crgA, ctrA, 16S rRNA, and porA). The PCR-based nonculture method for the detection of N. meningitidis gave similar results between participants with a mean sensitivity and specificity of 89.7 and 92.7%, respectively. Most of the laboratories also performed genogrouping assays (siaD and mynB/sacC). The performance of genogrouping was more variable between laboratories, with a mean sensitivity of 72.7%. Genogroup B gave the best correlation between participants, as all laboratories routinely perform this PCR. The results for genogroups A and W135 were less similar between the eight participating laboratories that performed these PCRs.
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175
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Taha MK, Olcén P. Molecular genetic methods in diagnosis and direct characterization of acute bacterial central nervous system infections. APMIS 2005; 112:753-70. [PMID: 15688522 DOI: 10.1111/j.1600-0463.2004.apm11211-1204.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Acute bacterial infection of the central nervous system requires rapid and adequate management. Etiological diagnosis is hence crucial. Moreover, the epidemic threat of certain bacteria necessitates a reliable characterization of the involved bacterial strains to follow the spread of epidemic strains. Conventional identification and characterization of etiological agents are basically based on culture and identification of bacterial markers most frequently by serological assays. Molecular identification and characterization of bacteria have been employed. They provide more reliable analysis of bacterial isolates. Molecular methods for non-culture diagnosis of bacterial infections have recently been developed. In many cases, the molecular assays have decreased the identification time of positive cultures and rescued detection of pathogens in culture-negative clinical samples.
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