Estimates of the reproductive numbers and demographic reconstruction of outbreak associated with C:P1.5-1,10-8:F3-6:ST-11(cc11) Neisseria meningitidis strains.

BACKGROUND: Neisseria meningitidis can cause sporadic cases and outbreaks of invasive disease, including meningitis and sepsis. The meningococcal serogroup C (MenC) is the second most common serogroup in Italy after MenB. In this study we have estimated the reproductive numbers and the demographic reconstruction on the genomes of invasive N. meningitidis C:P1.5-1,10-8:F3-6:ST-11(cc11) strains isolated in Italy in 2012 - 2017, a period that includes the outbreak in Tuscany. METHODS: The genomes of N. meningitidis were sequenced using the Illumina MiSeq platform, through the whole genome sequencing (WGS) method and were analyzed by the core genome MLST (cgMLST) approach, using the BIGSdb Genome Comparator tool implemented on the PubMLST website. A Bayesian method was applied to study population dynamics across the entire N. meningitidis dataset. The basic reproduction number R0, which indicates the average number of secondary cases generated by a single primary case, was calculated using a Bayesian method, on the dataset and on the two subsets. The effective reproduction number R(t), defined as the average number of secondary cases per infectious case in a population, made up of susceptible and non-susceptible hosts was studied on the Tuscany dataset, with a Bayesian method. RESULTS: An increase in the effective number of the N. meningitidis infections was observed between 2013 and 2016. The estimated R0 parameter was 1.31 (95% HPD: 1.03 - 1.64), 1.22 (95% HPD: 0.90 - 1.64) and 1.4 (95% HPD: 0.91 - 1.9) for the entire dataset, first and second subset, respectively. The BDSKY estimated an initial R(t) of about 2.0 (95% HPD: 0.04 - 5.0), which showed a growing trend at the end of 2014, reaching an average value of 3.22 in 2015, and then declining below 1 from the year 2016. CONCLUSION: Monitoring the effective reproduction number can help to inform future vaccination strategies. The increase in the reproductive number for the Tuscany dataset, was consistent with the amplification event that led to the Tuscany outbreak. Subsequently, the intervention that led to the decline of the cases was followed, suggesting a high effectiveness of the vaccination campaign.

Development and pre-clinical evaluation of a synthetic oligosaccharide-protein conjugate vaccine against Neisseria meningitidis serogroup C.

Significant improvement has been made in the development of vaccines against Neisseria meningitidis infections since the introduction of polysaccharide-protein conjugate vaccines. Conventional bacterial capsular polysaccharide (PS) based conjugate vaccines require unique and expensive manufacturing facilities, complex production processes and extensive quality testing. Synthetic oligosaccharide (OS) based approach is one of the novel technologies that is being developed to simplify production of conjugate vaccines. OSs can be chemically synthesized to a desired length long enough to represent the antigenic epitopes which often present as a homogenous mixture. We prepared OSs corresponding to tetramer and octamer of N. meningitidis serogroup C (MenC) PS by organic synthesis. The MenC tetramer and octamer were further conjugated with tetanus toxoid to produce respective monovalent conjugates having the desired physico-chemical characteristics. The conjugates were evaluated in a mouse model for immunogenicity and compared with a licensed PS conjugate vaccine. Synthetic conjugates could induce anti-MenC PS IgG as well as serum bactericidal titers at levels comparable to those elicited by the licensed vaccine. The increase in length of synthetic oligomers from tetramer to octamer did not appear to increase immunogenicity. The results establish the pre-clinical proof of concept for a synthetic MenC oligosaccharide conjugate vaccine candidate.

cgMLST characterisation of invasive Neisseria meningitidis serogroup C and W strains associated with increasing disease incidence in the Republic of Ireland.

INTRODUCTION AND AIMS: Since 2013 MenC and MenW disease incidence and associated mortality rates have increased in the Republic of Ireland. From 2002/2003 to 2012/2013, the average annual MenC incidence was 0.08/100,000, which increased to 0.34/100,000 during 2013/2014 to 2017/18, peaking in 2016/17 (0.72/100,000) with an associated case fatality rate (CFR) of 14.7%. MenW disease incidence has increased each year from 0.02/100,000 in 2013/2014, to 0.29/100,000 in 2017/18, with an associated CFR of 28.6%. We aimed to characterise and relate recent MenC isolates to the previously prevalent MenC:cc11 ET-15 clones, and also characterise and relate recent MenW isolates to the novel 'Hajj' clones. METHODS: Using WGS we characterised invasive (n = 74, 1997/98 to 2016/17) and carried (n = 16, 2016/17) MenC isolates, and invasive (n = 18, 2010/11 to 2016/17) and carried (n = 15, 2016/17) MenW isolates. Genomes were assembled using VelvethOptimiser and stored on the PubMLST Neisseria Bacterial Isolate Genome Sequence Database. Isolates were compared using the cgMLST approach. RESULTS: Most MenC and MenW isolates identified were cc11. A single MenC:cc11 sub-lineage contained the majority (68%, n = 19/28) of recent MenC:cc11 disease isolates and all carried MenC:cc11 isolates, which were interspersed and distinct from the historically significant ET-15 clones. MenW:cc11 study isolates clustered among international examples of both the original UK 2009 MenW:cc11, and novel 2013 MenW:cc11clones. CONCLUSIONS: We have shown that the majority of recent MenC disease incidence was caused by strain types distinct from the MenC:cc11 ET-15 clone of the late 1990s, which still circulate but have caused only sporadic disease in recent years. We have identified that the same aggressive MenW clone now established in several other European countries, is endemic in the RoI and responsible for the recent MenW incidence increases. This data informed the National immunisation Advisory Committee, who are currently deliberating a vaccine policy change to protect teenagers.

Virulence Traits of a Serogroup C Meningococcus and Isogenic cssA Mutant, Defective in Surface-Exposed Sialic Acid, in a Murine Model of Meningitis.

In serogroup C Neisseria meningitidis, the cssA (siaA) gene codes for an UDP-N-acetylglucosamine 2-epimerase that catalyzes the conversion of UDP-N-acetyl-α-d-glucosamine into N-acetyl-d-mannosamine and UDP in the first step in sialic acid biosynthesis. This enzyme is required for the biosynthesis of the (α2→9)-linked polysialic acid capsule and for lipooligosaccharide (LOS) sialylation. In this study, we have used a reference serogroup C meningococcal strain and an isogenic cssA knockout mutant to investigate the pathogenetic role of surface-exposed sialic acids in a model of meningitis based on intracisternal inoculation of BALB/c mice. Results confirmed the key role of surface-exposed sialic acids in meningococcal pathogenesis. The 50% lethal dose (LD50) of the wild-type strain 93/4286 was about four orders of magnitude lower than that of the cssA mutant. Compared to the wild-type strain, the ability of this mutant to replicate in brain and spread systemically was severely impaired. Evaluation of brain damage evidenced a significant reduction in cerebral hemorrhages in mice infected with the mutant in comparison with the levels in those challenged with the wild-type strain. Histological analysis showed the typical features of bacterial meningitis, including inflammatory cells in the subarachnoid, perivascular, and ventricular spaces especially in animals infected with the wild type. Noticeably, 80% of mice infected with the wild-type strain presented with massive bacterial localization and accompanying inflammatory infiltrate in the corpus callosum, indicating high tropism of meningococci exposing sialic acids toward this brain structure and a specific involvement of the corpus callosum in the mouse model of meningococcal meningitis.

Tracking a serial killer: Integrating phylogenetic relationships, epidemiology, and geography for two invasive meningococcal disease outbreaks.

BACKGROUND: While overall rates of meningococcal disease have been declining in the United States for the past several decades, New York City (NYC) has experienced two serogroup C meningococcal disease outbreaks in 2005-2006 and in 2010-2013. The outbreaks were centered within drug use and sexual networks, were difficult to control, and required vaccine campaigns. METHODS: Whole Genome Sequencing (WGS) was used to analyze preserved meningococcal isolates collected before and during the two outbreaks. We integrated and analyzed epidemiologic, geographic, and genomic data to better understand transmission networks among patients. Betweenness centrality was used as a metric to understand the most important geographic nodes in the transmission networks. Comparative genomics was used to identify genes associated with the outbreaks. RESULTS: Neisseria meningitidis serogroup C (ST11/ET-37) was responsible for both outbreaks with each outbreak having distinct phylogenetic clusters. WGS did identify some misclassifications of isolates that were more distant from the outbreak strains, as well as those that should have been included based on high genomic similarity. Genomes for the second outbreak were more similar than the first and no polymorphism was found to either be unique or specific to either outbreak lineage. Betweenness centrality as applied to transmission networks based on phylogenetic analysis demonstrated that the outbreaks were transmitted within focal communities in NYC with few transmission events to other locations. CONCLUSIONS: Neisseria meningitidis is an ever changing pathogen and comparative genomic analyses can help elucidate how it spreads geographically to facilitate targeted interventions to interrupt transmission.

El declive de la incidencia de enfermedad meningocócica en Barcelona entre 1988 y 2015: la influencia de la vacunación frente al serogrupo C / The decline of the incidence of meningococcal disease in Barcelona between 1988 and 2015: the influence of the vaccine against serogroup C

Introducción y objetivo: El objetivo es conocer la evolución de la enfermedad meningocócica en la ciudad de Barcelona entre 1988 y 2015 y evaluar el impacto de la vacuna contra el serogrupo C. Materiales y métodos: Se analizó la evolución de casos de enfermedad meningocócica y por serogrupo a partir del registro de enfermedades de declaración obligatoria. Se comparó la incidencia de todos los serogrupos antes y después de la introducción de la vacunación contra el serogrupo C en el año 2000. Se analizó la cobertura vacunal entre los casos, el serogrupo entre casos vacunados y la tasa de mortalidad y letalidad. Resultados: La enfermedad meningocócica ha pasado de una incidencia en menores de un año de 63,09 casos por 100.000 en 1997-2000 a 15,44 en 2001-2015. Todos los serogrupos han disminuido su incidencia tras la implementación vacunal, especialmente en niños de uno a 4 años para el C. A partir del 2000 la cobertura vacunal en los casos por este serogrupo era del 7,6% y en los afectos por el B era del 35,0% (p<0,01). De los vacunados, el 66,4% de los casos fue serogrupo B y un 5,2% fue C (p<0,01). La tasa global de letalidad y de mortalidad fue del 7,7% y del 0,19/100.000 respectivamente, sin cambios significativos en el tiempo en cuanto a la letalidad. Conclusiones: La incidencia por serogrupo C y también por B ha disminuido tras la vacunación sistemática contra el serogrupo C. La vacunación contra el serogrupo B podría reducir aún más esta grave enfermedad con una letalidad importante que no ha disminuido en todo el periodo

Introduction and objective: The purpose of this study was to describe the evolution of meningococcal disease (MD) in the city of Barcelona between 1988 and 2015 and to assess the impact of the vaccine against serogroup C. Materials and methodology: The evolution of MD and by serogroup was analysed using the information included in the mandatory notification diseases registry. Incidences of all serogroups between the periods of before and after the implementation of the serogroup C vaccine in 2000 were compared. Vaccination coverage among cases, serogroup among vaccinated cases and mortality and case fatality rates were analysed. Results: MD has evolved from an incidence rate in children aged under 1 of 63.09 cases per 100,000 in 1997-2000 to 15.44 per 100,000 in 2001-2015. All MD serogroups incidences decreased after the implementation of the vaccine, especially for serogroup C among children aged between 1 and 4. Since 2000 vaccine coverage in MD cases by this serogroup was 7.6% while in those affected by serogroup B it was 35.0% (p<.01). Among those vaccinated, 66.4% of cases were serogroup B and 5.2% were C (p<.01). Mortality and case fatality rates were 7.7% and 0.19/100,000 respectively, without significant changes in time regarding case fatality. Conclusions: Incidence caused by serogroups B and C has decreased after the systematic vaccination against serogroup C. Vaccination against serogroup B could further reduce the impact of this lethal disease which has not decreased during this period

Meningococcus serogroup C clonal complex ST-10217 outbreak in Zamfara State, Northern Nigeria.

After the successful roll out of MenAfriVac, Nigeria has experienced sequential meningitis outbreaks attributed to meningococcus serogroup C (NmC). Zamfara State in North-western Nigeria recently was at the epicentre of the largest NmC outbreak in the 21st Century with 7,140 suspected meningitis cases and 553 deaths reported between December 2016 and May 2017. The overall attack rate was 155 per 100,000 population and children 5-14 years accounted for 47% (3,369/7,140) of suspected cases. The case fatality rate (CFR) among children 5-9 years was 10%, double that reported among adults ≥ 30 years (5%). NmC and pneumococcus accounted for 94% (172/184) and 5% (9/184) of the laboratory-confirmed cases, respectively. The sequenced NmC belonged to the ST-10217 clonal complex (CC). All serotyped pneumococci were PCV10 serotypes. The emergence of NmC ST-10217 CC outbreaks threatens the public health gains made by MenAfriVac, which calls for an urgent strategic action against meningitis outbreaks.

Neisseria meningitidis serogroup C sepsis and septic arthritis in an HIV-positive man.

A patient with well-controlled HIV-1 infection presented with fever and rigors, a widespread maculopapular rash, and severe generalised arthralgia. Sepsis of unknown aetiology was diagnosed, and treatment with broad-spectrum antimicrobials commenced. Following initial clinical improvement, a right knee septic arthritis developed. Microscopy and culture of the joint aspirate were negative for organisms but 16S rDNA PCR identified Neisseria meningitidis DNA, subsequently verified as capsular genogroup C, thus confirming a diagnosis of disseminated meningococcal sepsis with secondary septic arthritis.

Vacuna conjugada frente al meningococo C: impacto del programa de vacunación y efectividad a largo plazo en Navarra, 2000-2014 / Meningococcal C conjugate vaccine: Impact of a vaccination program and long-term effectiveness in Navarra, Spain, 2000-2014

INTRODUCCIÓN: Desde la introducción en el calendario de vacunación infantil de la vacuna conjugada frente al meningococo C (Men CC) en el año 2000, se ha modificado la pauta y se han realizado campañas de vacunación en cohortes de nacimiento específicas. El objetivo de este estudio es estimar el impacto y la efectividad de esta vacuna en Navarra hasta 2014. MÉTODOS: El impacto se evaluó comparando incidencia, mortalidad y letalidad de enfermedad por meningococo C en los periodos anterior (1995-1999) y posterior (2001-2014) a la vacunación. La efectividad se estimó mediante el método de cribado (Farrington) y el de cohorte indirecta (Broome). Los casos se recogieron del sistema de vigilancia de la enfermedad meningocócica en Navarra. RESULTADOS: En el periodo 1995-1999 la incidencia media anual de enfermedad por meningococo C era de 1,32 por 100.000 habitantes, y de 7,18 por 100.000 en menores de 15 años. El descenso de la incidencia fue contundente en los grupos de edad diana de la vacuna desde su introducción y ha sido progresivo en la población total. Entre 2011 y 2014 no se registraron casos por meningococo C. La efectividad de la vacuna para prevenir casos por este serogrupo se estimó entre el 96% (método de cribado) y el 99% (método de cohorte indirecta). CONCLUSIÓN: El programa de vacunación con Men CC ha logrado con éxito disminuir la incidencia de la enfermedad por serogrupo C en Navarra, y los ajustes en la pauta vacunal han conseguido mantener una elevada efectividad vacunal en el tiempo

BACKGROUND: Since 2000, when the meningococcal serogroup C conjugate vaccine (Men CC) was introduced in the childhood immunization schedule in Spain, several changes in the schedule and catch-up campaigns have been performed. We aim to estimate the impact and effectiveness of this vaccine in Navarra up to 2014. METHODS: The impact of the vaccination program was analysed by comparing incidence, mortality and lethality rates of disease before (1995-1999) and after (2004-2014) the introduction of the Men CC. Vaccine effectiveness was estimated using the screening method (Farrington) and the indirect cohort method (Broome). Data on cases were obtained from the active surveillance of meningococcal disease. RESULTS: During 1995-1999 the mean annual incidence of meningococcal C disease was 1.32 per 100,000, and 7.18 per 100,000 in children younger than 15 years. The fall of meningococcal C disease incidence was significant in cohorts targeted for vaccination from the beginning and progressive in the general population. No cases were reported between 2011 and 2014. The estimated vaccine effectiveness was 96% by the screening method, and 99% by the indirect cohort method. CONCLUSION: The Men CC vaccination program has been successful in decreasing the incidence rate of serogroup C meningococcal disease in Navarra, and schedule changes have maintained high vaccine effectiveness throughout the study period

Evolutionary Events Associated with an Outbreak of Meningococcal Disease in Men Who Have Sex with Men.

Meningococci spread via respiratory droplets, whereas the closely related gonococci are transmitted sexually. Several outbreaks of invasive meningococcal disease have been reported in Europe and the United States among men who have sex with men (MSM). We recently identified an outbreak of serogroup C meningococcal disease among MSM in Germany and France. In this study, genomic and proteomic techniques were used to analyze the outbreak isolates. In addition, genetically identical urethritis isolates were recovered from France and Germany and included in the analysis. Genome sequencing revealed that the isolates from the outbreak among MSM and from urethritis cases belonged to a clade within clonal complex 11. Proteome analysis showed they expressed nitrite reductase, enabling anaerobic growth as previously described for gonococci. Invasive isolates from MSM, but not urethritis isolates, further expressed functional human factor H binding protein associated with enhanced survival in a newly developed transgenic mouse model expressing human factor H, a complement regulatory protein. In conclusion, our data suggest that urethritis and outbreak isolates followed a joint adaptation route including adaption to the urogenital tract.

Genome-based study of a spatio-temporal cluster of invasive meningococcal disease due to Neisseria meningitidis serogroup C, clonal complex 11.

OBJECTIVES: To describe a spatio-temporal cluster of invasive meningococcal disease (IMD) due to serogroup C meningococci, occurred in a restricted area of Tuscany between January and October 2015, and the results of whole genome sequencing (WGS). METHODS: Surveillance activities and public health measures were implemented in the Region. Bacterial isolates from IMD cases were characterized by the National Reference Laboratory of the Istituto Superiore di Sanità (ISS), and WGS was performed on available strains. The kSNP software was used to identify core genome SNPs. RESULTS: Overall, 28 IMD cases due to meningococcus C were identified up to 31st October, 2015. Of them, 26 were due to meningococcus C:P1.5-1,10-8: F3-6:ST-11 (cc11) and 2 to C:P1.5-1,10-8: F3-6:ST-2780 (cc11). WGS of 13 meningococci isolated during the outbreak occurred in Tuscany in 2015 showed higher similarity when compared with those of 47 C: P1.5-1,10-8: F3-6:ST-11 (cc11) invasive strains from sporadic cases previously detected in Italy. CONCLUSIONS: A highly aggressive meningococcal C strain was involved in the cluster of severe IMD occurred in Tuscany, a Region with high vaccine coverage among children. Whether this was due to low herd immunity related to the short duration of vaccine protection needs further investigation.

Lipooligosaccharide Structures of Invasive and Carrier Isolates of Neisseria meningitidis Are Correlated with Pathogenicity and Carriage.

The degree of phosphorylation and phosphoethanolaminylation of lipid A on neisserial lipooligosaccharide (LOS), a major cell-surface antigen, can be correlated with inflammatory potential and the ability to induce immune tolerance in vitro. On the oligosaccharide of the LOS, the presence of phosphoethanolamine and sialic acid substituents can be correlated with in vitro serum resistance. In this study, we analyzed the structure of the LOS from 40 invasive isolates and 25 isolates from carriers of Neisseria meningitidis without disease. Invasive strains were classified as groups 1-3 that caused meningitis, septicemia without meningitis, and septicemia with meningitis, respectively. Intact LOS was analyzed by high resolution matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Prominent peaks for lipid A fragment ions with three phosphates and one phosphoethanolamine were detected in all LOS analyzed. LOS from groups 2 and 3 had less abundant ions for highly phosphorylated lipid A forms and induced less TNF-α in THP-1 monocytic cells compared with LOS from group 1. Lipid A from all invasive strains was hexaacylated, whereas lipid A of 6/25 carrier strains was pentaacylated. There were fewer O-acetyl groups and more phosphoethanolamine and sialic acid substitutions on the oligosaccharide from invasive compared with carrier isolates. Bioinformatic and genomic analysis of LOS biosynthetic genes indicated significant skewing to specific alleles, dependent on the disease outcome. Our results suggest that variable LOS structures have multifaceted effects on homeostatic innate immune responses that have critical impact on the pathophysiology of meningococcal infections.

Community-Based Outbreak of Neisseria meningitidis Serogroup C Infection in Men who Have Sex with Men, New York City, New York, USA, 2010-2013.

In September 2012, the New York City Department of Health and Mental Hygiene identified an outbreak of Neisseria meningitidis serogroup C invasive meningococcal disease among men who have sex with men (MSM). Twenty-two case-patients and 7 deaths were identified during August 2010-February 2013. During this period, 7 cases in non-MSM were diagnosed. The slow-moving outbreak was linked to the use of websites and mobile phone applications that connect men with male sexual partners, which complicated the epidemiologic investigation and prevention efforts. We describe the outbreak and steps taken to interrupt transmission, including an innovative and wide-ranging outreach campaign that involved direct, internet-based, and media-based communications; free vaccination events; and engagement of community and government partners. We conclude by discussing the challenges of managing an outbreak affecting a discrete community of MSM and the benefits of using social networking technology to reach this at-risk population.

Muerte súbita por sepsis meningocócica: diagnóstico post mórtem / Sudden death from meningococcal sepsis: postmortem diagnosis

La presentación más común de la enfermedad meningocócica es la meningitis, con una tasa de incidencia de 0,92 por 100.000 habitantes y una letalidad del 40,3% en España. Un cuadro meníngeo puede cursar con síntomas inespecíficos como la cefalea, entre otros, de tal forma que en ocasiones progresa rápidamente en cuestión de horas y provoca la muerte del paciente antes de haber recibido una atención médica adecuada. Además de la meningitis clásica, el meningococo produce una enfermedad sistémica que incluye la sepsis meningocócica y la coagulopatía intravascular diseminada. En pacientes con sepsis meningocócica se ha descrito el síndrome de Waterhouse-Friderichsen, que se caracteriza por hemorragia suprarrenal bilateral, coagulación intravascular diseminada e hígado de shock, y que produce una bacteriemia grave. Esta combinación provoca unshock fulminante y, si no se trata, puede producir muerte súbita. Presentamos el caso de una paciente con odinofagia, fiebre, vómitos y deposiciones diarreicas de 24 horas de evolución, que a pesar de recibir asistencia médica ambulatoria y hospitalaria fallece como consecuencia de una sepsis fulminante por Neisseria meningitidis y síndrome de Waterhouse-Friderichsen no diagnosticado clínicamente (AU)

The most common presentation of meningococcal disease is meningitis, with an incidence rate of 0.92 per 100,000 inhabitants and a mortality rate of 40.3% in Spain. Meningeal disease may present with nonspecific symptoms such as headache, among others, sometimes progressing rapidly to a fatal outcome before the patient receives adequate medical care. Besides classical meningitis, Neisseria meningitis produces a systemic disease that includes meningococcal sepsis and disseminated intravascular coagulopathy. In patients with meningococcal sepsis the Waterhouse-Friderichsen syndrome is described, which is characterized by bilateral adrenal hemorrhage, intravascular coagulation and shock liver, producing a severe bacteremia. This combination causes a fulminant shock and, if untreated, it may cause sudden death. We report the case of a female patient with sore throat, fever, vomiting and diarrhea of 24 hours of evolution. Despite receiving inpatient and outpatient medical care, she died as a result of N. meningitidis fulminant sepsis and clinically undiagnosed Waterhouse-Friderichsen syndrome (AU)

Elevada letalidad por enfermedad meningocócica C en adultos en la provincia de Sevilla (2008-2012) / High mortality of meningococcal group C disease in adults in the Seville province, Spain (2008-2012)

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Replacement of Neisseria meningitidis C cc11/ET-15 variant by a cc103 hypervirulent clone, Brazil 2005-2011.

Outbreaks caused by serogroup C meningococci in the northeast region of Brazil from 2005 to 2011 were associated to the emergence of variant ET-15 of cc11, which has been replaced by cc103 from 2006 to date. The increase of cc103 should be closely monitored to prevent the spread of this clone to neighbouring regions.

[Paediatric meningococcal meningitis in France: ACTIV/GPIP network results]. / Méningites à méningocoques de l'enfant en France: résultats de l'observatoire ACTIV/GPIP.

BACKGROUND: The GPIP/ACTIV (Groupe de Pathologie Infectieuse Pédiatrique and Association Clinique et Thérapeutique Infantile du Val de Marne) set up an active surveillance network to analyze the epidemiological, clinical and biological features of meningococcal meningitis. METHODS: French pediatric wards working with 166 microbiology laboratories enrolled all children (0-18 years old) with bacterial meningitis. Risk factors, signs and symptoms, vaccination status, cerebrospinal fluid analysis, treatments and case fatality rate were recorded. RESULTS: Since 2001, 1661 meningococcal meningitis were reported among 3769 (44.1%) bacterial meningitis. Mean age was 4.4- year- old (± 4.8, median 2.5) and 2/3 cases occurred in children under 5- year- old (68.8%). Serogroup B (61.3%) is preponderant following by serogroup C (27.0%). 27.5% of children had received an antibiotic treatment 24 hours before lumbar puncture. A shock is reported in 31.0% of cases. No cases of meningococcal meningitis C has been reported in children vaccinated with a conjugate vaccine. Two children vaccinated with MenBvac(®) vaccine had a meningitis B14:P1.7,16. Global case fatality rate was 6.5% but was higher (9.2%) for serogroup C than for serogroup B (5.9%) (p=0.02). CONCLUSION: This is among the largest series of microbiologically documented meningococcal meningitis to date (1661 cases). In France, meningococcal is responsible for approximately 50 % of meningitis. Effective meningococcal serogroup B vaccine and serogroup C vaccination recommendation could control the burden of meningococcal meningitis.

Caracterización fenotípica y molecular de neisseria meningitidis del serogrupo C asociada con un brote en Bahia, Brasil / Phenotypic and molecular characterization of serogroup C Neisseria meningitidis associated with an outbreak in Bahia, Brazil

Objetivo Caracterizar las cepas de Neisseria meningitidis (Nm) aisladas de cinco pacientes con Enfermedad Meningocócica (EM) asociada a un brote epidémico en Trancoso - BA, que ocurrió en octubre del 2009, luego de una fiesta en zona rural y en la que participaron 1000 jóvenes .Todos los casos fueron secundarios al caso primario a excepción de un paciente varón de 39 años. Materiales y métodos El Servicio de Vigilancia Epidemiológica del Estado de Bahia realizó la investigación epidemiológica y las cepas de Nm se caracterizaron en el Laboratorio Nacional de Referencia para Meningitis, Instituto Adolfo Lutz - São Paulo mediante métodos convencionales (sero - subtipificación y prueba de sensibilidad a los antimicrobianos) y métodos moleculares (electroforesis en gel de campo pulsado- PFGE y Multilocus Sequence Typing - MLST).Resultados La PFGE mostró dos perfiles de restricción estrechamente relacionados designados como PFGE tipos A y A1 con 92% de relación entre sí. Ambos tipos fueron clasificados como ST-3780 mediante MLST, y pertenecientes al complejo clonal ST-103. Todos los aislados mostraron el fenotipo C: 23: P1.5 y eran susceptibles a todos los antibióticos testados. Conclusiones Este es el primer brote de EM reportado asociado a cepas de Nm serogrupo C del complejo clonal ST-103 y relacionado con el consumo de drogas en Brasil (AU)

Objective To characterize meningococcal strains isolated from five cases of meningococcal disease (MD) associated with an outbreak in Trancoso - BA, occurred in October 2009. All cases, with the exception of a 39-year-old male, attended a dance party with approximately 1000 youngsters in a rural site. Materials and methods The epidemiological investigation was conducted by the Epidemiological Surveillance Service of Bahia State. Meningococcal strains were characterized at Adolfo Lutz Institute, the Brazilian National Reference Laboratory for Bacterial Meningitis by conventional techniques (serotype, serosubtype and antimicrobial susceptibility test) and by molecular methods (Pulsed-field gel electrophoresis - PFGE and Multilocus Sequence Typing - MLST).Results The PFGE showed 2 closely related restriction profiles, designated as PFGE types A and A1, having 92% relatedness to each other. MLST characterization showed both A and A1 clones were ST-3780, which belongs to the ST-103 complex. All isolates displayed the phenotype C:23:P1.5 and were susceptible to all antibiotics tested. Conclusions This is the first reported MD outbreak associated with serogroup C ST-103 complex in Brazil, as well as the party and illicit drug-use associated outbreak (AU)

Epidemiología de la enfermedad meningocócia en Cataluña antes y después de la vacunación frente al serogrupo C / Epidemiology of the meningococcal disease in Catalonia before and after vaccination against serogroup C

Fundamentos: La enfermedad meningocócica continúasiendo un grave problema de salud pública en todo el mundo.En Cataluña, tras implementar el programa de vacunación, hahabido un descenso importante de los casos producidos pormeningococo C.Métodos: Se analizaron los casos notificados de enfermedadmeningocócica entre 1997 y 2008 para determinar la evolucióndespués de la introducción de la vacuna conjugada en Cataluña.Resultados: La tasa de incidencia de casos por serogrupoC en menores de 6 años se redujo de 7,6 por 100000 personas/año en el período prevacunal (1997-2000) hasta 0,6 en elperíodo postvacunal (2001-2007). En los casos por serogrupoB, la reducción fue mucho menor, de 15.4 a 11.1. En los menoresde 20 años, la tasa de letalidad solo aumento en los casospor serogrupo B (3% en el período prevacunal y 7.4% en elpostvacunal).Entre 2000 y 2008, el subtipo P1.15 ha sido elmás frecuentemente identificado entre los casos por serogrupoB (31%), asociado principalmente al serotipo 4 (80%), y elsubtipo P1.5 (36%) asociado mayoritariamente al serotipo 2a(86%), en los casos por serogrupo C. Durante 2008, 5 casos deB:2a:P1.5, sin aparente relación entre sí fueron identificadosen una misma zona geográfica, con una letalidad de 80%.Conclusiones: Es necesario mantener una constante yexhaustiva vigilancia para conocer las cepas circulantes encada momento y detectar precozmente posibles cambios yrecombinaciones entre ellas(AU)

Backgrounds: Meningococcal disease remains a seriouspublic health problem worldwide. In Catalonia, afterimplementing the vaccination program, there has been asignificant decrease in cases caused by meningococcus C.Methods: Reported cases of meningococcal diseasebetween 1997 and 2008 were analyzed to determine theevolution after the introduction of a conjugated vaccine inCatalonia.Results: In <6 years, the incidence rate of serogroup C fellfrom 7.6 to 0.6 per 100,000 persons/year in the periods before(1997-2000) and after (2001-2007) the introduction of theconjugate vaccine. In serogroup B, the reduction was from15.4 to 11.1. In <20 years case-fatality-rate increased only inserogroup B (3% and 7.4%). Serosubtype P1.15was the mostfrequent in serogroup B (31%), mainly associated withserotype 4 (80%), and in serogroup C subtype P1.5 (36%),with serotype 2a (86%). During 2008, 5 apparently unrelatedcases of B:2a:P1.5 were identified in the same geographicarea, with a case-fatality-rate of 80%.Conclusions: Exhaustive surveillance of circulatingmeningococcal strains is essential(AU)

Absence of Neisseria meningitidis serogroup C-specific antibodies during the first year of life in the Netherlands: an age group at risk?

In The Netherlands, a single meningococcal serogroup C conjugate (MenCC) vaccination is administered to children at the age of 14 months. Here, we report the levels of MenC polysaccharide-specific antibodies in children at birth and at 3, 11, and 12 months of age and the presence of functional antibodies at 11 months of age, before infants receive their MenCC immunization. We observed a rapid decline in polysaccharide-specific antibodies after birth and no induction of naturally elicited polysaccharide-specific antibodies. Furthermore, at 11 months of age, no bactericidal antibodies are observed. These data indicate that these infants may be at risk in the period prior to MenCC immunization, if Neisseria meningitidis serogroup C starts to (re)circulate.