Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
PLoS One ; 15(12): e0243375, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33347452

RESUMEN

BACKGROUND: Neisseria meningitidis serogroup B remains a prominent cause of invasive meningococcal disease (IMD) in Brazil. Because two novel protein-based vaccines against serogroup B are available, the main purpose of this study was to provide data on the diversity and distribution of meningococcal vaccine antigen types circulating in Brazil. METHODOLOGY: Genetic lineages, vaccine antigen types, and allele types of antimicrobial-associated resistance genes based on whole-genome sequencing of a collection of 145 Neisseria meningitidis serogroup B invasive strains recovered in Brazil from 2016 to 2018 were collected. RESULTS: A total of 11 clonal complexes (ccs) were identified among the 145 isolates, four of which were predominant, namely, cc461, cc35, cc32, and cc213, accounting for 72.0% of isolates. The most prevalent fHbp peptides were 24 (subfamily A/variant 2), 47 (subfamily A/variant 3), 1 (subfamily B/variant 1) and 45 (subfamily A/variant 3), which were predominantly associated with cc35, cc461, cc32, and cc213, respectively. The NadA peptide was detected in only 26.2% of the isolates. The most frequent NadA peptide 1 was found almost exclusively in cc32. We found seven NHBA peptides that accounted for 74.5% of isolates, and the newly described peptide 1390 was the most prevalent peptide exclusively associated with cc461. Mutated penA alleles were detected in 56.5% of the isolates, whereas no rpoB and gyrA mutant alleles were found. CONCLUSION: During the study period, changes in the clonal structure of circulating strains were observed, without a predominance of a single hyperinvasive lineage, indicating that an epidemiologic shift has occurred that led to a diversity of vaccine antigen types in recent years in Brazil.


Asunto(s)
Variación Genética/genética , Infecciones Meningocócicas/genética , Vacunas Meningococicas/genética , Neisseria meningitidis Serogrupo B/genética , Adolescente , Adulto , Anciano , Brasil/epidemiología , Niño , Preescolar , Femenino , Genoma Bacteriano/genética , Genómica , Humanos , Inmunogenicidad Vacunal/genética , Inmunogenicidad Vacunal/inmunología , Lactante , Masculino , Infecciones Meningocócicas/epidemiología , Infecciones Meningocócicas/inmunología , Vacunas Meningococicas/inmunología , Vacunas Meningococicas/uso terapéutico , Persona de Mediana Edad , Tipificación de Secuencias Multilocus/métodos , Neisseria meningitidis Serogrupo B/patogenicidad , Serogrupo , Secuenciación Completa del Genoma , Adulto Joven
2.
PLoS One ; 15(7): e0234475, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32663215

RESUMEN

BACKGROUND: Neisseria meningitidis is a significant cause of morbidity and mortality worldwide. Meningococcal isolates have a highly dynamic population structure and can be phenotypically and genetically differentiated into serogroups and clonal complexes. The aim of this study was to describe the phenotypic and genotypic characteristics of invasive isolates recovered in Colombia from 2013 to 2016. METHODOLOGY: A total of 193 invasive isolates were analyzed. Phenotypic and genotypic characteristics were determined by serotyping, antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing. RESULTS: Based on the results, meningococcal serogroups C, B and Y were responsible for 47.9%, 41.7%, and 9.4% of cases, respectively, and the distribution of serogroups B and C changed over time. Fifteen clonal groups and 14 clonal complexes (cc) were identified by PFGE and genome sequencing. The main clonal group included serogroup B isolates with sequence type (ST)-9493 and its four single-locus variants, which has only been identified in Colombian isolates. The clonal population structure demonstrates that the isolates in this study mainly belong to four clonal complexes: ST-11 cc, ST-32 cc, ST-35 cc and ST-41/44 cc. Thirty-eight penA alleles were identified, but no correlation between MICs and specific sequences was observed. CONCLUSION: This study shows that most meningococcal isolates recovered from patients with invasive meningococcal disease in Colombia are strains associated with distinct globally disseminated hyperinvasive clones.


Asunto(s)
Infecciones Meningocócicas/epidemiología , Infecciones Meningocócicas/genética , Neisseria meningitidis/genética , Adolescente , Adulto , Técnicas de Tipificación Bacteriana/métodos , Niño , Preescolar , Colombia/epidemiología , Electroforesis en Gel de Campo Pulsado/métodos , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Neisseria meningitidis/aislamiento & purificación , Neisseria meningitidis/patogenicidad , Serogrupo , Serotipificación
3.
PLoS One ; 7(3): e33016, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22431994

RESUMEN

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.


Asunto(s)
Infecciones Meningocócicas/epidemiología , Infecciones Meningocócicas/microbiología , Neisseria meningitidis Serogrupo B/genética , Técnicas de Tipificación Bacteriana , Secuencia de Bases , Biodiversidad , Brasil/epidemiología , Genes Bacterianos/genética , Variación Genética , Geografía , Humanos , Funciones de Verosimilitud , Infecciones Meningocócicas/genética , Epidemiología Molecular , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Neisseria meningitidis Serogrupo B/clasificación , Neisseria meningitidis Serogrupo B/aislamiento & purificación , Filogenia , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA