Emergence of Neisseria meningitidis W South American sublineage strain variant in Brazil: disease and carriage.

Introduction. Invasive meningococcal disease is a major health problem, impacting morbidity and mortality worldwide. Exploratory genomics has revealed insights into adaptation, transmissibility and virulence to elucidate endemic, outbreaks or epidemics caused by Neisseria meningitidis serogroup W (MenW) strains.Gap Statement. Limited information on the genomics of Neisseria meningitis serogroup W ST11/cc11 is available from emerging countries, especially in contemporary isolates.Aim. To (i) describe the antigenic diversity and distribution of genetic lineages of N. meningitidis serogroup W circulating in Brazil; (ii) study the carriage prevalence of hypervirulent clones in adolescents students and (iii) analyse the potential risk factors for meningococcal carriage.Methodology. Using whole-genome sequencing, we analysed the genomic diversity of 92 invasive N. meningitidis serogroup W isolates circulating in Brazil from 2016 to 2019. A cross-sectional survey of meningococcal carriage was conducted in 2019, in the city of Florianópolis, Brazil, among a representative sample of 538 students.Results. A predominance (58.5 %, 41/82) of ST11/cc11 presenting PorB2-144, PorA VR1-5, VR2-2, FetA 1-1, and a novel fHbp peptide 1241 was found on invasive N. meningitidis W isolates, on the other hand, a high diversity of clonal complexes was found among carriage isolates. The overall carriage rate was 7.5 % (40/538). A total of 28 of 538 swab samples collected were culture positive for N. meningitidis, including four serogroup/genogroup B isolates (14.8 %;4/27), 1 serogroup/genogroup Y isolate (3.7 %;1/27), 22 (81.5 %; 22/27) non-groupable isolates. No MenW isolate was identified among carriages isolates.Conclusion. This report describes the emergence of the new MenW ST11/cc11 South America sublineage variant, named here, 2016 strain, carrying a novel fHbp peptide 1241, but its emergence, was not associated with an increased MenW carriage prevalence. Continuous surveillance is necessary to ascertain the role of this sublineage diversification and how its emergence can impact transmission.

Emergence of Neisseria meningitidis W South American sublineage strain variant in Brazil: disease and carriage

Introduction. Invasive meningococcal disease is a major health problem, impacting morbidity and mortality worldwide. Exploratory genomics has revealed insights into adaptation, transmissibility and virulence to elucidate endemic, outbreaks or epidemics caused by Neisseria meningitidis serogroup W (MenW) strains.Gap Statement. Limited information on the genomics of Neisseria meningitis serogroup W ST11/cc11 is available from emerging countries, especially in contemporary isolates.Aim. To (i) describe the antigenic diversity and distribution of genetic lineages of N. meningitidis serogroup W circulating in Brazil; (ii) study the carriage prevalence of hypervirulent clones in adolescents students and (iii) analyse the potential risk factors for meningococcal carriage.Methodology. Using whole-genome sequencing, we analysed the genomic diversity of 92 invasive N. meningitidis serogroup W isolates circulating in Brazil from 2016 to 2019. A cross-sectional survey of meningococcal carriage was conducted in 2019, in the city of Florianópolis, Brazil, among a representative sample of 538 students.Results. A predominance (58.5 %, 41/82) of ST11/cc11 presenting PorB2-144, PorA VR1-5, VR2-2, FetA 1-1, and a novel fHbp peptide 1241 was found on invasive N. meningitidis W isolates, on the other hand, a high diversity of clonal complexes was found among carriage isolates. The overall carriage rate was 7.5 % (40/538). A total of 28 of 538 swab samples collected were culture positive for N. meningitidis, including four serogroup/genogroup B isolates (14.8 %;4/27), 1 serogroup/genogroup Y isolate (3.7 %;1/27), 22 (81.5 %; 22/27) non-groupable isolates. No MenW isolate was identified among carriages isolates.Conclusion. This report describes the emergence of the new MenW ST11/cc11 South America sublineage variant, named here, 2016 strain, carrying a novel fHbp peptide 1241, but its emergence, was not associated with an increased MenW carriage prevalence. Continuous surveillance is necessary to ascertain the role of this sublineage diversification and how its emergence can impact transmission.

Prevalence, risk factors and molecular characteristics of meningococcal carriage among brazilian adolescents

BACKGROUND: In 2010, introduction of the meningococcal C conjugate vaccine in Brazil for children <2 years provided an immediate reduction in the incidence rates of disease among the age groups targeted for the vaccine, but no early impact was observed in unvaccinated age groups. Knowledge about meningococcal carriage is crucial for improving our understanding of the disease epidemiology and for designing effective vaccination programs. Taking in account the very limited published data currently available describing meningococcal carriage in Brazil, we performed a study to evaluate the prevalence of Neisseria meningitidis carriage among adolescent students. METHODS: A cross-sectional study was conducted in 2012 to assess the prevalence of meningococcal carriage among a representative sample of 1208 students 11­19 years of age in Campinas, Brazil. Genotypic and phenotypic characterization of isolated carriage strains and the effect of potential risk factors for carriage were also analyzed. Results: The overall carriage prevalence was 9.9% (95% confidence interval, 8.3­11.8%), with dominance of serogroup C (1.32%), followed by serogroups B (0.99%), E (0.74%), Y (0.49%) and W (0.25%). A lower level of education of the parents was independently associated with a higher risk of carriage. A high diversity of genotypes was found among carriage strains. CONCLUSIONS: The evidence gathered during this study provides estimates of carriage prevalence in Brazilian adolescents, showing an unusually high dominance of serogroup C. These results have important implications in future strategies to optimize the impact of the current meningococcal C vaccination program in Brazil

Carriage rate and effects of vaccination after outbreaks of serogroup C meningococcal disease, Brazil, 2010.

During 2010, outbreaks of serogroup C meningococcal (MenC) disease occurred in 2 oil refineries in São Paulo State, Brazil, leading to mass vaccination of employees at 1 refinery with a meningococcal polysaccharide A/C vaccine. A cross-sectional study was conducted to assess the prevalence of meningococci carriage among workers at both refineries and to investigate the effect of vaccination on and the risk factors for pharyngeal carriage of meningococci. Among the vaccinated and nonvaccinated workers, rates of overall meningococci carriage (21.4% and 21.6%, respectively) and of MenC carriage (6.3% and 4.9%, respectively) were similar. However, a MenC strain belonging to the sequence type103 complex predominated and was responsible for the increased incidence of meningococcal disease in Brazil. A low education level was associated with higher risk of meningococci carriage. Polysaccharide vaccination did not affect carriage or interrupt transmission of the epidemic strain. These findings will help inform future vaccination strategies.

Clonal distribution of invasive Neisseria meningitidis serogroup C strains circulating from 1976 to 2005 in greater Sao Paulo, Brazil.

Meningococcal disease is characterized by cyclic fluctuations in incidence, serogroup distribution, and antigenic profiles. In greater São Paulo, Brazil, there has been a constant increase in the incidence of serogroup C meningococcal disease since the late 1980s. To gain an understanding of changes in serogroup C meningococcal disease over three decades in greater São Paulo, Brazil, 1,059 invasive Neisseria meningitidis serogroup C isolates from 1976 and 2005 were analyzed. Three major clone complexes, sequence type (ST)-11, ST-8, and ST-103, were identified by multilocus sequence typing, and the isolates were characterized by serotyping and 16S rRNA typing. During the 30-year period, there were two major antigenic replacements: from 2a:P1.(5,2) to 2b:P1.3 and subsequently to 23:P1.14-6. All strains of clone ST-103 were characterized as serotype 23 and serosubtype P1.14-6. The origin of 23:P1.14-6 ST-103 complex strains is unknown, but efforts are needed to monitor its spread and define its virulence. The antigenic replacements we observed likely represent a mechanism to sustain meningococcal disease in the population as immunity to circulating strains accumulated.

Resposta imune a uma vacina protéica antimeningocócica B: estudo da influência de intervalos de tempo entre as imunizações / The immune response to a protein-based meningococcal B vaccine: study of the effect of intervals between doses on the immune response

Uma vacina constituída de vesículas de membrana externa (VMEs) de meningococo sorogrupo B encontra-se em desenvolvimento no Brasil. Uma das etapas mais importantes nesse processo é avaliar a influência do intervalo de tempo entre doses imunizantes, na resposta imune humoral. Com esse objetivo, foram utilizadas populações de camundongos geneticamente homogêneas e heterogêneas. Os animais receberam, por via intramuscular, duas doses de vacina com intervalos de 30 dias - Grupo I e 90 dias - Grupo II. As cinéticas de respostas primária e secundária foram analisadas nas linhagens isogênicas, BALB/c e A/J, em animais geneticamente selecionados segundo a boa ("High") ou má ("Low") produção de anticorpos e em camundongos "Swiss", geneticamente heterogêneos. Os níveis de anticorpos IgG foram determinados por ELISA e sua atividade funcional pelo ensaio bactericida. A especificidade dos anticorpos contra as diferentes proteínas das VMEs do meningococo foi analisada por "Immunoblot". Houve, na resposta secundária, maior produção de anticorpos no Grupo II do que no Grupo I, para os camundongos "Low" e BALB/c, linhagens que, comparativamente às outras populações homogêneas e heterogênea, expressam níveis inferiores de anticorpos após a imunização primária. Essa diferença foi estatisticamente significante para os camundongos da linhagem BALB/c. Os resultados do "Immunoblot" confirmam, por análise visual, um aumento de resposta de anticorpos nos soros dos BALB/c e "Low" do Grupo II, comparativamente aos do Grupo I. O mesmo padrão de resposta não foi observado nos animais que apresentaram altos títulos de anticorpos já na resposta primária. Para todas as linhagens estudadas, não se observou diferença estatisticamente significativa na ação bactericida dos soros entre animais dos Grupos I e II, embora para as linhagens "Low" e BALB/c, tenha sido observada maior produção de anticorpos bactericidas nos camundongos do Grupo II. Esses resultados sugerem que um intervalo maior entre as imunizações poderia influenciar positivamente a maturação de células B de memória, favorecendo principalmente indivíduos que não produzam níveis elevados de anticorpos, indicando uma possível estratégia para o aumento da eficácia das vacinas

Monoclonal antibody to serotype 17 of Neisseria Meningitidis and-their prevalence in brazilian states

Neisseria meningitidis sao diplococos Gram negativos responsaveis por casos de doencas meningococica em todo o mundo. O potencial epidemico de N. meningitidis sorogrupos B e C e claramente mais uma funcao de seus antigenos de sorotipo que de seu polissacaride capsular. Ate recentemente soros hiperimune foram usados para detectar antigenos de sorotipo em bacterias. O advento de anticorpos monoclonais ofereceu a oportunidade de eliminar muitas das reacoes cruzadas e tem melhorado a acuracidade e reprodutibilidade da sorotipagem de meningococo. Nos produzimos um anticorpo monoclonal contra proteina de membrana externa do sorotipo 17 que ate entao tem sido detectado atraves do uso de soro policlonal. A prevalencia deste epitopo de sorotipo e baixa nas cepas brasileiras. Usando-se este anticorpo monoclonal em cepas brasileiras, nao pudemos diminuir a porcetagem de cepas sorogrupo C nao tipaveis, entretanto, houve uma diminuicao de 13 por cento em cepas sorogrupo B nao tipaveis e 25 por cento em cepas de outros sorogrupos.

Bacterial agents isolated from cerebrospinal fluid of patients with acquired immunodeficiency syndrome (AIDS) and neurological complications

Amostras de liquido cefalorraquidiano (LCR) de 2083 pacientes com Sindrome de Imunodeficiencia Adquirida (SIDA) e complicacoes neurologicas foram examinados durante um periodo de 7 anos (1984-1990). A porcentagem de pacientes que tiveram pelo menos um agente bacteriano cultivado do LCR foi de 6,2 por cento Mycobacterium tuberculosis foi o mais frequentemente isolado (4,3 por cento), seguido do complexo Mycobacterium avium ou MAC (0,7 por cento), de Pseudomas spp (0,5 por cento), Enterobacter spp (0,4 por cento), e Staphilococcus aureus (0,3 por cento). Entre 130 pacientes com cultura positiva, de 89 (68,5 por cento) foi isolado o M. tuberculosis e de 15 (11,6 por cento) MAC. A frequencia de isolamentos bacterianos foram mais frequentemente isolados de pacientes na faixa etaria de 21-30 anos e de mulheres (p<0.050).

Investigaçäo e isolamento de Leishmania: criopreservaçäo de amostras de biópsias de lesöes cutâneas na leishmaniose tegumentar experimental / Investigation and isolation of leishmania: cryopreservation of samples of biopsies from skim lesions in experimental cutaneous leishmaniasi

Foi investigada a viabilidade do isolamento de Leishmania(V.) braziliensis e L.(L.)amazonensis a partir da criopreservaçäo, a -20grausC, -70grausC e -196grausC, de amostras de biópsias de lesöes cutâneas de hamsters(Mesocricetus auratus) experimentalmente infectados. Biópsias de 2mm de diâmetro foram obtidas de lesöes de patas de hamsters. Metade das biópsias foi acondicionada em tubos de poliestireno para congelamento, contendo 1,0ml de soluçäo salina estéril e 0,1ml de glicerol. As amostras restantes foram, individualmente, maceradas em soluçäo salina estéril e acondicionadas em alíquotas de 1,0ml em tubos de poliestireno para congelamento, com 0,1ml de glicerol. Foram constituídos três grupos de tubos, que foram mantidos, inicialmente, por uma noite a 4grausC, sendo transferidos sucessivamente para -20grausC, -70grausC e -196grausC, que foram as temperaturas de manutençäo, respectivamente, para os grupos 1,2 e 3, que assim permaneceram por um período de 60 dias. Após este período as amostras foram descongeladas e examinadas em esfregaços, culturas e inoculaçöes desses materiais. Ambas as espécies de Leishmania sobreviveram na condiçäo de manutençäo estabelecida para o grupo 1, ou seja -20grausC, tanto em biópsia como em homogenizado de macerado de biópsia. L.(L.) amazonensis sobreviveu, também, na condiçäo de manutençäo do grupo 3, a -196grausC