Investigation on the carriage prevalence of Neisseria meningitidis in healthy population in Jiangsu Province in 2019 and 2020 / 中华预防医学杂志

In order to investigate carriage status and serum groups distribution of Neisseria meningitidis(Nm) among healthy population in Jiangsu Province, four counties were selected as monitoring sites by random sampling method for cross-sectional study. Throat swab specimens were collected from four monitoring sites in October to November 2019 and November to December 2020 for bacterial culture and Real-time PCR detection. Chi-square test was used to compare the positive rate of Neisseria meningitidis, and multiple logistic regression model was used to analyze the influencing factors of Neisseria meningitidis carrier rate. The results showed that among 1 512 samples, 57 strains of Nm were isolated, and the carrier rate was 3.77%. Serogroup B was the dominant group (36.84%), followed by un-known serogroups (33.33%), serogroup C was the third (17.54%), serogroup W135 and serogroup A were 7.02% and 5.26%, respectively. The carriage rate (8.60%) of 15-20 years old was significantly higher than others (1.77%-3.74%)(Pearson χ2=18.211, P<0.05). Region, age and immunization history were risk factors for Neisseria meningitidis carrier rate. In summary, the Nm carrier rate of healthy population in Jiangsu Province is relatively low, which indicates that the epidemic cases will continue to be sporadic in the future. However, the prevention and control of meningococcal epidemics on campus should be strengthened, and the monitoring of neisseria meningitidis group B should be maintained as it has become the dominant epidemic strain.

Immunoadsorption therapy for a meningococcemia patient with myocarditis, adrenal hemorrhage, and purpura fulminans: a case report

Abstract Neisseria meningitidis, also known as meningococcus, is a relatively uncommon cause of invasive infection, but when it occurs, it is frequently severe and potentially life-threatening. A ten-year-old female patient developed a purpuric rash with fever. Upon arrival to the pediatric intensive care department, she was unconscious and in a poor general condition. We combined treatment with antibiotics, volume resuscitation, hydrocortisone, and CytoSorb® therapy resulted in a stabilization of hemodynamics, as well as control of hyperinflammation. We observed a significant decrease in vasopressor dosage in this patient.

Aislamiento de Neisseria meningitidis en muestra anorectal en hombre que tiene sexo con hombre con uretritis y sifilis primaria / Isolation of Neisseria meningitidis in anorectal specimen in a men who have sex with men with uretritis and primary syphilis

Resumen Neisseria meningitidis es una bacteria gramnegativa asociada frecuentemente a enfermedades invasoras de elevada mortalidad. Si bien su reservorio natural es la nasofaringe humana, en los últimos años han aumentado los aislamientos de este agente en la mucosa anorectal, principalmente en hombres que tienen sexo con hombres (HSH). Presentamos el caso de un HSH con infección por VIH, que consultó por un cuadro de uretritis y sifilis primaria, en el cual se aisló N. meningitidis en una muestra anorectal. Fue tratado en forma empírica con ceftriaxona y azitromicina, realizándose un cultivo de control post-tratamiento que fue negativo. A pesar del aumento de las infecciones y colonizaciones anogenitales por N. meningitidis, se desconoce su rol como patógeno genital, en la transmisión de otras infecciones y la necesidad de esquemas terapéuticos específicos.

Abstract Neisseria meningitidis is a Gram-negative bacterium frequently associated with invasive diseases with high mortality. Although its natural reservoir is the human nasopharynx, in recent years there have been increasing reports of isolation of this agent in the anorectal mucosa, mainly in men who have sex with men (MSM). We present the case of an HIV-positive MSM who consulted for urethritis and primary syphilis, in which N. meningitidis was isolated in an anorectal specimen. He was treated empirically with ceftriaxone and azithromycin, and a post-treatment control culture was negative. Despite the increase in anogenital infections and colonization by N. meningitidis, its role is unknown as a genital pathogen and in the transmission of other infections and the need for specific therapeutic regimens.

Epidemiological and etiological analysis of two infantile cases of serogroup B epidemic cerebrospinal meningitis epidemics in Shandong Province, 2021 / 中华预防医学杂志

Two cases of epidemic situation of serogroup B meningitis in infants in Shandong Province in 2021 were investigated. Samples of cases and their close contacts were collected for isolation, culture and identification of Neisseria meningitides (Nm). The isolates were subjected to multi-locus sequence typing, outer membrane protein porA and fetA genotyping and drug sensitivity test. Two laboratory-confirmed outbreaks of serogroup B meningitis were reported from Yantai city and Linyi city. The indicated cases were infants aged 5 months and 2 months old respectively. They were not vaccinated with meningitis vaccine. Their epidemiological characteristics and clinical manifestations were similar and the prognosis was good. The same sequence type (ST) of serogroup B Nm strains as the indicated cases was detected in the samples of close family contacts, but without subsequent cases. Among them, Yantai strain was were identified as the type ST-8920, belonging to CC4821 clonal complex, and the genotypes of porA and fetA were p1.21-2, 23 and F3-1. Linyi strain was a new type, belonging to CC4821 clonal complex and the genotypes of porA and fetA were p1.20, 23 and F1-91. The above strains were resistant to penicillin, ciprofloxacin, levofloxacin and Chemitrim, and their sensitivity to cephalosporin decreased. Two cases of infant serogroup B epidemic were relatively rare in China, which were different from the epidemiological and pathogenic characteristics of other Nm serogroups in the past.

Research progress on immunogenicity evaluation of serogroup B meningococcal vaccine / 中华预防医学杂志

Epidemic cerebrospinal meningitis (meningococcal meningitis) is an acute respiratory infectious disease with high mortality and serious sequelae. Meningococcal vaccine is an effective measure to prevent and control meningococcal meningitis. At present, group B meningococcal meningitis has become the main prevalent serum group in the world, including China. Meningococcal ACYW and other vaccines are mainly composed of capsular polysaccharides, while the main component of group B meningococcal vaccine is protein, including outer membrane vesicles (OMV) and recombinant protein vaccine. The methods for evaluating the immunogenicity of group B meningococcal vaccine include hSBA and alternative methods such as meningococcal antigen typing system (MATS), flow cytometric meningococcal antigen surface expression assay (MEASURE), genetic meningococcal antigen typing system (gMATS) and bexsero antigen sequence type (BAST). The evaluation of vaccine immunogenicity is the basis of vaccine development and clinical trial research, However, at present, there is no group B meningococcal vaccine in China. Therefore, in this paper, the research progress of immunogenicity evaluation of group B meningococcal vaccine has been reviewed, in order to provide technical guidance for the research and development of group B meningococcal vaccine, immunogenicity evaluation and clinical trial research in China.

Experimental studies using OMV in a new platform of SARS-CoV-2 vaccines

Although COVID-19 vaccines have recently been approved for emergency use, search for new vaccines are still urgent, since the access of the countries, especially the poorest, to the vaccines, has shown to be slower than the necessary to rapidly control the pandemic. We proposed a novel platform for vaccine using recombinant receptor binding domain (rRBD) from Sars-Cov-2 spike protein and Neisseria meningitidis outer membrane vesicles (OMVs). The antigen preparation produced a humoral and cellular immune response. Taken together our findings suggest a good immunostimulatory patter in response to immunization with rRBD plus N. meningitidis OMV.

Trajectory of serogroups causing Invasive Meningococcal Disease in Santa Catarina state, Brazil (2007-2019)

Abstract The aim of this study was to compare the trajectory of serogroups causing Invasive Meningococcal Disease (IMD) in the Santa Catarina (SC) state with those of whole Brazil. A retrospective analysis of all IMD cases reported from January 2007 to December 2019 was carried out. During the study period, 26,058 IMD cases were registered in Brazil and 644 and in SC state alone. Overall, Brazil showed progressive reduction in cases since 2010, when the meningococcal C conjugate vaccine was introducted on National Immunization Program, while SC showed an increase in total cases since 2013, particularly from serogroups W and C. Serogroups distribution was significantly different between Brazil and SC. The emergence of serogroup W highlights the improved meningococcal surveillance through increased accuracy in identification methods in SC state. This finding is important for discussing recommendations of quadrivalent (ACWY) conjugate vaccines in different geographical areas of Brazil.

Neisseria meningitidis aislada de muestras de hombres que tienen sexo con hombres / Neisseria meningitidis isolated from patients in men who have sex with men

Resumen En los períodos 2000-2004 y 2014-2015 se investigó la presencia de Neisseria meningitidis en 1.143 y 544 hombres que tienen sexo con hombres respectivamente, atendidos en el marco de un programa de enfermedades de transmisión sexual. Se determinó la prevalencia de este agente, su distribución en serogrupos y su sensibilidad a los antimicrobianos. Se obtuvieron hisopados faríngeos, rectales y uretrales, que se sembraron en medio selectivo Thayer Martin modificado. La identificación se realizó mediante pruebas bioquímicas convencionales y por espectrometría de masas (MALDI-TOF). En el segundo período estudiado, sobre 85 aislamientos procedentes de faringes se investigaron los serogrupos B, C, W e Y mediante PCR. Se determinó la CIM de penicilina, ceftriaxona, rifampicina, azitromicina y ciprofloxacina en 66 aislamientos obtenidos en el primer período y en 102 logrados en el segundo. La prevalencia de N. meningitidis fue del 17,8% en el primer período y del 28,1% en el segundo; este microorganismo se aisló más frecuentemente de fauces. Los serogrupos hallados fueron B (31,5%), Y (7,6%) y W (3,3%), con un 9,8% de aislamientos no capsulados; los restantes corresponderían a otros serogrupos. El 34,8% y el 63,7% de los aislados estudiados correspondientes al primer y segundo período, respectivamente, tuvieron sensibilidad intermedia a la penicilina, y un 11,8% de los evaluados en el segundo período fueron resistentes a dicho antibiótico. Todos los aislados estudiados fueron sensibles a ceftriaxona y a ciprofloxacina (excepto 3, con CIM entre 0,25 y 0,5(g/ml), el 3% fueron resistentes a rifampicina y el 2% fueron no sensibles a azitromicina. La portación de N. meningitidis en hombres que tienen sexo con hombres fue elevada y hubo un alto porcentaje de cepas no sensibles a penicilina. El serogrupo B fue prevalente.

Abstract During the periods 2000-2004 and 2014-2015, Neisseria meningitidis was investigated in men who have sex with men, 1143 and 544 respectively, who consulted in the sexually-transmitted disease program. Prevalence, serogroup distribution and susceptibility to antibiotics were determined. Pharyngeal, rectal and urethral swabs were cultivated on selective Thayer-Martin modified medium. The identification was performed by biochemical tests and mass spectrometry by MALDI-TOF. Serogroups B, C, W and Y were investigated by PCR in 85 isolates recovered from the pharynx belonging to the second period. MICs of penicillin, ceftriaxone, rifampicin, azithromycin and ciprofloxacin were determined for 66 and 102 isolates from periods 1 and 2 respectively, according to CLSI. The prevalence of N. meningitidis was 17.8% and 28.1%, in periods 1 and 2 respectively; the isolates were mainly recovered from the pharynx. The distribution of serogroups was B 31.5%; Y 7.6%; W 3.3% and 9.8% non-capsulated and the rest would belong to other serogroups. Isolates classified as intermediate to penicillin were 34.8% and 63.7% (first and second periods, respectively); moreover, 11.8% of the isolates from the second period were resistant. All isolates were susceptible to ceftriaxone, to ciprofloxacin (except 3 isolates with MIC values between 0.25 and 0.5(g/ml), 3% were resistant to rifampicin and 2% were not susceptible to azithromicin. The prevalence of N. meningitidis carriage in men who have sex with men was high with a high rate of penicillin non-susceptible isolates. B was the prevalent serogroup.

Impacto do uso da reação em cadeia da polimerase para o diagnóstico de meningite bacteriana em substituição a contraimunoeletroforese / Impact of using polymerase chain reaction for the diagnosis of bacterial meningitis in substitution for counterimmunoelectrophoresis

Introdução: a meningite bacteriana é um grave problema de Saúde Pública mundial, tendo como principais agentes: Neisseria meningitidis, Streptococcus pneumoniae e Haemophilus influenzae. A metodologia de diagnóstico empregada no Instituto Adolfo Lutz ­ Centro de Laboratório Regional Santo André até o ano de 2011 era a contraimunoeletroforese (CIE), depois foi substituída pela reação em cadeia da polimerase em tempo real (qPCR), que apresenta maior sensibilidade. Objetivo: este trabalho objetivou comparar ambas as metodologias no período de 2009 a 2018, para avaliação do impacto da introdução da qPCR no diagnóstico das meningites bacterianas nos 7 municípios da região do ABC do Estado de São Paulo. Metodologia: foram avaliadas a quantidade total de exames realizados, a média mensal, a positividade no período, os municípios requisitantes e a prevalência das bactérias causadoras de meningite, no período de abril/2009 até dezembro/2018. Resultados: Foram 377 exames de CIE e 1305 de qPCR, com média anual de 230 exames em 2010-2013 e 130 exames em 2014-2018. Observou-se aumento da positividade entre as técnicas, 17,8% para CIE e 33,8% para qPCR. N. meningitidis foi responsável pela maioria dos casos entre 2011 e 2013, cerca de 61% dos casos positivos, enquanto que entre 2014 e 2018 foi S. pneumoniae, cerca de 53%. Conclusão: os resultados indicaram que a qPCR foi mais eficiente em detectar os agentes causadores de meningite bacteriana na região do que a técnica de CIE. Por fim, este trabalho suporta a implantação da metodologia de qPCR para diagnóstico de meningite em substituição de técnicas menos sensíveis.

Introduction: bacterial meningitis is still a serious worldwide public health problem, and the main etiological agents are: Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae. The diagnostic methodology employed at the Adolfo Lutz Institute ­ Santo André Regional Laboratory Center until 2011 was the ounterimmunoelectrophoresis (CIE), then it was replaced by the real-time polymerase chain reaction (qPCR), which is more sensitivity. Objective: this study aimed to compare both methodologies from 2009 to 2018 to evaluate the impact of the introduction of qPCR in the diagnosis of bacterial meningitis in the 7 cities of the ABC region of São Paulo State. Methodology: the total number of tests performed, the month average, the positivity in the period, the requesting cities and the prevalence of bacteria causing meningitis were evaluated from April/2009 to December/2018. Results: there were 377 CIE exams and 1305 qPCR exams, with an annual average of 230 exams in 2010-2013 and 130 exams in 2014-2018. There was an increase in positivity between the performed techniques, 17.8% for CIE and 33.8% for qPCR. N. meningitidis accounted for most cases of bacterial meningitis between 2011 and 2013, about 61% of positive cases, whereas between 2014 and 2018 it was S. pneumoniae, with about 53%. Conclusion: the results indicated that qPCR was more efficient in detecting the agents that cause bacterial meningitis in the region than the CIE technique. Finally, this work supports the implementation of qPCR methodology for diagnosis of meningitis in replacement of less sensitive techniques.

The importance of the postmortem interval for the diagnosis of Waterhouse­Friderichsen syndrome by Neisseria meningitidis in a series of forensic cases

The effective value of microbiological post-mortem examinations stands as fundamental in forensic cases involving microbiology. We ran these analyses on five victims, who suddenly died after showing persistent fever. The examinations were conducted between 48 hours and 10 days after death, and adrenal gland apoplexy was detected in all the cases. Microbiological examinations identified Neisseria meningitidis, which was accountable for Waterhouse­Friderichsen syndrome. Diplococci were isolated from three cadavers that underwent forensic dissection between 2 and 3 days after death. The remaining two cadavers showed polymicrobial contamination, and a polymerase chain reaction technique was necessary to identify the pathogen. We assumed that the microbial overlap could lead to diagnostic mistakes and conceal the identification of the lethal pathogen. Therefore, we suggest using molecular techniques for a postmortem interval (PMI) longer than 72 hours. Classical microbiological examination should be performed for PMI within 72 hours.

Carriage prevalence of Neisseria meningitidis in the Americas in the 21st century: a systematic review

Abstract Neisseria meningitidis is a bacterium that colonizes the human nasopharynx and is transmitted by respiratory droplets from asymptomatic or symptomatic carriers. Occasionally, the pathogen invades the mucosa and enters the bloodstream, causing invasive meningococcal disease, a life-threatening infection. While meningococcal colonization is the first step in the development of invasive disease, the risk factors that predict progression from asymptomatic to symptomatic status are not well-known. The present report aimed to describe the prevalence of N. meningitidis carriers throughout the Americas, emphasizing the risk factors associated with carrier status, as well as the most prevalent serogroups in each studied population. We conducted a systematic review by searching for original studies in the MEDLINE/PubMed, Embase, LILACS and SciELO databases, published between 2001 and 2018. Exclusion criteria were articles published in a review format, case studies, case control studies, investigations involving animal models, and techniques or publications that did not address the prevalence of asymptomatic carriers in an American country. A total of 784 articles were identified, of which 23 were selected. The results indicate that the highest prevalence rates are concentrated in Cuba (31.9%), the United States (24%), and Brazil (21.5%), with increased prevalence found among adolescents and young adults, specifically university students and males. The present systematic review was designed to support epidemiological surveillance and prevention measures to aid in the formulation of strategies designed to control the transmission of meningococci in a variety of populations and countries throughout the Americas.

A meningococcal B vaccine induces cross-protection against gonorrhea

PURPOSE: Neisseria meningitidis and Neisseria gonorrhoeae share between 80% and 90% of their genetic sequence. Meningococcal serogroup B vaccines based on outer membrane vesicles—such as VA-MENGOC-BC—could cross-protect against gonorrhea. The aim of this study was to analyze the incidence rates of gonorrhea and other sexually transmitted diseases with respect to the use of the VA-MENGOC-BC vaccine. MATERIALS AND METHODS: Health statistics between 1970 and 2017 were reviewed and the incidence of meningococcal disease and sexually transmitted diseases (gonorrhea, syphilis, condyloma acuminatum, hepatitis B and human immunodeficiency virus infection) were analyzed during the pre- and post-vaccination periods. Gonorrhea incidence was also analyzed by age groups. RESULTS: VA-MENGOC-BC was successfully used to control a meningococcal epidemic in Cuba. The strategy to combat the epidemic was carried out in two stages. The first one was a nationwide mass-vaccination campaign from 1989 to 1990, targeting the population at highest-risk aged 3 months to 24 years. During the second stage, begun in 1991, it was included in the Expanded Immunization Program. Gonorrhea incidence increased from 1970 to 1989. However, after the VA-MENGOC-BC massive vaccination campaign a sharp decrease of gonorrhea incidence was observed. It lasted between 1989 and 1993. A second incidence peak was detected in 1995, but it dropped again. Data clearly show a decline in the incidence of gonorrhea following massive vaccination, in contrast with other sexually transmitted diseases. Incidence rates in unvaccinated age groups also decreased, probably due to herd immunity. CONCLUSION: There is evidence that VA-MENGOC-BC could induce a moderate protection against gonorrhea.

Prevalência e fatores associados ao estado de portador de Neisseria spp. em núcleos familiares: estudo de base populacional / Prevalence and factors associated with Neisseria spp. carrier state in family households population-based study

Introdução - O estado de portador assintomático ocorre quando o hospedeiro alberga o agente etiológico sem apresentar doença. Os fatores associados ao estado de portador de Neisseria não patogênica (NNP) e Neisseria meningitidis (Nm) diferem entre si, no entanto, as características epidemiológicas de ambas ainda são pouco exploradas. Objetivos - Estimar a prevalência, analisar possíveis diferenças em distintos estratos sociais, identificar o genótipo das cepas isoladas, assim como, investigar fatores associados ao estado de portador de Nm e de NNP em núcleos familiares residentes em Cuiabá-MT. Método - Estudo transversal de base populacional, desenvolvido de 07/2016 a 07/2017, incluindo todos os moradores de uma amostra probabilística estratificada composta de 243 núcleos familiares (domicílios) de área urbana, em bairros de alta e baixa renda do município de Cuiabá. Foram incluídos os domicílios com ao menos uma criança de 12 e 60 meses de idade. Todos os residentes nos domicílios selecionados foram submetidos a coleta de swab de orofaringe para o isolamento de Neisseria spp. Para a comparação de proporções utilizou-se o teste do qui-quadrado. Foram estimadas as razões de prevalências (RP) com seus respectivos intervalos de confiança 95% (IC95%) e para a investigação de fatores associados ao estado de portador de Nm e de NNP foram utilizados modelos de regressão de Poisson. O ajuste das variáveis no modelo final foi avaliado pelo teste de Hosmer e Lemeshow. Resultados: Foram estudados 1.050 indivíduos residentes em 233 núcleos familiares. A prevalência de portadores de Neisseria spp. foi de 10,6% (111/1.050), a de Nm de 2,4% (25/1.050) e de NNP de 8,2% (86/1.050). Dentre 111 portadores, 62 (56,0%) foram por N. lactamica, 25 (22,0%) por Nm, 21 (19,0%) por N. subflava., duas (2,0%) por N. mucosa e uma (1,0%) por N. polysaccharea. Das Nm, 76% (19/25) eram não grupáveis, 16% (4/25) eram do sorogrupo B, 4% (1/25) do sorogrupo C e 4% (1/25) do sorogrupo W. A prevalência de Nm em bairros de baixa renda foi de 2,8% (23/816) e nos de alta renda de 0,8% (2/234) (p=0,058), com uma razão de prevalência (RP) de 3,3 (IC95%:0,8-13,9). A prevalência de NNP em bairros de baixa renda foi de 8,2% (67/816) e em bairros de alta renda de 8,1% (19/234), com uma RP de 1,0 (IC95%:0,6-1,6). Permaneceram independentemente associados ao estado de portador de Nm após ajuste para conviver com tabagista no domicílio e por número de pessoas por dormitório: i) residir em bairro de baixa renda (RPajustada=2,6); ii) faixa etária de 5 a 14 anos (RPajustada=2,7); iii) faixa etária de 15 a 29 anos (RPajustada=2,4) e faixa etária de 30 e anos e mais (RPajustada=1,4). Após o ajuste para a infecção respiratória nos últimos cinco dias, apresentar asma, três ou mais pessoas por dormitório e sexo masculino, mostraram-se independentemente associados ao estado de portador de NNP: i) pertencer a faixa etária de cinco a 14 anos de idade (RPajustada=2,8) e de menores de cinco anos de idade (RPajustada=7,2); ii) residir em casa precária/quitinete (RPajustada=2,1). Conclusões - O contexto social influencia o estado de portador de Nm e NNP. As vacinas conjugadas meningocócicas podem prevenir doenças direta e indiretamente e tais resultados podem subsidiar a elaboração de estratégias de intervenção, especialmente para a identificação de grupos alvo de programas de vacinação

Introduction - The asymptomatic carrier state occurs when the host harbors the etiologic agent without presenting disease. The associated factors with the carrier state of non-pathogenic Neisseria (NNP) and Neisseria meningitidis (Nm) differ among them, however, the epidemiological characteristics of both are still poorly explored. Objectives - To estimate the prevalence, to analyze possible differences in different social strata, to identify the genotype of the isolated strains, as well as to investigate associated factors with the Nm and NNP carrier state in family\'s households living in Cuiabá-MT. Methods - A cross-sectional study was conducted in 07/2016 a 07/2017, in the city of Cuiabá, including all residents of a stratified probabilistic sample which was composed by 243 urban households (families nucleus) with high and low income neighborhoods of the city of Cuiabá. Households with at least one child between 12 and 60 months age were included. All residents in the selected households were submitted to oropharynx swab collection for the isolation of Neisseria spp. To compare proportions the chi-square test was used. For the estimates of prevalence ratios (PR) and the respective 95% confidence intervals (95% CIs), for the analysis of the associated factors with Nm and NNP carrier state Poisson regression models were used. The adjustment of the variables in the final model was evaluated by the Hosmer e Lemeshow test. Results - A total of 1,050 individuals residing in 233 families nucleus were studied. The prevalence of Neisseria spp. was of 10.6% (111/1,050), Nm of 2.4% (25/1,050) and NNP of 8.2% (86/1,050). Among 111 carriers, 62 (56.0%) were by N. lactamica, 25 (22.0%) by Nm, 21 (19.0%) by N. subflava, two (2.0%) by N. mucosa and one (1.0%) by N. polysaccharea. Of the Nm, 76% (19/25) were non-grouping, 16% (4/25) were serogroup B, 4% (1/25) serogroup C and 4% (1/25) serogroup W. Prevalence of Nm in low-income neighborhoods was 2.8% (23/816) and high-income (0.8%) (2/234) (p=0.058), with a prevalence ratio of 3.3 (95% CI:0.8-13.9). The prevalence of NNP in low-income neighborhoods was 8.2% (67/816) and in high-income neighborhoods of 8.1% (19/234), with a PR of 1.0 (95% CI:0,6-1,6). They remained independently associated with Nm state after adjusting to live with a smoker at home and by number of people per dormitory: i) living in a low-income neighborhood (PRadjusted=2.6); ii) age group of 5 to 14 years (PRadjusted=2.7); iii) age range of 15 to 29 years (PRadjusted=2.4) and age group of 30 years and over (PRadjusted=1.4). After adjusting for respiratory infection in the last five days, presenting asthma, three or more people per dormitory and male sex, were independently associated with NNP status: i) belonging to the age group of five to 14 years of age (PRadjusted=2.8) and of children under five years of age (RPadjusted=7.2); ii) residing in a precarious home/kitchenette (PRadjusted= 2.1). Conclusions - The social context influences the carrier state of Nm and NNP. Meningococcal conjugate vaccines can prevent diseases directly and indirectly and such results may support the development of intervention strategies, especially for the identification of target groups of vaccination programs