Meningococcal disease and carriage in the Philippines: A review of recent data

@#This article reviews recent data on meningococcal disease and carriage in the Philippines. It aims to provide information on the epidemiology of meningococcal disease, its carriage, data on prevention, and the impact of vaccination on disease and carriage. The World Health Organization considers the Philippines as having low endemicity for meningococcal disease. However, current data underestimates the true burden in the country due to many factors. In recent years, data from the Philippines show a high case-fatality rate since only the septicemic form is being reported. Studies on asymptomatic meningococcal carriage rates are sparse, with one study by Gonzales, et al. investigating the prevalence of meningococcal nasopharyngeal carriage in Filipinos aged 5-24 years old living in an urban setting. The study showed that the overall prevalence of carriage was 3.7% and was highest (9%) among the 10-14 age group. Serogroup B was the most common isolate. Effective meningococcal vaccines are available. Although not included in the National Immunization Program, medical societies recommend giving vaccines to individuals at high risk of infection. Data on local epidemiology accounting for the disease and asymptomatic carriage are important to strengthen future programs on immunization and prevention of meningococcal disease.

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.

Maternal vaccination: A narrative review

Background: Vaccinations in general are considered to be one of the greatest achievements in medicine, saving millions of lives globally. Aim: This narrative review highlights issues related to vaccination in pregnancy and provides information on those vaccines registered for use in pregnancy. Method: Published articles on vaccinations in pregnancy are included in this review. The search engines used included PubMed, Medline, Google Scholar, and ScienceDirect. Results: Vaccinations during pregnancy are more likely to be administered in high income countries (HICs) compared to low-income countries (LICs) due to easier access to healthcare services and better communicable disease awareness. Maternal and perinatal morbidity and mortality rates associated with infectious diseases are higher in LICs with access to maternal care services, infrastructure and hospital equipment lacking in these settings. Conclusion: Suitable vaccinations are recommended for use in pregnancy to prevent harm to women, their foetuses and newborns from some communicable diseases, and they have resulted in declines in maternal and infant morbidity and mortality. Furthermore, this review has shown that vaccination during pregnancy is not only safe for both the woman and her foetus but also effective. Therefore, health professionals and national governments should strongly consider approved vaccinations prior to or during pregnancy.

Association between circulating exhausted CD4+ T cells with poor meningococcal C conjugate vaccine antibody response in HIV-infected children and adolescents

OBJECTIVES: To investigate the expression levels of surface markers of activation (CD38 and HLA-DR), inhibition (PD-1, TIGIT and CD57) and co-stimulation (CD28 and CD127) on CD4+ T cells of children/adolescents with vertical HIV infection (HI patients) and HIV-uninfected (HU) controls vaccinated with the meningococcal C conjugate vaccine (MCC). METHODS: HI patients (n=12), aged 8-17 years, were immunized with two MCC injections, while HU controls (n=9), aged 5.3-10.7 years, received a single MCC dose (as per national recommendation at the time of this study, a single MCC vaccine dose should be given for healthy children and youth aged 1-18 years). The HI patients were categorized according to the combined antiretroviral therapy (cART) treatment. Blood samples were obtained before vaccination, after priming, and after the administration of a booster dose of vaccine to determine the serum bactericidal antibody (SBA) titers and the expression levels of surface markers on CD4+ T cells by flow cytometry. The levels of serum cytokines, IL-4 and CXCL-13 were also measured using Luminex kits. RESULTS: The co-expression of the TIGIT-HLA-DR-CD38 molecules increased in the CD4+ T cells of HI patients/no-cART who also showed a lower frequency of CD127+CD28+ CD4+ T cells than HI patients/cART and HU group subjects. There were significant negative correlations between the frequency of exhausted CD4+ T cells and the SBA response. IL-4 levels were higher in HI patients/cART and positively correlated with SBA titers but negatively associated with the expression of exhaustion markers. Moreover, the CXCL-13 levels were positively correlated with the exhausted CD4+ T cells. CONCLUSION: The results of our study suggest that the co-expression of exhaustion markers and/or loss of co-stimulatory molecules influence the SBA response in HI patients.

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.

Limitaciones del ensayo bactericida en suero para la evaluación de vacunas contra meningococo B / Limitations of the serum bactericidal assay for the evaluation of meningococcal B vaccines

Las vacunas antimeningocócicas contra los serogrupos A, C, Y, W135, X se basan en sus polisacáridos capsulares, estructura que les confiere resistencia a los mecanismos de defensa del hospedero mediados por el sistema del complemento.1 El polisacárido capsular de Neisseria meningitidis serogrupo B no ha podido ser empleado por su pobre inmunogenicidad, debido a su semejanza con el ácido siálico expresado en las moléculas de adhesión de las células neuronales. Por ello se han evaluado otros inmunógenos. Entre estos se destacan las vacunas basadas en vesículas de membrana externa (VME).2,3 El ensayo bactericida en suero (EBS) es la regla de oro para evaluar la inmunogenicidad de vacunas antimeningocócicas. Se ha considerado como correlato de protección aquellos valores superiores o iguales a 1:8 para vacunas de polisacáridos, en especial cuando se usa complemento humano. Para vacunas contra meningococo B títulos de al menos 1:4.3,4 Sin embargo, el EBS subestima el grado de protección contra meningococo B.2,3 Hay que tener en cuenta que este ensayo fue diseñado para evaluar la lisis celular mediada por la activación de la vía clásica del complemento; útil en contextos de estructuras con epitopos repetitivos y espacialmente asequibles, lo que si bien es evidente en cápsulas de polisacáridos, no lo es para VME. Considero que esta extrapolación no es adecuada. Por otra parte, otros mecanismos de protección...(AU)

Vacuna cubana antimeningocócica VA-MENGOC-BC®: Treinta años de uso y potencialidades vigentes / Cuban Meningococcal Vaccine VA-MENGOC-BC®: 30 Years of Use and Future Potential

La enfermedad meningocócica provoca cada año más de 500.000 casos y 85.000 muertes en el mundo y un 20 por ciento de los sobrevivientes sufre secuelas. En Cuba, en 1980, la incidencia llegó a 14,4 por 100.000 habitantes para todas las edades y fue declarada como el principal problema de salud del país. En niños menores de 1 año se reportaron más de 120 casos por 100.000 habitantes en algunas provincias. En 1989, investigadores en La Habana, Cuba desarrollaron una vacuna contra meningococo B y C; VA-MENGOC-BC®, la primera en el mundo eficaz contra el meningococo del serogrupo B. Su eficacia de 83 por ciento se demostró en un estudio de campo prospectivo a doble ciegas, aleatorizado, contra placebo. En su producción se empleó por primera vez la tecnología vesicular o proteoliposómica. Esta vacuna se usó en una campaña de vacunación masiva y posteriormente fue incluida en el Programa Ampliado de Inmunización en Cuba y tuvo un impacto acumulado sobre la incidencia de la enfermedad meningocócica del serogrupo B superior a 95 por ciento (93 por ciento-98 por ciento). La vacunación masiva y sistemática cambió el espectro de cepas del meningococo en los portadores asintomáticos sanos y la circulación de cepas en las poblaciones hacia fenotipos no virulentos. La enfermedad dejó de ser un problema de salud en el país. VA-MENGOC-BC® es la vacuna contra la enfermedad meningocócica del serogrupo B que se aplicó en el mayor número de susceptibles en el mundo. En América Latina se administraron más de 60 millones de dosis. En varios países donde se ha usado VA-MENGOC-BC®, circulan cepas diferentes a la vacunal y contra todas ellas se demostró un elevado porcentaje de efectividad (55%-98 por ciento en menores de 4 años y 73 por ciento-100 por ciento en mayores de 4 años). VA-MENGOC-BC® y su tecnología proteoliposómica han tenido impacto y mantienen su potencialidad, no solo en la enfermedad meningocócica, sino en el desarrollo de otras vacunas y adyuvantes(AU)

Every year, meningococcal infection by Neisseria meningitidis causes over 500,000 cases and 85,000 deaths in the world, with 20 percent of survivors suffering sequelae. In Cuba its incidence in 1980 reached 5.9 cases per 100,000 population; about 80 percent of cases were serogroup B, prompting health authorities to declare meningococcal disease the country's main public health problem. Several provinces reported over 120 cases per 100,000 children aged <1 year, overwhelmingly serogroup B. At that time, no vaccines existed with proven efficacy against N. meningitidis serogroup B, nor was there a vaccine candidate that could be successful in the short term. By 1989, researchers in Havana had developed a Cuban meningococcal B and C vaccine, VA-MENGOC-BC®, the world's first against serogroup B meningococcal disease. Its efficacy of 83 percent was demonstrated in a prospective, randomized, double-blind, placebo-controlled field study. Vaccine production used vesicle or proteoliposome technology for the first time. The same year, the World Intellectual Property Organization awarded its gold medal to the main authors of the VA-MENGOC-BC® patent. The vaccine was used in a mass vaccination campaign and later included in Cuba's National Immunization Program, with a cumulative impact on incidence of serogroup B meningococcal disease greater than 95 percent (93 percent-98 percent). Mass, systematic vaccination shifted the spectrum of meningococcal strains in healthy asymptomatic carriers and strains circulating among population groups toward nonvirulent phenotypes. The disease ceased to be a public health problem in the country. VA-MENGOC-BC® is the most widely applied vaccine against serogroup B meningococcal disease in the world. Over 60 million doses have been administered in Latin America. In several countries where it has been applied, in which strains other than the vaccine-targeted strains circulate, VA-MENGOC-BC® has demonstrated effectiveness against all (55 percent-98 percent in children aged ≥4 years and 73 percent-100 percent in children aged >4 years). The vaccine and its proteoliposome technology have had an impact and continue to have potential, not only for meningococcal disease, but also for development of other vaccines and adjuvants(AU)

A phase Ⅲ clinical trial study on the safety and immunogenicity of ACYW135 group meningococcal conjugate vaccine inoculated in 3 month old infants / 中华预防医学杂志

The aim of this study was to evaluate the safety and immunogenicity of the first domestic ACYW135 meningococcal conjugate vaccine and a control vaccine named AC group meningococcal conjugate vaccine for 3 months (90-119 days) infants. From February 2017 to June 2018, a randomized, blinded, and similar vaccine-controlled clinical trial design was adopted at the Henan Vaccine Clinical Research Base. The subjects were 3 months old healthy infants, a total of 720, based on a 1∶1 ratio. The random allocation table for entry was randomly assigned to the experimental group and the control group. According to the 3, 4, and 5 month-old vaccination procedures, the subjects were vaccinated with test vaccine (ACYW135 group meningococcal conjugate vaccine) and control vaccine (group A group C meningococcal polysaccharide conjugate vaccine), of which 720 were given the first dose, 696 were given the second dose (test group: 346; control group: 350), and 692 were given the third dose (test group: 344; Control group: 348). The overall adverse reaction rate of the test vaccine was 21.90% (230 cases), which was lower than the 32.04% (339 cases) of the control vaccine (0.05). Group Y and W135 was 88.17% (298 cases), 99.41% (336 cases), respectively. The GMT results showed that the test vaccine group A was 56.24, the control vaccine was 57.43 (>0.05); the group C test vaccine (43.53) was higher than the control group (27.28) (<0.001). The group Y and W135 are 89.22 and 140.66, respectively. Among them, the proportion of the group C GMT antibody ≥ 1∶128 for test vaccine (31.07%, 105 cases) was higher than the control vaccine (16.22%, 55 cases) (<0.001). ACYW135 group meningococcal conjugate vaccine has more safety and immunogenicity after application to 3 month old infants.

Estudio de tolerancia local de la vacuna antimeningocóccica VA-MENGOC-BC® en ratas Sprague Dawley. Evaluación a los 24 y 36 meses en estante / Local tolerance study of the VA-MENGOC-BC® antimeningococcal vaccine in Sprague Dawley rats. Evaluation at 24 and 36 months of shelf

La meningitis meningocóccica continua siendo un problema de salud en diferentes países y para la prevención de esta enfermedad se han obtenido diferentes vacunas. La vacuna VA-MENGOC-BC® ha constituido ser eficaz y segura en la prevención de la meningitis meningocóccica contra los serogrupos B y C. Esta ha demostrado buena estabilidad en el tiempo sin cambiar su calidad como producto; fue conservada a estante durante 24 y 36 meses a temperaturas de 4 a 8 °C. Se evaluó su posible potencial toxicológico a través de un estudio de tolerancia local en ratas Sprague Dawley para extender su vida útil. Los animales inmunizados se observaron diariamente para evaluar síntomas locales y sistémicos de toxicidad. Se realizaron evaluaciones del peso corporal, consumo de agua y alimento, termometría, musculometría e irritabilidad dérmica por el método de Draize. Se realizaron estudios anatomopatológicos periódicos para observar posibles efectos adversos. No se observaron síntomas de toxicidad ni muertes. No se encontraron diferencias entre los grupos experimentales en cuanto al peso corporal, el consumo de agua y de alimentos, no se evidenció fiebre, ni irritabilidad local. Anatomopatológicamente a nivel del punto de inoculación se observaron procesos granulomatosos de tipo macrofágicos característicos en las vacunas que contienen hidróxido de aluminio. Estos resultados permitieron concluir que la vacuna VA-MENGOC-BC® que permaneció en estante durante 24 y 36 meses no evidenció efectos adversos locales, ni sistémicos en las ratas(AU)

Meningococcal meningitis continues to be a health problem in different countries and different vaccines have been obtained for the prevention of this disease. VA-MENGOC-BC® vaccine has been effective and safe in the prevention of meningococcal meningitis against serogroups B and C. This has shown good stability over time without changing its quality as a product; it was stored on a shelf for 24 and 36 months at temperatures of 4 to 8 °C. Their possible toxicological potential was evaluated through a local tolerance study in Sprague Dawley rats. Immunized animals were observed daily to evaluate local and systemic toxicity symptoms. Body weight, water and feed intake, thermometry, musculometry were performed and dermal irritability by the Draize method. Anatomopathological studies to observe possible adverse effects were made. No symptoms of toxicity or deaths were observed. No differences were found between the experimental groups in terms of body weight, water and food consumption, no fever or local irritability was evident. Anatomopathologically no lesions of diagnostic value were observed, at the site of inoculation, granulomatous processes of macrophagic type characteristic in vaccines containing aluminum hydroxide were observed. These results allowed us to conclude that the VA-MENGOC-BC® vaccine that remained on the shelf for 24 and 36 months did not show any local or systemic effects in rats(AU)

Comparison of Immune Responses to Two Quadrivalent Meningococcal Conjugate Vaccines (CRM197 and Diphtheria Toxoid) in Healthy Adults

BACKGROUND: After the introduction of the meningococcal ACWY-CRM197 conjugate vaccine (MenACWY-CRM) in 2012 and the meningococcal ACWY-diphtheria toxoid conjugate vaccine (MenACWY-DT) in 2014, immunization was recommended for certain high-risk groups including new military recruits in Korea. However, comparative immunogenicity studies for these vaccines have not been performed in Korea. Here, we compared the immunogenicity of these two vaccines in healthy adults. METHODS: A total of 64 adults, 20–49 years of age, were randomly divided into two groups (1:1) to receive either of the two vaccines. The sera were obtained before and 1 month after vaccination and tested for serogroup-specific serum bactericidal activity using baby rabbit complement. RESULTS: There were no significant differences post-vaccination in the geometric mean indices and the seropositive rate to all serogroups between the vaccines. The proportion of seropositive subjects after vaccination ranged from 88% to 100%. CONCLUSION: Both meningococcal conjugate vaccines showed good immunogenicity in healthy Korean adults without statistically significant differences. Further investigations for serotype distribution of circulating meningococci and the immune interference between other diphtheria toxin-containing vaccines concomitantly used for military recruits are needed to optimize immunization policies. TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0002460

Experts' consensus on immunization with meningococcal vaccines in China / 中华预防医学杂志

Meningococcal vaccines in the Chinese market include meningococcal polysaccharide vaccine, meningococcal polysaccharide conjugate vaccine, and a combined vaccine. Meningococcal conjugate vaccines immunization schedules vary by vaccine manufacturer, and often cause confusion in immunization practices. Based on the epidemiological characteristics of meningococcal disease, serogroup distribution of Neisseria meningitidis, and research progress on the immunogenicity and safety of meningococcal vaccines, we developed an experts' consensus on immunization with meningococcal vaccines to provide guidance for immunization providers and for centers for disease control and prevention staff.

Efficacy, safety, and cost-effectiveness of meningococcal vaccines / 中华预防医学杂志

Meningococcal meningitis is an acute, severe respiratory infectious disease caused by Neisseria meningitidis. Immunization with meningococcal vaccine is the most effective measure to control and prevent transmission of meningococcal meningitis. Meningococcal vaccines in the Chinese market include meningococcal polysaccharide vaccine, meningococcal polysaccharide conjugate vaccine, and a combined vaccine containing meningococcal polysaccharide conjugate vaccine. This article reviews research progress on the efficacy, safety, and cost-effectiveness of meningococcal vaccines, particularly in the Chinese market, to support appropriate use of the various meningococcal vaccines for preventing meningococcal meningitis.

Scaling-up fermentation of Escherichia coli for production of recombinant P64k protein from Neisseria meningitidis

Background: P64k is a Neisseria meningitidis high molecular weight protein present in meningococcal vaccine preparations. The lpdA gene, which encodes for this protein, was cloned in Escherichia coli and the P64k recombinant protein was expressed in E. coli K12 GC366 cells under the control of a tryptophan promoter. P64k was expressed as an intracellular soluble protein about 28% of the total cellular protein. Several scale-up criteria of fermentation processes were studied to obtain the recombinant P64k protein at the pilot production scale. Results: The best operational conditions at a larger scale production of P64k recombinant protein were studied and compared using the four following criteria: Constant Reynold's number (Re constant), Constant impeller tip speed (n di constant), Constant power consumption per unit liquid volume (P/V constant) and Constant volumetric oxygen transfer coefficients (KLa/k constant). The highest production of the recombinant protein was achieved based on the constant KLa/k scale-up fermentation criterion, calculating the aeration rate (Q) and the impeller agitation speed (n) by iterative process, keeping constant the KLa/k value from bench scale. The P64k protein total production at the 50 l culture scale was 546 mg l -1 in comparison with the 284 mg l -1 obtained at 1.5 l bench scale. Conclusions: The methodology described herein, for the KLa/k scale-up fermentation criterion, allowed us to obtain the P64k protein at 50 l scale. A fermentation process for the production of P64k protein from N. meningitidis was established, a protein to be used in future vaccine formulations in humans.

Doença meningocócica invasiva nas capitais da Região Sul do Brasil: características e tendências / Invasive meningococcal disease in the capitals of the Southern Region of Brazil characteristics and trends

Objetivos: Analisar a tendência, descrever mudanças no comportamento da doença meningocócica invasiva (DMI) e estimar o impacto da vacina conjugada do meningococo C (VCMC) nas capitais da região Sul do Brasil, no período de 1991 a 2015, assim como, investigar as características sociodemográficas, econômicas e de intervenções tecnológicas associadas aos casos pertencentes a cluster da doença no município de Curitiba (PR), no período de 2001 a 2014. Métodos: As áreas de estudo englobaram as capitais da Região Sul do Brasil: Curitiba (PR), Florianópolis (SC) e Porto Alegre (RS), a população de estudo abrangeu os casos de DMI notificados entre 1991 a 2015 à vigilância da doença e residentes nessas capitais. A definição de caso adotada foi a padronizada pelo Ministério da Saúde. As fontes de dados foram: vigilância da DMI, o Instituto Adolfo Lutz, o Instituto Brasileiro de Geografia e Estatística e o Instituto de Pesquisa e Planejamento Urbano de Curitiba. A tendência da incidência e mortalidade da DMI foi determinada pelo modelo de regressão polinomial. A intensidade e a direção da relação linear entre a taxa de incidência e os indicadores socioeconômicos, de saúde e sorogrupo foram analisadas pelo coeficiente de correlação de Pearson. O impacto da VCMC foi estimado pela Fração Prevenida na População, comparando as taxas de incidência de 2012 e 2015 com as de 2009. Investigou-se os potenciais fatores associados a casos pertencentes a cluster no período de 2001 a 2014 por meio das estimativas de odds ratio não ajustada e ajustadas pela regressão logística múltipla não condicional, com os respectivos intervalos de confiança de 95%. Resultados: No período de estudo, a DMI apresentou três comportamentos distintos nas capitais da região sul: i) epidêmico na década de 1990, ii) declínio das taxas na década de 2000, antes da introdução da VCMC na rotina de imunização e, iii) estacionário com taxas baixas entre 2011 e 2015, sob a influência da VCMC. Observamos nesses períodos a influência de fatores biológicos, socioeconômicos e de saúde na incidência dessas capitais. No estudo mais detalhado em Curitiba, apresentou-se associado aos casos pertencentes a cluster, ajustados no tempo e pela idade, residir em bairros de baixa renda (OR: 2,3, IC95%:1,1-4,5). O sorogrupo predominante foi o B com 65,4%, seguida pelo C com 24,5% e 8,3% pelo W. Possivelmente, em virtude da baixa incidência do sorogrupo C, não se verificou a redução na incidência total da DMI, nestas capitais. Entretanto, no período posterior a VCMC, os casos pelo sorogrupo C foram raros ou zerados na faixa etária destinada a vacinação em Curitiba e Florianópolis. Em Porto Alegre foram registrados casos pelo sorogrupo C na faixa etária vacinada e o sorogrupo W se destacou. Conclusão: A partir do início desse século houve declínio expressivo da incidência da DMI nas capitais da região Sul do país, antes mesmo da introdução da vacina, aproximando-se das taxas de DMI encontradas em países de elevada renda. Tais resultados são consistentes, com trabalhos que mostram uma associação da DMI com as condições de vida e grau de desenvolvimento das populações

Objectives: To analyze the trend and describe changes in the epidemiology of invasive meningococcal disease (IMD) and to estimate the impact of the meningococcal conjugate C vaccine (MCCV) in the capitals of the southern region of Brazil, from 1991 to 2015, as well as to investigate the sociodemographic, economic and technological interventions associated to the cases belonging in cluster of the disease in the city of Curitiba (PR), from 2001 to 2014. Methods: The study areas included the capitals of the States of Southern Brazil: Curitiba (PR), Florianópolis (SC) and Porto Alegre (RS), the study population considered cases of IMD reported between 1991 and 2015 to surveillance and residents in these capitals. The IMD case definition adopted was that standardized by the Ministry of Health. The data sources were the surveillance of the IMD, the Adolfo Lutz Institute, the Brazilian Institute of Geography and Statistics and the Institute of Research and Urban Planning of Curitiba. The trend of IMD incidence and mortality was determined by the polynomial regression model. The intensity and direction of the linear relationship between the incidence rate and socioeconomic indicators, health and serogroup were analyzed by the Pearson correlation coefficient. The impact of the MCCV was estimated by the Prevented Fraction for the Population comparing the incidence rates of 2012 and 2015 with those of 2009. We investigated the potential factors associated with cases belonging in cluster between 2001 and 2014 by the unadjusted and adjusted odds ratio estimates by the multiple unconditional logistic regression, with the respectives confidence intervals of 95%. Results: Between 1991 and 2015, IMD presented three distinct periods in the capitals of the southern region: i) epidemic in the 1990s, ii) decline in rates from 2000 to 2010, before the introduction of MCCV in immunization routine and (iii) stationary at low rates in 2011 to 2015, under the influence of MCCV. In this period, we observed the influence of biological, socioeconomic and health factors on the incidence of these capitals. In more detailed study in Curitiba, it was associated with cases belonging in cluster, adjusted in time and by age, to live in low-income neighborhoods (OR: 2.3, 95% CI: 1.1-4.5). Serogroup B was predominant with 65,4%, followed by C with 24,5% and 8,3% by W. Possibly, due to the low incidence of serogroup C, there was no reduction in the total incidence of IMD in these capitals. However, *in the period after MCCV, serogroup C cases were rare or zero in the age group destinedfor vaccination in Curitiba and Florianópolis. In Porto Alegre, cases were registered by serogroup C in the vaccinated age group and serogroup W was relevant. Conclusion: From the beginning of this century there was a significant decline in the incidence of IMD in the capitals of the southern region of the country, even before the introduction of the vaccine, approaching IMD rates found in high income countries. These results are consistent, with studies showing an association of IMD with living conditions and the degree of population development

Actualización sobre enfermedad meningocócica y su prevención / Update on meningococcal disease and its prevention

En Argentina la enfermedad meningocócica (EM) tiene un comportamiento endemo-epidémico y los niños <5 años son los más afectados, la letalidad es del 10%, con mayor impacto en <1 año. Históricamente los serogrupos predominantes fueron B y C y en la actualidad prevalecen los serogrupos W y B. En 2017 Argentina incorporó la vacunación meningocócica (Resolución 10/2015) con un esquema de 2+1 (3 meses-5 meses-15/18 meses) de la vacuna conjugada cuadrivalente ACWY-CRM197-Menveo®. La estrategia incluye una única dosis de vacuna a los 11 años, con el objetivo de disminuir la portación orofaríngea y así contribuir a la disminución de la incidencia de EM en el grupo más vulnerable. El programa también provee la vacunación para huéspedes especiales. También se encuentran disponibles la vacuna cuadrivalente ACWY conjugada con toxoide diftérico (MenACYW-D)-Menactra®, licenciada para niños ≥9 meses hasta los 55 años, y la vacuna meningocócica B multicomponente recombinante (MenB-4C)-Bexsero®. Esta última aprobada en 2015 para su uso en ≥2 meses de vida. Estudios post licencia demostraron un alto nivel de protección y de seguridad de la vacuna. Es por el momento una vacuna de indicación individual que se está analizando en la esfera de Salud Pública

Meningococcal disease (MD) is endemoepidemic in Argentina, where most cases occur in children <5 years of age, and the fatality rate is 10% with the highest impact among infants <1 year of age. Historically, the predominant serogroups were B and C, and the serogroups W and B prevail at present. In 2017, the meningococcal vaccine was introduced in the Argentine National Immunization Program with a two-dose plus a booster schedule (3 months-5 months-15/18 months) of the quadrivalent meningococcal conjugate vaccine MenACWY-CRM197 (Menveo®). The strategy includes a single dose of the vaccine at 11 years of age, with the aim of reducing oropharyngeal carriage, thus contributing to the reduction of the MD incidence in the most vulnerable group. The program also provides vaccination for special hosts. There are also other vaccines available privately, such as the quadrivalent meningococcal conjugate vaccine MenACWY-D (Menactra®), licensed for children ≥9 months of age up to 55 years of age, and the multicomponent meningococcal serogroup B vaccine 4CMenB (Bexsero®). This vaccine was approved in 2015 for use in ≥2 months of age. Post-license studies demonstrated its strong protection and safety. It is, for the time being, a vaccine of individual indication that is being analyzed in the Public Health area