Epidemiological burden of meningococcal disease in Latin America: A systematic literature review

Genetic characterization and estimated 4CMenB vaccine strain coverage of 284 Neisseria meningitidis isolates causing invasive meningococcal disease in Argentina in 2010-2014

Meningococcal (Neisseria meningitidis) serogroup B (MenB) strain antigens are diverse and a limited number of strains can be evaluated using the human serum bactericidal antibody (hSBA) assay. The genetic Meningococcal Antigen Typing System (gMATS) was developed to predict the likelihood of coverage for large numbers of isolates by the 4CMenB vaccine, which includes antigens Neisseria adhesin A (NadA), Neisserial Heparin-Binding Antigen (NHBA), factor H-binding protein (fHbp), and Porin A (PorA). In this study, we characterized by whole-genome analyses 284 invasive MenB isolates collected from 2010 to 2014 by the Argentinian National Laboratories Network (52-61 isolates per year). Strain coverage was estimated by gMATS on all isolates and by hSBA assay on 74 randomly selected isolates, representative of the whole panel. The four most common clonal complexes (CCs), accounting for 81.3% of isolates, were CC-865 (75 isolates, 26.4%), CC-32 (59, 20.8%), CC-35 (59, 20.8%), and CC-41/44 (38, 13.4%). Vaccine antigen genotyping showed diversity. The most prevalent variants/peptides were fHbp variant 2, NHBA peptides 24, 21, and 2, and PorA variable region 2 profiles 16-36 and 14. The nadA gene was present in 66 (23.2%) isolates. Estimated strain coverage by hSBA assay showed 78.4% of isolates were killed by pooled adolescent sera, and 51.4% and 64.9% (based on two different thresholds) were killed by pooled infant sera. Estimated coverage by gMATS (61.3%; prediction interval: 55.5%, 66.7%) was consistent with the infant hSBA assay results. Continued genomic surveillance is needed to evaluate the persistence of major MenB CCs in Argentina.

Epidemiology of Meningococcal Disease in Four South American Countries and Rationale of Vaccination in Adolescents from the Region: Position Paper of the Latin American Society of Pediatric Infectious Diseases (SLIPE)

Surveillance of meningococcal disease (MD) is crucial after the implementation of vaccination strategies to monitor their impact on disease burden. Adolescent vaccination could provide direct and indirect protection. Argentina, Brazil, and Chile have introduced meningococcal conjugate vaccines (MCV) into their National Immunization Programs (NIP), while Uruguay has not. Here, we analyze the epidemiology of MD and vaccination experience from these four South American countries to identify needs and plans to improve the current vaccination programs.

METHODOLOGY

Descriptive study of MD incidence rates, serogroup distribution, case fatality rates (CFR), and MCV uptakes during the period 2010-2021 in Argentina, Brazil, Chile, and Uruguay. Data were extracted from national surveillance programs, reference laboratories, NIPs, and Pubmed.

RESULTS

MD overall incidence from 2010 to 2021 have a decreasing trend in Argentina (0.37 [IQR = 0.20-0.61]), Brazil (0.59 [IQR = 0.54-1.22]), and Chile (0.45 [IQR = 0.40-0.77]), while a significant increase in Uruguay (0.47 [IQR = 0.33-0.69]) was found from 2016 to 2019. During the COVID-19 pandemic, all countries sharply reduced their MD incidence. The highest incidence rates were observed among infants, followed by children 1-4 years of age. No second peak was evident in adolescents. A reduction in serogroup C, W, and Y cases has occurred in Argentina, Brazil, and Chile after introduction of MCV, serogroup B becoming predominant in all four countries. Median CFR was 9.0%, 21%, 19.9%, and 17.9% in Argentina, Brazil, Chile, and Uruguay, respectively. Median uptake of MCV for Argentina and Brazil were 66.6% and 91.0% for priming in infants; 54.7% and 84.5% for booster in toddlers; and 47.5% and 53% for adolescents; while for Chile, 95.6% for toddlers.

CONCLUSIONS

Experience after the implementation of MCV programs in South America was successful, reducing the burden of MD due to the vaccine serogroups. High vaccine uptake and the inclusion of adolescents will be crucial in the post-pandemic period to maintain the protection of the population. The increase in the proportion of serogroup B cases emphasizes the importance of continuous surveillance to guide future vaccination strategies.

Meningococcal burden of disease in Argentina: 10 years epidemiologic review

Invasive meningococcal disease (IMD) is an uncommon but serious and potentially fatal condition, mainly affecting infants. In 2017, Argentina introduced a vaccination program against serogroups A, C, W and Y (MenACWY) for infants aged 3, 5 and 15 months and adolescents aged 11 years. The objective of this study was to review the burden of IMD in Argentina in 2010-2019. Data were obtained from national surveillance databases, and the study estimated IMD incidence, mortality, case-fatality rates, and serogroup distributions across age groups. A total of 1,972 IMD cases were reported in the study period, with the highest incidence in infants aged < 1 year. Incidence peaked in 2013 and subsequently declined. Mortality rates were 18 times higher in infants than in other age groups, reflecting the high impact of IMD in this age group. The case-fatality rate was 8.5% on average and increased with age. The proportion of notified cases with serogroup identification increased over the period, reaching 91% in 2019. The most common serogroups over the study period were serogroup B (48%) and serogroup W (42%), with an increase in B relative to W since 2015. In infants aged < 1 year, the proportion of serogroup B increased in recent years, reaching around 70% of characterized cases in 2018-2019. These results show the dynamism of IMD and indicate the importance of vaccination at an early age and offering protection against predominant serogroups. These data are valuable to support evidence-based decision-making in healthcare.

Surveillance of invasive meningococcal disease in southern Brazil: considerations of an immunization programme

Invasive meningococcal disease (IMD) is a major cause of meningitis and septicaemia worldwide. Changes in serogroup predominance contribute to the unpredictable nature of the disease, with significant health impact. This study aimed to determine the epidemiological profile of IMD in Rio Grande do Sul, Santa Catarina and Paraná, three states in southern Brazil. We analysed 1024 IMD cases that had been confirmed by clinical and/or laboratory criteria and reported to the national information system for notifiable diseases between 2015 and 2019. Additionally, we calculated the proportions of serogroup and incidence by age. Of 1024 cases, 562 (55 %) were caused by serogroup C. Furthermore, serogroup W was responsible for almost half of the cases among children younger than 5 years between 2017 and 2018, with an overall incidence of 1.5 cases/100 000 infants. IMD remains a significant healthcare issue in southern Brazil despite reduced serogroup C incidence after the introduction of the meningococcal C conjugate vaccine into the childhood immunization programme. Changes in disease epidemiology were observed, and serogroup W was the most common serogroup among children younger than 5 years in 2017 and 2018. Although future cost-effectiveness studies are necessary, our results could have future implications for meningococcal vaccination programmes.

Comprehensive Genome Analysis of Neisseria meningitidis from South America Reveals a Distinctive Pathogenicity-Related Prophage Repertoire

Neisseria meningitidis, a bacterium that colonizes in the human nasopharynx, occasionally causes invasive meningococcal disease leading to meningitis or septicemia. Different serogroups and lineages (clonal complexes) are related to the occurrence and epidemiology of N. meningitidis. Despite vaccines for most serogroups, N. meningitidis lineages causing unusual clinical manifestations and a higher fatality rate compared to other lineages have been reported in South America. The present study focused on exploring the diversity of N. meningitidis prophages from South America and their relationship with the epidemiological variables of these strains. We found a high diversity of prophages among the different clonal complexes. By comparing them with previously described N. meningitidis phages and prophages, we revealed groups of prophages sharing similar compositions, which could be useful for prophage comparison in N. meningitidis. Furthermore, we observed a high correlation between the prophage content and epidemiological features, e.g., pathogenicity or clonal complex. Additionally, a distinctive filamentous prophage named here as IMSAR-11 (Invasive Meningococci from South America Related to cc11) was identified. Interestingly, two versions of IMSAR-11, circular and chromosomally integrated, were found. Overall, this study reinforces the importance of the genomic characterization of circulating N. meningitidis lineages to generate new targets for lineage monitoring, diagnosis, or appropriateness of vaccine development. Further studies are necessary to understand the role of these prophages in the persistence, dispersal, and virulence of N. meningitidis in the world.

Economic burden of meningococcal disease in children and adolescents in Tijuana, Mexico

Invasive meningococcal disease (IMD) is an uncommon but serious and potentially fatal condition mainly affecting children and adolescents. Active surveillance between 2005 and 2016 at Tijuana General Hospital, Mexico, indicated that the incidence of IMD in Tijuana was higher than previously thought, at 2.69 per 100,000 population aged <16 years. The objective of this study was to estimate the economic burden associated with 51 IMD cases in children aged <16 years identified over the 11 years of active surveillance at Tijuana General Hospital, Mexico. Healthcare resource usage for the IMD cases was obtained from the hospital database and combined with unit costs from the hospital purchasing department or national databases to estimate total healthcare costs over a follow-up period of 3 months. Societal costs were represented by the value of lost wages for parents or guardians. All costs were expressed in US$. Over the 11-year study period there were 51 IMD cases, of which 13 (25%) were fatal. The total cost for all 51 cases over the 11-year study period was US$1,054,499 (average per case US$20,676), of which direct healthcare costs comprised US$1,029,948 (average per case US$20,195) and societal costs US$24,551 (average per case US$481). Extrapolated to the population of Tijuana region aged <16 years, the estimated annual economic burden of IMD was US$268,794. The major cost driver was the cost of hospitalization. These data illustrate the significant economic burden associated with IMD in Tijuana, and will be useful in assessing optimal vaccination programs against meningococcal disease in Mexico.

Sequelae at Hospital Discharge in 61 Children With Invasive Meningococcal Disease, Chile, 2009-2019

BACKGROUND

Invasive meningococcal disease (IMD) is an unpredictable and severe infection caused by Neisseria meningitidis . Its case fatality rate could vary from 9.7% to 26% and up to 36% of survivors may experience long-term sequelae, representing a challenge for public health.

AIMED

To describe the sequelae at hospital discharge caused by IMD in children between years 2009-2019.

METHODS

Cross-sectional study performed in 2 pediatric hospitals. Patients with microbiologically confirmed diagnosis of IMD from 2009 to 2019 were included. Bivariate and logistic regression analysis were performed.

RESULTS

The records of 61 patients were reviewed and included. Sixty-seven percent were male, median age 9 months (interquartile range 4-27), 72% were admitted to intensive care unit. Thirty-seven (60.5%) had at least 1 sequela (75% and 37% in patients with or without meningitis, respectively). The most frequents sequelae were neurological 72%, hearing loss 32%, and osteoarticular 24%. Significant differences were found comparing patients with and without sequelae: drowsiness 67.6% versus 41.7% ( P = 0.04), irritability 67.6% versus 25% ( P = 0.01), meningeal signs 62.2% versus 29.2% ( P = 0.01). In logistic regression analysis, postdischarge follow-up had OR 21.25 (95% confidence intervals [CI]: 4.93-91.44), irritability had OR 8.53 (95% CI: 1.64-44.12), meningeal signs had OR 8.21 (95% CI: 0.71-94.05), invasive mechanical ventilation had OR 8.23 (95% CI: 0.78-85.95), meningitis plus meningococcemia OR 1.70 (95% CI: 0.18-15.67) to have sequelae, while children with meningococcemia and vomiting had a OR 0.04 (95% CI: 0.00-0.36) and OR 0.27 (95% CI: 0.03-2.14), respectively. N. meningitidis serogroup W (MenW) was isolated in 54.1% (33/61), and N. meningitidis serogroup B (MenB) in 31.1% (19/61) of cases. A significant difference was found in osteoarticular sequelae ( P = 0.05) between MenB and MenW. There was a decrease in cases after the meningococcal conjugate vaccine against serogroups A, C, W and Y was implemented (2015-2019).

CONCLUSIONS

IMD remains as a public health concern. A high rate of sequelae was found in pediatric patients in our series, even in the clinical manifestations other than meningitis. Neurological sequelae were the most prevalent. Multidisciplinary follow-up protocols to reduce long-term impact must be urgently established to assess all children with IMD.

Identification of the nasopharyngeal carriage of Neisseria meningitidis by 16S rRNA Gene sequencing in asymptomatic adolescents and young adults in Cartagena, Colombia (2019–2020)

The bacterium Neisseria meningitidis, a strictly human pathogen, can cause meningitis, meningococcemia, sepsis, and death; repeatedly it scause outbreaks around the world. The frequency of asymptomatic carriage is often high in adolescents and young adults, increasing the invasive meningococcal disease risk and likelihood of transmission. However, detailed analyses of meningococcal carriage in this population in Colombia, particularly in coastal areas, are lacking. In this study, the prevalence and characteristics of Neisseria meningitidis carriage were evaluated in asymptomatic adolescents and young adults (11-25 years old) in Cartagena, Colombia. Oropharynx samples were collected from participants between August and December 2019. The phenotypic identification of bacteria was performed by conventional methods and biochemical testing. Molecular identification to the species level was performed by 16S rRNA gene sequencing. In total, 12 of 648 samples were positive for Neisseria meningitidis by 16S rRNA sequencing, indicating a prevalence of 1.9%. Isolates were classified into four invasive serogroups (A, B, C, and W) by a comparative sequence analysis of the ribosomal gene. Despite the occurrence of meningococcal disease in Cartagena city in the last several years, the frequency of oropharyngeal carriage in adolescents and young adults was low. Serogroup A had not been previously reported in nasopharyngeal samples in Colombia. This is the first report of Neisseria meningitidis on the Colombian Caribbean coast based on 16S rRNA sequencing and is expected to guide the development of vaccination and follow-up strategies.

Burden of epilepsy in Latin America and The Caribbean: a trend analysis of the Global Burden of Disease Study 1990 - 2019

Background

The epilepsy prevalence in Latin America and the Caribbean (LAC) had remained high over the last 20 years. Data on the burden of epilepsy are needed for healthcare planning and resource allocation. However, no systematic analysis had been performed for epilepsy burden in LAC.

Methods

We extracted data of all LAC countries from the Global Burden of Disease (GBD) study from 1990 to 2019. Epilepsy burden was measured as prevalence, mortality, and disability-adjusted life-years (DALYs; defined by the sum of years of life lost [YLLs] for premature mortality and years lived with disability [YLDs]), by age, sex, year, and country. Absolute numbers, rates, and 95% uncertainty intervals were reported. We performed correlational analyses among burden metrics and Socio-demographic Index (SDI).

Findings

The burden of epilepsy decreased around 20% in LAC, led by YLLs reduction. In 2019, 6·3 million people were living with active epilepsy of all causes (95% UI 5·3 - 7·4), with 3·22 million (95% UI 2·21 - 4·03) and 3·11 million (95% UI 2·21 to 4·03) cases of epilepsy with identifiable aetiology and idiopathic epilepsy, respectively. The number of DALYs represented the 9·51% (1.37 million, 95% UI 0·99 -1·86) of the global epilepsy burden in 2019. The age-standardized burden was 175·9 per 100 000 population (95% UI 119·4 - 253·3), which tend to have a bimodal age distribution (higher in the youth and elderly) and was driven by high YLDs estimates. The burden was higher in men and older adults, primarily due to high YLLs and mortality. Alcohol use was associated with 17% of the reported DALYs. The SDI estimates significantly influenced this burden (countries with high SDI have less epilepsy burden and mortality, but not prevalence or disability).

Interpretation

The epilepsy burden has decreased in LAC over the past 30 years. Even though, LAC is still ranked as the third region with the highest global epilepsy burden. This reduction was higher in children, but burden and mortality increased for older adults. The epilepsy burden is disability predominant; however, the mortality-related estimates are still higher than in other regions. Alcohol consumption and countries' development are important determinants of this burden. There is an urgent need to improve access to epilepsy care in LAC, particularly for older adults. Strengthening primary care with online learning and telemedicine tools, and promoting risk factors modification should be prioritized in the region.

Funding

This research was self-funded by the authors.

Modeling the public health impact of different meningococcal vaccination strategies with 4CMenB and MenACWY versus the current toddler MenACWY National Immunization Program in Chile

Invasive meningococcal disease (IMD) is an uncommon yet unpredictable, severe, and life-threatening disease with the highest burden in young children. In Chile, most IMD is caused by meningococcal serogroup B (MenB) and W (MenW) infection. In response to a MenW outbreak in 2012, a toddler vaccination program was implemented using quadrivalent meningococcal conjugate vaccine against serogroups A, C, W and Y (MenACWY). The vaccine program, however, does not protect infants or other unvaccinated age groups and does not protect against MenB IMD. Since 2017, MenB IMD cases are becoming increasingly prevalent. Using a dynamic transmission model adapted for Chile, this analysis assessed the public health impact (reduction in IMD cases, long-term sequelae, deaths, and quality-adjusted life-years) of six alternative vaccination strategies using MenACWY and/or the four-component MenB (4CMenB) vaccine in infants, toddlers, and/or adolescents compared to the National Immunization Program (NIP) implemented in 2014. Strategies that added infant 4CMenB to MenACWY in toddlers or adolescents would prevent more IMD than the current NIP, observed within the first 5 years of the program. Replacing the NIP by an adolescent MenACWY strategy would prevent more IMD in the longer term, once herd immunity is established to protect unvaccinated infants or older age groups. The strategy that maximized reduction of IMD cases and associated sequelae in all age groups with immediate plus long-term benefits included infant 4CMenB and MenACWY in both toddlers and adolescents. This analysis can help policymakers determine the best strategy to control IMD in Chile and improve public health. A set of audio slides linked to this manuscript can be found at https://doi.org/10.6084/m9.figshare.16837543.

What is the context?

Invasive meningococcal disease (IMD) is a severe, sometimes fatal, unpredictable disease with highest rates in infants, young children, and adolescents. It is caused by different serogroups of Neisseria meningitidis bacteria. Most cases in Chile are due to meningococcal serogroups B (MenB) and W (MenW). Following a MenW IMD outbreak in 2012, vaccination was introduced, leading to the current National Immunization Program (NIP) in toddlers with quadrivalent meningococcal conjugate vaccine (MenACWY) (protecting against IMD caused by MenA, C, W, and Y).

What is new?

A disease model to predict the impact of vaccination strategies in the Chilean population compared six alternative strategies, using the multi-component MenB (4CMenB) vaccine for infants (protecting against MenB, with potential cross-protection against MenW and Y IMD) and/or the MenACWY vaccine for toddlers and/or adolescents.

What is the impact?

Results, compared to the NIP, show that: Strategy 1 (a program targeting only infants with 4CMenB) would reduce more MenB cases but fewer MenA, C, W and Y cases resulting in a lower reduction of total IMD cases in the long term; Strategy 3 (a program targeting only adolescents with MenACWY) would have a similar effect to the NIP in the short term but a far greater IMD reduction in the long term (as vaccinating this age group eventually reduces transmission to other age groups, reducing their risk of disease); all the other strategies targeted more than one age group, further reducing numbers of IMD cases compared with the NIP. The greatest benefits were seen with infant 4CMenB vaccination combined with toddler and adolescent MenACWY vaccination. Results can help policymakers determine the best IMD strategy to maximize the benefits of available meningococcal vaccines.

Systematic review of invasive meningococcal disease epidemiology in the Eastern Mediterranean and North Africa region

BACKGROUND

Invasive meningococcal disease (IMD) represents a global health burden. However, its epidemiology in the Eastern Mediterranean (EM) and North Africa (NA) regions is currently not well understood. This review had four key objectives: to describe asymptomatic meningococcal carriage, IMD epidemiology (e.g. serogroup prevalence, case-fatality rates [CFRs]), IMD presentation and management (e.g. clinical diagnosis, antibiotic treatments) and economic impact and evaluation (including health technology assessment [HTA] recommendations) in EM and NA.

METHODS

A systematic literature search (MEDLINE and EMBASE) was conducted (January 2000 to February 2021). Search strings included meningococcal disease and the regions/countries of interest. Identified publications were screened sequentially by title/abstract, followed by screening of the full-text article; articles were also assessed on methodological quality. Literature reviews, genetic sequencing or diagnostic accuracy studies, or other non-pertinent publication type were excluded. An additional grey literature search (non-peer-reviewed sources; start date January 2000) was conducted to the end of April 2019.

RESULTS

Of the 1745 publications identified, 79 were eligible for the final analysis (n = 61 for EM and n = 19 for NA; one study was relevant to both). Asymptomatic meningococcal carriage rates were 0-33% in risk groups (e.g. military personnel, pilgrims) in EM (no data in NA). In terms of epidemiology, serogroups A, B and W were most prevalent in EM compared with serogroups B and C in NA. IMD incidence was 0-20.5/100,000 in EM and 0.1-3.75/100,000 in NA (reported by 7/15 countries in EM and 3/5 countries in NA). CFRs were heterogenous across the EM, ranging from 0 to 57.9%, but were generally lower than 50%. Limited NA data showed a CFR of 0-50%. Data were also limited in terms of IMD presentation and management, particularly relating to clinical diagnosis/antibiotic treatment. No economic evaluation or HTA studies were found.

CONCLUSIONS

High-risk groups remain a significant reservoir of asymptomatic meningococcal carriage. It is probable that inadequacies in national surveillance systems have contributed to the gaps identified. There is consequently a pressing need to improve national surveillance systems in order to estimate the true burden of IMD and guide appropriate prevention and control programmes in these regions.

The Impact of Haemophilus Influenzae and Streptococcus Pneumoniae Vaccination in Bacterial Meningitis in a Pediatric Referral Hospital in Mexico

Objective This study aimed to compare the epidemiology of bacterial meningitis (BM) before and after vaccination, and identify possible risk factors associated with mortality.

Methods The medical and microbiologic records of children (1 month–18 years) with a discharge diagnosis of BM in a third level children's hospital in Mexico from 1990 to 2018 were reviewed. The epidemiology, pathogens, and outcomes were compared before and after introducing Haemophilus influenzae type b (Hib) and pneumococcal conjugate vaccines to the Mexican immunization schedule. Risk factors associated with mortality were determined.

Results In the 28-year period, 226 cases with BM were included 55.8% (1990–1999), 27.4% (2000–2008), and 16.8% (2009–2018) (p = 0.0001). The most frequent pathogen was Hib, documented in 39% of cases. There was a reduction in neurological complications after introducing the Hib conjugate vaccine (59 vs. 39%; p = 0.003) and sequelae after the Streptococcus pneumoniae conjugate vaccine (43 vs. 35%; p = 0.05). Independent risk factors associated with mortality were coma (odds ratio [OR]: 15 [2.9–78]), intracerebral bleeding (OR: 3.5 [1.4–12]), and pneumococcal meningitis (OR: 9.4 [2.2–39]).

Conclusion Since the introduction of Hib and pneumococcal conjugate vaccines to the national immunization schedule, there was a reduction in BM cases, mainly associated with the Hib vaccine, with the consequent reduction of neurological complications and sequelae.

Immunogenicity and safety of a quadrivalent meningococcal tetanus toxoid-conjugate vaccine administered concomitantly with other paediatric vaccines in toddlers: a phase III randomised study

Invasive meningococcal disease has high morbidity and mortality, with infants and young children among those at greatest risk. This phase III, open-label, randomised study in toddlers aged 12-23 months evaluated the immunogenicity and safety of meningococcal tetanus toxoid-conjugate vaccine (MenACYW-TT), a tetanus toxoid conjugated vaccine against meningococcal serogroups A, C, W and Y, when coadministered with paediatric vaccines (measles, mumps and rubella [MMR]; varicella [V]; 6-in-1 combination vaccine against diphtheria, tetanus, pertussis, polio, hepatitis B and Haemophilus influenzae type b [DTaP-IPV-HepB-Hib] and pneumococcal conjugate vaccine [PCV13])(NCT03205371). Immunogenicity to each meningococcal serogroup was assessed by serum bactericidal antibody assay using human complement (hSBA). Vaccine safety profiles were described up to 30 days post-vaccination. A total of 1183 participants were enrolled. The proportion with seroprotection (hSBA ≥1:8) to each meningococcal serogroup at Day 30 was comparable between the MenACYW-TT and MenACYW-TT + MMR + V groups (≥92 and ≥96%, respectively), between the MenACYW-TT and MenACYW-TT + DTaP-IPV-HepB-Hib groups (≥90% for both) and between the MenACYW-TT and MenACYW-TT + PCV13 groups (≥91 and ≥84%, respectively). The safety profiles of MenACYW-TT, and MMR + V, DTaP-IPV-HepB-Hib, and PCV13, with or without MenACYW-TT, were generally comparable. Coadministration of MenACYW-TT with paediatric vaccines in toddlers had no clinically relevant effect on the immunogenicity and safety of any of the vaccines.

Surveillance of invasive meningococcal disease in the south of Brazil: considerations of immunization programme

Invasive meningococcal disease (IMD) is a major cause of meningitis and septicaemia worldwide. The switches in serogroup predominance contribute to the unpredictable nature of the disease with significant health impacts. The aim of this study was to determine the epidemiological profile of IMD in Rio Grande do Sul, Santa Catarina and Paraná, three states in the south of Brazil. All meningitis cases confirmed by clinical and/or laboratory criteria notified to the national information system for notifiable diseases between 2015 and 2019 were analysed. Proportions of serogroup and incidence by age were calculated. A total of 17 894 cases of IMD were reported during this period. Of these, 9029 cases (50 %) were due to serogroup C. Furthermore, serogroup W was responsible for almost half of the cases among children younger than 5 years old during 2017 and 2018, with an overall incidence of 33.3 cases per 100 000 infants. Despite the reduction in serogroup C after the introduction of meningococcal C conjugate vaccine into a childhood immunization programme in Brazil, it remains a significant healthcare issue in the south of the country. Changes in disease epidemiology were observed and serogroup W was the most common among children below 5 years of age in 2017 and 2018. Although future cost-effectiveness studies are necessary, our results could have future implications for meningococcal vaccination programmes.

Epidemiological profile of Neisseria meningitidis in Casablanca, Morocco: 2010-2019

Surveillance of invasive meningococcal diseases (IMD) must be carried out regularly and continuously in order to detect the emergence of strains of reduced susceptibility to antibiotics for therapeutic and prophylactic use and the appearance of new invasive clones. Molecular-typing approaches allow reliable traceability and powerful epidemiological analysis. This is an epidemiological study of Neisseria meningitidis causing meningitis in Casablanca, Morocco. The grouping was confirmed by PCR mainly on the isolates from cerebrospinal fluid (CSF). A total of 245 confirmed isolates of N .meningitidis were obtained between 2010 and 2019 of which 93 % are of group B. Overall, 24 % of all the isolates have a reduced susceptibility to penicillin G, but no resistance to penicillin G has been reported. All the isolated strains are susceptible to third-generation cephalosporins (3GCs). Genotyping by multilocus sequence typing (MLST) of a selection of 18 strains showed that the majority of isolates belong to the invasive clonal complex CC 32(9/18) followed by the CC 41/44(3/18).

Invasive meningococcal disease in Italy: from analysis of national data to an evidence-based vaccination strategy

Introduction

Invasive meningococcal disease (IMD) is one of the most severe vaccine-preventable disease not yet under control. In Italy, although different anti-meningococcal vaccines are available, their offer among regions is heterogeneous. The aim of this study is to describe the epidemiology of IMD in Italy based on analysis of national surveillance data for 2011-2017 to optimize the vaccination strategy.

Methods

IMD surveillance data from the Italian National Health Institute were analysed. Microsoft Excel was used to present trend analysis, stratifying by age and serogroups.

Results

In Italy, during the period 2011-2017, the incidence of IMD increased from 0.25 cases/100,000 inhabitants in 2011 to 0.33 cases/100,000 in 2017. Most cases after 2012 were caused by non-B serogroups. The number of cases in subjects aged 25-64 years increased steadily after 2012 (36 cases in 2011, 79 in 2017), mostly due to non-B serogroups, representing more than 65% of cases in those aged 25+ years.

Conclusions

In the period from 2011 to 2017, the incidence of IMDs increased in Italy. The increase, probably due also to a better surveillance, highlights the importance of the disease in the adult population and the high level of circulation of non-B serogroups in particular after 2012. Our analysis supports an anti-meningococcal vaccination plan in Italy that should include the highest number of preventable serogroups and be aimed at vaccinating a wider population through a multicohort strategy.

The everchanging epidemiology of meningococcal disease worldwide and the potential for prevention through vaccination

Neisseria meningitidis is a major cause of bacterial meningitis and septicaemia worldwide and is associated with high case fatality rates and serious life-long complications among survivors. Twelve serogroups are recognised, of which six (A, B, C, W, X and Y) are responsible for nearly all cases of invasive meningococcal disease (IMD). The incidence of IMD and responsible serogroups vary widely both geographically and over time. For the first time, effective vaccines against all these serogroups are available or nearing licensure. Over the past two decades, IMD incidence has been declining across most parts of the world through a combination of successful meningococcal immunisation programmes and secular trends. The introduction of meningococcal C conjugate vaccines in the early 2000s was associated with rapid declines in meningococcal C disease, whilst implementation of a meningococcal A conjugate vaccine across the African meningitis belt led to near-elimination of meningococcal A disease. Consequently, other serogroups have become more important causes of IMD. In particular, the emergence of a hypervirulent meningococcal group W clone has led many countries to shift from monovalent meningococcal C to quadrivalent ACWY conjugate vaccines in their national immunisation programmes. Additionally, the recent licensure of two protein-based, broad-spectrum meningococcal B vaccines finally provides protection against the most common group responsible for childhood IMD across Europe and Australia. This review describes global IMD epidemiology across each continent and trends over time, the serogroups responsible for IMD, the impact of meningococcal immunisation programmes and future needs to eliminate this devastating disease.

A critical analysis of serogroup B meningococcal disease burden in Brazil (2001-2015): implications for public health decisions

The recent licensure of two different serogroup B recombinant protein meningococcal vaccines in Brazil emphasizes the importance of a better knowledge of the real burden of serogroup B meningococcal (MenB) disease to establish evidence-based vaccination policies. We performed an observational, descriptive study, from 2001 to 2015, analyzing the incidence and case fatality rates (CFR) of MenB disease in Brazil, according to age group and region. In the absence of any vaccine use targeting MenB disease, a significant decline of 90% in the overall incidence rates of MenB disease was observed (from 0.55 cases/100,000 habitants in 2001 to 0.05 in 2015), with declines found in all age groups during the study period. The highest incidence rates were consistently observed in infants and children 1-4 year of age, whereas adults ≥ 60 years experienced the highest CFR (33.9%). The proportion of cases with serogroup identified increased from 37.1% in 2001 to 51.5% in 2015. Despite an improvement in recent years, the quality of diagnosis is highly heterogeneous in the diverse regions, presenting important deficiencies that still prevent the possibility of a robust and reliable analysis of the burden of the meningococcal disease in Brazil. Based on the findings of this study and taking in account the unlikely indirect effect associated with the use of the new recombinant serogroup B protein vaccines, infants < 1 year is the age group to be prioritized when considering the implementation of routine immunization programmes with MenB vaccines.