Recent advances in meningococcal B disease prevention: real-world evidence from 4CMenB vaccination

Factors influencing vaccine hesitancy among United Kingdom adolescents in a senior high school environment and actions to address it

We explored adolescent viewpoints on vaccines and hesitancy using an anonymized, validated, self-completed electronic questionnaire amongst state-school Year 12-13 adolescents in London, UK. As the response rate was low (Cohort 1; n = 112/486, 23.0%), we repeated the survey with incoming students (cohort 2, n = 256/275; 93%). A focus group (n = 31) evaluated international HPV campaign posters. Cohort 1 participants were 82.1% female, 13.4% male, and ethnically diverse (32.1% Asian/Asian British, 29.5% Black/Black British, 25.9% White, 7.1% Mixed); Cohort 2 were 80% female, 18% male, with participants identifying as 38% Black/Black British, 34% Asian/Asian British, 15% White, 12% Mixed/Others. Across both cohorts, participants believed childhood vaccinations were safe (Cohort 1 = 95.8%, Cohort 2 = 91%). COVID-19 vaccination uptake was higher in Cohort 1 than 2 (76.8% vs 67%), with fewer participants believing it was adequately tested (56.3% vs 47%). Support for mandatory COVID-19 vaccination for healthcare workers (HCW) was high (Cohort 1:77.8-79% "all" vs "patient-facing HCWs;" Cohort 2 = 62-64%). Similar patterns were observed for mandatory influenza vaccination (Cohort 1: 62.5-66.7%; Cohort 2: 62-63%). Vaccination decisions in Cohort 2 were primarily influenced by parents (96%), healthcare providers (48%), and school friends (36%) (Cohort 1 = 30.2%, 19.6%, and 12%, respectively). Recommendations by doctors, experts and parents (but not politicians) and school-based vaccine availability boosted vaccine confidence. Social media had minimal impact. Most participants received HPV vaccine (Cohort 1 = 83.1%, Cohort 2 = 77.2%). International HPV posters received strong but mixed support; direct design input from the target group is needed to ensure the success of visual vaccine promotions.

Breadth of immune response, immunogenicity, reactogenicity, and safety for a pentavalent meningococcal ABCWY vaccine in healthy adolescents and young adults: results from a phase 3, randomised, controlled observer-blinded trial

BACKGROUND

A multicomponent meningococcal serogroups ABCWY vaccine (MenABCWY) could provide broad protection against disease-causing meningococcal strains and simplify the immunisation schedule. The aim of this trial was to confirm the effect of the licensed meningococcal serogroup B (MenB) vaccine, 4CMenB, against diverse MenB strains, and to assess the breadth of immune response against a panel of 110 MenB strains for MenABCWY containing the antigenic components of 4CMenB and licensed serogroups ACWY vaccine, MenACWY-CRM, the non-inferiority of the immune response with MenABCWY versus 4CMenB and MenACWY-CRM, safety, and MenABCWY lot-to-lot consistency.

METHODS

We conducted a phase 3 randomised, controlled, observer-blinded trial of healthy adolescents and young adults (age 10-25 years) across 114 centres in Australia, Canada, Czechia, Estonia, Finland, Türkiye, and the USA. Exclusion criteria included previous vaccination with a MenB vaccine or (within the last 4 years) MenACWY vaccine. Participants were randomly allocated (5:5:3:3:3:1 ratio) via a central randomisation system using a minimisation procedure to receive 4CMenB at months 0, 2, and 6 (referred to as 4CMenB 0-2-6 hereafter); or 4CMenB at months 0 and 6 (referred to as 4CMenB 0-6 hereafter); or MenABCWY (three groups, each receiving one production lot of the MenACWY-CRM component) at months 0 and 6; or MenACWY-CRM at month 0. Demonstration in the per-protocol set of the consistency of three MenACWY-CRM component lots of the MenABCWY vaccine was a primary objective (demonstrated with two-sided 95% CIs for the ratio of human serum bactericidal antibody [hSBA] geometric mean titres against each serogroup within predefined criteria [0·5-2·0]). The primary endpoints (breadth of immune response) for the MenB component of MenABCWY and 4CMenB were measured using the endogenous complement hSBA (enc-hSBA) assay against a panel of 110 diverse MenB invasive disease strains. For each serum sample, 35 strains from the 110 MenB strain panel were randomly selected for testing. The 4CMenB breadth of immune response data have been published separately. For MenABCWY, breadth of immune response was assessed in two analyses: a test-based analysis of the percentage of samples (tests) without bactericidal serum activity against MenB strains 1 month after two MenABCWY doses versus the percentage after one MenACWY-CRM dose in the per-protocol set, and a responder-based analysis of the percentage of participants (responders) whose sera killed 70% or more strains at 1 month after two MenABCWY doses in the full analysis set. A lower limit of two-sided 95% CI above 65% would demonstrate breadth of immune response. Other primary outcomes included non-inferiority (5% margin) of two MenABCWY doses versus two 4CMenB doses by enc-hSBA assay in the per-protocol set, non-inferiority (10% margin) of two MenABCWY doses versus one MenACWY-CRM dose in MenACWY vaccine-naive participants by traditional hSBA assay in the per-protocol set, and safety in all vaccinated participants. This trial is registered with ClinicalTrials.gov, NCT04502693, and is complete.

FINDINGS

Between Aug 14, 2020, and Sept 3, 2021, 3651 participants were enrolled and randomly allocated (900 in the 4CMenB 0-2-6 group and 908 in the 4CMenB 0-6 group, 1666 in the three MenABCWY groups combined, and 177 in the MenACWY-CRM group). All primary objectives for MenABCWY were met. Consistency of immune responses against the three production lots of the MenACWY component of MenABCWY was demonstrated since two-sided 95% CIs for the ratios of hSBA geometric mean titres against serogroups A, C, W, and Y for each pair of lots were within the predefined equivalence criteria. The lot data were pooled for the remainder of MenABCWY endpoints. By enc-hSBA assay, breadth of immune response against the MenB strain panel was 77·9% (95% CI 76·6 to 79·2) in the test-based analysis and 84·1% (81·4 to 86·5; 687 of 817 participants) in the responder-based analysis. Non-inferiority of MenABCWY to 4CMenB was demonstrated by enc-hSBA assay: the difference in percentage of samples with bactericidal serum activity between the MenABCWY group (82·5% [95% CI 82·1 to 83·0]; 21 222 of 25 715) and 4CMenB 0-2 group (83·1% [82·7 to 83·6]; 22 921 of 27 569) was -0·61% (-1·25 to 0·03). Non-inferiority of two-dose MenABCWY to one-dose MenACWY-CRM was demonstrated by traditional hSBA assay, with differences between the MenABCWY group and MenACWY group in percentages of participants with a four-fold rise in hSBA titres of 11·3% (5·9 to 19·0) for serogroup A, 47·2% (38·1 to 56·3) for serogroup C, 35·3% (26·9 to 44·5) for serogroup W, and 27·0% (19·4 to 35·8) for serogroup Y. MenABCWY reactogenicity was mostly of mild or moderate severity and transient, with similar frequencies of adverse events in the MenABCWY and 4CMenB groups and no safety concerns were identified.

INTERPRETATION

This study demonstrates breadth of immune response against a panel of 110 MenB strains for the MenB component of the investigational MenABCWY vaccine, when administered as a 0-6 months schedule to the target population of adolescents and young adults, with predefined criteria for success met for both breadth of immune response endpoints and for non-inferiority versus 4CMenB. This investigational vaccine could provide broad meningococcal serogroup coverage in a simplified immunisation schedule, thus aiding the public health attempt in preventing invasive meningococcal disease due to five Neisseria meningitidis serogroups in adolescents and young adults.

FUNDING

GSK.

Methods to evaluate the performance of a multicomponent meningococcal serogroup B vaccine

Meningococcal serogroup B (MenB) vaccine licensure was based on the assessment of vaccine-induced immune responses by human serum bactericidal antibody (hSBA) assay against a small number of antigen-specific strains complemented by strain coverage predictions. However, the evaluation of vaccine strain coverage is challenging because of genotypic and phenotypic diversity in surface-exposed MenB strain antigens. This narrative review considers the principal methods applied to assess the performance of a multicomponent MenB vaccine at different stages of its development. Traditional hSBA assay against a limited panel of strains is useful at all stages, while predicted strain coverage methods, such as the meningococcal antigen typing system, are used independent of clinical trials. A new method, the endogenous complement hSBA assay, has been developed to evaluate a vaccine's ability to induce a bactericidal immune response in clinical trials, in conditions that approximate real-world settings through the use of each vaccinee's serum as a source of complement and by testing against a panel of 110 epidemiologically representative MenB strains. Each assay, therefore, has a different scope during the vaccine's development and all complement each other, enabling comprehensive evaluation of the performance of multicomponent MenB vaccines, in advance of real-world evidence of vaccine effectiveness and vaccine impact.

Isolation of human monoclonal antibodies from 4CMenB vaccinees reveals PorB and LOS as the main OMV components inducing cross-strain protection

Introduction

The 4CMenB vaccine licensed against serogroup B Neisseria meningitidis (MenB) contains three recombinant proteins and Outer Membrane Vesicles (OMV) from a New Zealand epidemic strain. The protective response mediated on differentmeningococcal strains has been historically ascribed to one of the four main vaccine antigens fHbp, NHBA, NadA, and PorA nominated as the immunodominant antigen of the OMV component. It is however accepted that the extensive cross-protection observed after vaccination may be attributed to other proteins in the OMV. Here we interrogate the B cell responses elicited in humans to the OMV component after 4CMenB vaccination to elucidate the contribution of additional OMV antigens to meningococcal cross-protection.

Methods

Following the isolation of plasmablasts from vaccinees, the OMV-specific human monoclonal antibodies (HumAbs) were recombinantly expressed and characterized for their binding and functional activity on a panel of MenB strains. Their target specificity was assessed through a tailor-made protein array and Western blot.

Results

We found that 18 HumAbs showing bactericidal activity were PorB-specific, 1 was LOS-specific and 4 functional HumAbs remain with unknown targets. We identified three functional classes within the PorB HumAbs, through binding and in silico docking experiments, likely to be elicited from distinct epitopes on PorB and highlighting this antigen as a multi-epitope immunogenic OMV component responsible for distinct cross-protection across multiple MenB strains. Interestingly three of the PorB HumAbs and the LOS-specific HumAb showed bactericidal activity also against gonococcus.

Discussion

We identified PorB and LOS as antigens on the OMV that may be implicated in the real-world observations of moderate protection against gonorrhea infection after OMV-based vaccinations.

Policies for the immunization against serogroup B meningococcus for adolescents immunized during the first two years of life: A mini review

Two vaccines are available to prevent serogroup B meningococcal disease, i.e. the four-component meningococcal serogroup B vaccine (4CMenB) and the bivalent-factor-H-binding-protein meningococcal serogroup B vaccine (MenB-fHbp). Currently, 4CMenB is offered as part of routine infant immunization schedules. Available immunogenicity data showed a progressive decline in protective serum bactericidal antibodies (SBA) titers, with a re-enhancement following a booster dose during infancy. Responses did not seem to be long-lasting and vaccinated individuals might be at risk of meningococcal diseases duriṇg adolescence. Only one study evaluated the possibility to administer a single booster dose to immunocompetent adolescents who received a primary series during infancy. Despite a high proportion of enrollees achieving protective SBA levels 28 days post-booster, titers tended to decrease 1 year after. Immunocompetent adolescents who received a primary series and a booster during the first two years of life might rather benefit from re-vaccination against MenB; current evidence does not support the possibility of a booster.

4CMenB journey to the 10-year anniversary and beyond

The 4-component meningococcal serogroup B (MenB) vaccine, 4CMenB, the first broadly protective, protein-based MenB vaccine to be licensed, is now registered in more than 50 countries worldwide. Real-world evidence (RWE) from the last decade confirms its effectiveness and impact, with infant immunization programs showing vaccine effectiveness of 71-95% against invasive MenB disease and cross-protection against non-B serogroups, including a 69% decrease in serogroup W cases in 4CMenB-eligible cohorts in England. RWE from different countries also demonstrates the potential for additional moderate protection against gonorrhea in adolescents. The real-world safety profile of 4CMenB is consistent with prelicensure reports. Use of the endogenous complement human serum bactericidal antibody (enc-hSBA) assay against 110 MenB strains may enable assessment of the immunological effectiveness of multicomponent MenB vaccines in clinical trial settings. Equitable access to 4CMenB vaccination is required to better protect all age groups, including older adults, and vulnerable groups through comprehensive immunization policies.

Cost of Illness Analysis of Invasive Meningococcal Disease Caused by Neisseria Meningitidis Serogroup B in the Netherlands-a Holistic Approach

INTRODUCTION

Invasive meningococcal disease (IMD) caused by Neisseria meningitidis is a rapidly progressing, rare disease that often presents as meningitis or sepsis. It mostly affects infants and adolescents, with high fatality rates or long-term sequelae. In the Netherlands, serogroup B (MenB) is most prevalent. We aimed to estimate the economic burden of MenB-related IMD between 2015 and 2019, including direct and indirect medical costs from short- and long-term sequelae, from a societal perspective.

METHODS

IMD incidence was based on laboratory-based case numbers from the Netherlands Reference Laboratory for Bacterial Meningitis (Amsterdam UMC, Amsterdam, the Netherlands); there were 74 MenB cases on average per year in the study period 2015-2019. Case-fatality rate (3.8%) and percentage of patients discharged with sequelae (46%) were derived from literature. Direct costs included treatment costs of the acute phase, long-term sequelae, and public health response. Indirect costs were calculated using the human capital (HCA) and friction costs (FCA) approaches, in which productivity losses were estimated for patients and parents during the acute and sequelae phases. Costs were discounted by 4% yearly.

RESULTS

Estimated costs due to MenB IMD in an annual cohort were €3,094,199 with FCA and €9,480,764 with HCA. Direct costs amounted to €2,974,996, of which 75.2% were related to sequelae. Indirect costs related to sequelae were €52,532 with FCA and €5,220,398 with HCA.

CONCLUSION

Our analysis reflects the high economic burden of MenB-related IMD in the Netherlands. Sequelae costs represent a high proportion of the total costs. Societal costs were dependent on the applied approach (FCA or HCA).

The overlooked bacterial pandemic

The COVID-19 pandemic had a significant economic and health impact worldwide. It also reinforced the misperception that only viruses can pose a threat to human existence, overlooking that bacteria (e.g., plague and cholera) have severely haunted and shaped the course of human civilization. While the world is preparing for the next viral pandemic, it is again overlooking a silent one: antimicrobial resistance (AMR). This review proposes to show the impact of bacterial infections on civilization to remind the pandemic potential. The work will also discuss a few examples of how bacteria can mutate risking global spread and devastating outcomes, the effect on the global burden, and the prophylactic and therapeutic measures. Indeed, AMR is dramatically increasing and if the trend is not reversed, it has the potential to quickly turn into the most important health problem worldwide.

The important lessons lurking in the history of meningococcal epidemiology

INTRODUCTION

The epidemiology of invasive meningococcal disease (IMD), a rare but potentially fatal illness, is typically described as unpredictable and subject to sporadic outbreaks.

AREAS COVERED

Meningococcal epidemiology and vaccine use during the last ~ 200 years are examined within the context of meningococcal characterization and classification to guide future IMD prevention efforts.

EXPERT OPINION

Historical and contemporary data highlight the dynamic nature of meningococcal epidemiology, with continued emergence of hyperinvasive clones and affected regions. Recent shifts include global increases in serogroup W disease, meningococcal antimicrobial resistance (AMR), and meningococcal urethritis; additionally, unvaccinated populations have experienced disease resurgences following lifting of COVID-19 restrictions. Despite these changes, a close analysis of meningococcal epidemiology indicates consistent dominance of serogroups A, B, C, W, and Y and elevated IMD rates among infants and young children, adolescents/young adults, and older adults. Demonstrably effective vaccines against all 5 major disease-causing serogroups are available, and their prophylactic use represents a powerful weapon against IMD, including AMR. The World Health Organization's goal of defeating meningitis by the year 2030 demands broad protection against IMD, which in turn indicates an urgent need to expand meningococcal vaccination programs across major disease-causing serogroups and age-related risk groups.

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.

The Influence of Introducing Free Vaccination against Streptococcus pneumoniae on the Uptake of Recommended Vaccination in Poland

Since 2017, pneumococcal vaccination has evolved from a recommended chargeable vaccination to a mandatory, and therefore free, vaccination for all children. While a 10-valent vaccine is commonly used, parents have the option to use a 13-valent vaccine for a fee. This study aimed to investigate whether and how the introduction of free pneumococcal vaccination affected the uptake of recommended vaccination and to assess the association of chargeable pneumococcal vaccination with recommended vaccination. Data from 1595 vaccination record cards kept by six primary care clinics in urban and rural areas of Poland were collected and analyzed for children born between 2015 and 2018. Belonging to the clinic and the year of birth were the only inclusion criteria. Following the introduction of free universal pneumococcal vaccination, more children were vaccinated with the recommended vaccination (61.2% vs. 66.6%, p = 0.026). The most significant change was in vaccination against rotavirus (48.5% vs. 54.4%, p = 0.018) and against meningococcal B bacteria (4.8% vs. 17.0%, p < 0.001). Children who received chargeable pneumococcal vaccination were also significantly more likely to be vaccinated with recommended vaccines (54.6% vs. 75.9%, p < 0.001). In particular, this was the case for multivalent vaccinations-against rotavirus, chickenpox, and meningococcal C bacteria. Reducing the impact of the economic factor, for example, by introducing free vaccinations, should have a positive impact on the uptake of other recommended vaccinations.

MAGLIO study: epideMiological Analysis on invasive meninGococcaL disease in Italy: fOcus on hospitalization from 2015 to 2019

This study analyzed hospital admissions for invasive meningococcal disease (IMD) in epidemiological and economic terms in Italy from 2015 to 2019. The volume of acute admissions for meningococcal diagnosis was analyzed in the period from 2015 to 2019. IMD admissions were identified by ICD-9-CM diagnoses. Costs were assessed using current DRG tariffs. In 2019, a total of 237 admissions for meningococcal disease were recorded in Italy. The mean age of patients was 36.1 years. Lumbar puncture was reported in only 14% of hospital discharge forms. From 2015 to 2019, there was a mean annual reduction of - 1.2% nationally for IMD hospitalizations. For 2019, the total costs for acute inpatient admissions were €2,001,093. Considering annual incidence due to IMD, a significant decrease was noted in the age group from 0 to 1 year (p = 0.010) during 2015-2019. For all years, mortality associated with meningeal syndrome was lower compared to septic shock with or without meningitis. From 2015 to 2019, hospitalizations for IMD appear to be decreasing slightly in Italy, even if mortality remains high. Favorable trends in hospitalizations for IMD were seen in the 0-1-year age group, which may be attributable to increased vaccination. Costs of hospitalizations for IMD remain high.

Meningococcal B Immunisation in Adults and Potential Broader Immunisation Strategies: A Narrative Review

Recombinant vaccines against invasive meningococcal disease due to Neisseria meningitidis serogroup B (MenB) have shown substantial impact in reducing MenB disease in targeted populations. 4CMenB targets four key N. meningitidis protein antigens; human factor H binding protein (fHbp), Neisserial heparin binding antigen (NHBA), Neisseria adhesin A (NadA) and the porin A protein (PorA P1.4), with one or more of these expressed by most pathogenic MenB strains, while MenB-FHbp targets two distinct fHbp variants. While many countries recommend MenB immunisation in adults considered at high risk due to underlying medical conditions or immunosuppression, there are no recommendations for routine use in the general adult population. We reviewed the burden of MenB in adults, where, while incidence rates remain low (and far lower than in young children < 5 years of age at greatest risk), a substantial proportion of MenB cases (20% or more) is now observed in the adult population; evident in Europe, Australia, and in the United States. We also reviewed immunogenicity data in adults from clinical studies conducted during MenB vaccine development and subsequent post-licensure studies. A 2-dose schedule of 4CMenB generates hSBA titres ≥ 1:4 towards all four key vaccine target antigens in up to 98-100% of subjects. For MenB-FHbp, a ≥ fourfold rise in hSBA titres against the four primary representative test strains was observed in 70-95% of recipients following a 3-dose schedule. While this suggests potential benefits for MenB immunisation if used in adult populations, data are limited (especially for adults > 50 years) and key aspects relating to duration of protection remain unclear. Although a broader adult MenB immunisation policy could provide greater protection of the adult population, additional data are required to support policy decision-making.

Four-Component Recombinant Protein-Based Vaccine Effectiveness Against Serogroup B Meningococcal Disease in Italy

Importance

Population-based data on the 4-component recombinant protein-based (4CMenB) vaccine effectiveness and reduction in incidence rate ratios (IRRs) are continuously needed to assess vaccine performance in the prevention of serogroup B invasive meningococcal disease (IMD).

Objective

To assess the effectiveness and reduction in IRRs associated with the 4CMenB vaccine in the pediatric population in 6 regions in Italy.

Design, Setting, and Participants

This retrospective cohort screening study and case-control study included data from children aged younger than 6 years in 6 highly populated Italian regions from January 1, 2006, to January 1, 2020. Participants included children younger than 6 years diagnosed with serogroup B IMD without predisposing factors. Data were collected from regional surveillance and vaccination registries and were analyzed from September 2021 to January 2022.

Exposures

Routine 4CMenB vaccination, per regional vaccination programs.

Main Outcomes and Measures

The main outcome was the effectiveness of the 4CMenB vaccine in the prevention of serogroup B IMD in the population of children aged younger than 6 years in 6 Italian regions. The percentages of vaccine effectiveness (VE) were obtained through the concomitant use of a screening method and a case-control study. Secondary outcomes were the comparison of effectiveness results obtained using the 2 different computational methods, the description of serogroup B IMD incidence rates, and reduction in IRRs before and after 4CMenB introduction, as a proxy for vaccine impact.

Results

The cohort screening study included a resident population of 587 561 children younger than 6 years in 3 regions with similar surveillance protocols, and the matched-case controls study assessed a resident population of 1 080 620 children younger than 6 years in 6 regions. Analyses found that 4CMenB VE in fully immunized children was 94.9% (95% CI, 83.1%-98.4%) using the screening method and 91.7% (95% CI, 24.4%-98.6%) using the case-control method. Overall reduction in IRR was 50%, reaching 70% in regions with early-start vaccination schedules. The case-control method involving 6 highly-populated Italian regions included 26 cases and 52 controls and found an estimated VE of 92.4% (95% CI, 67.6%-97.9%) in children old enough for the first vaccine dose and 95.6% (95% CI, 71.7%-99.1%) in fully immunized children. VE was more than 90% for partially immunized children. Even in regions where the first dose was administered at age 2 months, almost 20% of unvaccinated cases were among infants too young to receive the first 4CMenB dose.

Conclusions and Relevance

This screening cohort study and matched case-controls study found high effectiveness of 4CMenB vaccination and greater reduction in IRR for early-start vaccination schedules in preventing invasive serogroup B meningococcal disease. The high proportion of children too young to be vaccinated among unvaccinated cases suggests that starting the vaccination even earlier may prevent more cases. Screening and case-control methods provided similar estimates of VE: either method may be used in different study settings, but concomitant use can provide more robust estimates.

Challenges in synthesis of real-world vaccine effects on meningococcal serogroup B disease for 4CMenB vaccine post-licensure effectiveness studies: A systematic review

BACKGROUND

Real-world studies on vaccine effects are diverse in terms of objectives, study setting and design, data type and scope, and analysis methods. In this review, we describe and discuss four-component meningococcal serogroup B vaccine (4CMenB vaccine, Bexsero) real-world studies with the aim of synthesizing their findings with application of standard methods.

METHODS

We performed a systematic literature review of all real-world studies on 4CMenB vaccine effects on meningococcal serogroup B disease, with no restriction for population age, vaccination schedule and/or type of vaccine effect evaluated (vaccine effectiveness [VE] and vaccine impact [VI] outcomes) published since its licensure in 2013 (from January 2014 until July 2021) in PubMed, Cochrane and the grey literature. We then aimed to synthesize the findings of the identified studies through application of standard synthesis methods.

RESULTS

According to reported criteria we retrieved five studies presenting estimates on 4CMenB vaccine effectiveness and impact. These studies showed great diversity in population, vaccination schedule and analysis methods mainly due to diversity in vaccine strategies and recommendations in the study settings. Directed by this diversity, no quantitative pooling methods to synthesize findings could be applied; instead we descriptively assessed study methods. We report VE estimates ranging from 59% to 94% and VI estimates ranging from 31% to 75%, representing diverse age groups, vaccination schedules and analysis methods.

CONCLUSION

Both vaccine outcomes showed real-life effectiveness of 4CMenB vaccine despite differences in study methodologies and vaccination strategies. Based on appraisal of study methods, we highlighted the need for an adapted tool which facilitates synthesis of heterogenic real-world vaccine studies when quantitative pooling methods are not applicable.

Invasive Meningococcal Disease epidemiology and vaccination strategies in four Southern European countries: a review of the available data

INTRODUCTION

Invasive meningococcal disease (IMD) is a major health concern which can be prevented through vaccination. Conjugate vaccines against serogroups A, C, W and Y and two protein-based vaccines against serogroup B are currently available in the European Union.

AREAS COVERED

We present epidemiologic data for Italy, Portugal, Greece and Spain using publicly available reports from national reference laboratories and national or regional immunization programs (1999-2019), aiming to confirm risk groups, and describe time trends in overall incidence and serogroup distribution, as well as impact of immunization. Analysis of circulating MenB isolates in terms of the surface factor H binding protein (fHbp) using PubMLST is discussed as fHbp represents an important MenB vaccine antigen. Predictions of potential reactivity of the two available MenB vaccines (MenB-fHbp and 4CMenB) with circulating MenB isolates are also provided as assessed using the recently developed MenDeVAR tool.

EXPERT OPINION

Understanding dynamics of IMD and continued genomic surveillance are essential for evaluating vaccine effectiveness, but also prompting proactive immunization programs to prevent future outbreaks. Importantly, the successful design of further effective meningococcal vaccines to fight IMD relies on considering the unpredictable epidemiology of the disease and combining lessons learnt from capsule polysaccharide vaccines and protein-based vaccines.

4CMenB sustained vaccine effectiveness against invasive meningococcal B disease and gonorrhoea at three years post program implementation

OBJECTIVES

To evaluate persistence of vaccine effectiveness (VE) and vaccine impact (VI) on invasive meningococcal B (MenB) disease and gonorrhoea at three years after implementation of a state funded 4CMenB program for infants, children, adolescents and young people in South Australia.

METHODS

VI was assessed using a Poisson or negative binomial regression model, and VE was estimated using screening and case-control methods. Chlamydia controls were used to estimate VE in the primary analysis to control potential confounding effects such as high-risk sexual behaviour associated with sexually transmitted infections.

RESULTS

During the three-year program, reductions of 63.1% (95%CI 29.0% to 80.9%) and 78.5% (95%CI 33.0% to 93.1%) in incidence of MenB disease were observed in infants and adolescents, respectively. There were no cases in infants who had received three doses of 4CMenB. Two-dose VE against MenB disease was 90.7% (95%CI 6.9% to 99.1%) for the childhood program and 83.5% (95%CI 0 to 98.2%) for the adolescent program. Two-dose VE against gonorrhoea in adolescents was 33.2% (95%CI 15.9% to 47.0%). Lower VE estimates were demonstrated after 36 months post-vaccination (23.2% (95%CI 0 to 47.5%) >36 months post-vaccination compared to 34.9% (95%CI 15.0% to 50.1%) within 6-36 months). Higher VE estimates were found after excluding patients with repeat gonorrhoea infections (37.3%, 95%CI 19.8% to 51.0%). For gonorrhoea cases co-infected with chlamydia VE was maintained (44.7% (95%CI 17.1% to 63.1%).

CONCLUSION

The third-year evaluation results show persistent vaccine effectiveness of 4CMenB against MenB disease in infants and adolescents. As this is the first ongoing program for adolescents, moderate vaccine protection against gonorrhoea with waning effectiveness three years post-vaccination was demonstrated in adolescents and young adults. The additional protection of 4CMenB vaccine against gonorrhoea, likely through cross-protection should be considered in cost-effectiveness analyses. A booster dose may need to be further evaluated and considered in adolescents due to waning protection against gonorrhoea demonstrated after 36 months post-vaccination.

Meningococcal disease within the Gulf Cooperation Council Countries

This review reports on the recent epidemiology of invasive meningococcal disease (IMD) within the Gulf Cooperation Council (GCC) Countries (focusing from 2012 onwards), the existing immunization strategies and the potential for IMD resurgence. MenACWY vaccination is now established in infant or adolescent immunization programs in Saudi Arabia, Bahrain, Kuwait, and the United Arab Emirates. At present, GCC Countries do not include MenB immunization. National health surveillance reports indicate a total of 156 IMD cases reported across the GCC Countries between 2012 and 2021; between 30% and 80% of cases were reported in individuals aged ≥15 years. Lack of serogroup data hinders the assessment of vaccine impact and decision-making on additional vaccine introductions (e.g. MenB immunization). Hajj/Umrah pilgrimage and the increasing number of large-scale commercial and social events held in the GCC Countries pose a potential risk for future IMD outbreaks. Immunization policies for such events could be strengthened.

Insights from targeting transferrin receptors to develop vaccines for pathogens of humans and food production animals

While developing vaccines targeting surface transferrin receptor proteins in Gram-negative pathogens of humans and food production animals, the common features derived from their evolutionary origins has provided us with insights on how improvements could be implemented in the various stages of research and vaccine development. These pathogens are adapted to live exclusively on the mucosal surfaces of the upper respiratory or genitourinary tract of their host and rely on their receptors to acquire iron from transferrin for survival, indicating that there likely are common mechanisms for delivering transferrin to the mucosal surfaces that should be explored. The modern-day receptors are derived from those present in bacteria that lived over 320 million years ago. The pathogens represent the most host adapted members of their bacterial lineages and may possess factors that enable them to have strong association with the mucosal epithelial cells, thus likely reside in a different niche than the commensal members of the bacterial lineage. The bacterial pathogens normally lead a commensal lifestyle which presents challenges for development of relevant infection models as most infection models either exclude the early stages of colonization or subsequent disease development, and the immune mechanisms at the mucosal surface that would prevent disease are not evident. Development of infection models emulating natural horizontal disease transmission are also lacking. Our aim is to share our insights from the study of pathogens of humans and food production animals with individuals involved in vaccine development, maintaining health or regulation of products in the human and animal health sectors.

Safety profile of MenB-FHBp vaccine among adolescents: data from surveillance of Adverse Events Following Immunization in Puglia (Italy), 2018-2020

MenB-FHBp was licensed in Europe in 2017 from the age of 10. In the “postmarketing life” of a new vaccine, surveillance of Adverse Events Following Immunization (AEFI) is crucial, to better understand the pattern of safety and the effectiveness. This paper describes the MenB-FHBp AEFIs notified in Puglia in 2018–2021, to take a picture of the safety profile of this vaccine in the real life, four years after its introduction in Italy. This is a retrospective observational study. Data were collected from the list of AEFIs notified after MenB-FHBp vaccine administration in Puglia in 2018–2020, and the number of doses of this vaccine administered in the same period. AEFIs were classified according to WHOʻs algorithm, and causality assessment was carried out for serious AEFIs. From January 2018 to December 2020, in Puglia, 43,061 doses of MenB-FHBp were administered and 42 MenB-FHBp AEFIs (reporting rate: 97.5 per 100,000 doses administered) were reported. Among these, 12 were classified as severe (28.6%; reporting rate 27.9 per 100,000 doses). Overall, the male/female ratio in AEFIs was 1:1. The median age of people who suffered from AEFIs was 12 years (range 11–13). For the 11 serious AEFIs for which the classification was “consistent causal association,” the diagnosis was hyperpyrexia (reporting rate 13.9 per 100,000 doses), fainting (rate 4.6 per 100,000 doses), urticaria (rate 2,3 per 100,000 doses), convulsions (rate 2,3 per 100,000 doses), and vomit (rate 2,3 per 100,000 doses). No deaths or impairment were notified in studied AEFIs. The picture of MenB-FHBp vaccine supports that the risk of AEFIs is in line with previous published data and in general acceptable.

Public health perspective of a pentavalent meningococcal vaccine combining antigens of MenACWY-CRM and 4CMenB

OBJECTIVES

Invasive meningococcal disease (IMD) is a life-threatening disease that can rapidly progress to death or leave survivors with severe, life-long sequelae. Five meningococcal serogroups (A, B, C, W and Y) account for nearly all IMD. Meningococcal serogroup distribution fluctuates over time across the world and age groups. Here, we consider the potential public health impact of a pentavalent MenABCWY vaccine developed to help further control meningococcal disease and improve immunisation rates.

RESULTS

The GSK MenABCWY vaccine combines the antigenic components of MenACWY-CRM (Menveo®) and 4CMenB (Bexsero®), building on a wide body of clinical experience and real-world evidence. Both approved vaccines have acceptable safety profiles, demonstrate immunogenicity, and are broadly used, including in national immunisation programmes in several countries. Since the advent of quadrivalent vaccines, public health in relation to IMD has improved, with a decline in the overall incidence of IMD and an increase in vaccine coverage.

CONCLUSION

A pentavalent MenABCWY has the potential to provide further public health benefits through practical, broad IMD protection programmes encompassing serogroups A, B, C, W and Y, and is currently in late-stage development.

Meningococcal Disease and Immunization Activities in Hajj and Umrah Pilgrimage: a review

Invasive meningococcal disease (IMD) outbreaks associated with Hajj and Umrah pilgrimage events in the Kingdom of Saudi Arabia (KSA) are well recognized. Past outbreaks have been associated with substantial intercontinental spread of specific Neisseria meningitidis serogroups. The emergence of meningococcal serogroup W (MenW) was a global concern following the 2000/2001 Hajj outbreaks. Broader compulsory meningococcal serogroups A, C, W and Y (MenACWY) immunization strategies for pilgrims were introduced in response to these events and led to substantial declines in IMD cases associated with these mass gatherings. However, there remains potential for future outbreaks either within KSA during the Hajj or in local populations via pilgrim meningococcal transmission on their return. While the annual Hajj involves pilgrims from over 185 countries, two-thirds of these arrive from 13 countries, chiefly from across South-East Asia, the Middle East and North African (MENA) regions; for which we review the relevant epidemiology of IMD and meningococcal carriage. While disease surveillance is limited and data are often lacking, MenB is an important serogroup associated with IMD and carriage in a number of countries. Available literature suggests that most pilgrims receive polysaccharide MenACWY vaccines (which do not impact carriage and onward transmission) and incomplete compliance with visa/entry immunization regulations is reported. Existing preventative approaches for visiting pilgrims require continued oversight. More complete compliance and switching to the conjugated MenACWY vaccine can provide more robust and broader protection for pilgrims. Additional immunization options could also be considered.

A comparison of national vaccination policies to prevent serogroup B meningococcal disease

Objectives:

To understand the global landscape of prevention and control efforts targeting serogroup B meningococcal (MenB) disease and to identify the key challenges and gaps yet to be addressed.

Methods:

We conducted a comprehensive review of policies and practices for the use of protein-based MenB vaccines (Bexsero^® [GlaxoSmithKline] and Trumenba^® [Pfizer]) in all countries (n = 58) where either or both vaccine is authorized for use. We searched the literature (PubMed) and websites of health ministries and other relevant agencies to identify policy documents and plans and collect information about implementation timelines, target groups, vaccines being used, recommended schedules, and coverage data. Experts in the field were contacted for additional details andclarifications, as needed.

Results:

We found evidence of a national MenB vaccination policy in 24 out of 58 countries where one or both protein-based MenB vaccines are authorized. Of these, 15 countries have included MenB vaccination in their immunization plans for at least one age-based risk group (mostly infants), 21 have issued recommendations for various risk groups based on underlying medical conditions (e.g. asplenia), and 13 have done so for select groups at increased risk of exposure (e.g. laboratory staff). Recommended vaccination schedules and number of doses, where available, varied widely. Vaccination coverage data for age-based risk groups were not obtained for most countries.

Conclusions:

Our findings highlighted the significant heterogeneity in recommendations for MenB vaccination across countries. Greater transparency in reporting MenB vaccination recommendations and more robust data on implementation and the impact of vaccination would better facilitate optimizing MenB prevention strategies.

Real-world implementation of 4-component meningococcal serogroup B vaccine (4CMenB): implications for clinical practices

INTRODUCTION

Invasive meningococcal disease due to serogroup B (MenB) is an uncommon but life-threatening disease. The 4-component meningococcal serogroup B vaccine (4CMenB) is the only MenB vaccine with real-world evidence supporting a reduction in incidence without safety concerns.

AREAS COVERED

We reviewed recommendations and real-world implementation of 4CMenB in National Immunization Programs (NIPs) and implications for clinical practice through a non-systematic literature search.

EXPERT OPINION

4CMenB is registered in 45 countries, 33 of which recommend it clinically: nine for infants, children, adolescents, and high-risk groups; 11 for infants and high-risk groups; the US for individuals aged 16-23 years and high-risk groups; two for infants; 10 for high-risk groups and/or outbreak control. Dosing schedule varies between countries. To date, nine countries include 4CMenB in their NIP: UK, Andorra, Ireland, Italy, San Marino, Lithuania, Malta, Czech Republic, and Portugal. Australia funds it for Aboriginal and Torres Strait Islander children under 2 years, and high-risk individuals. South Australia funds for all infants and adolescents. Many factors influenced introduction into NIPs: disease burden, public awareness, cost-effectiveness, prior meningococcal vaccination programs, efficacy and safety profile. In the future, more countries might consider including 4CMenB in their NIP due to growing evidence on effectiveness and safety.

Public Health Impact and Cost-Effectiveness Analysis of Routine Infant 4CMenB Vaccination in Germany to Prevent Serogroup B Invasive Meningococcal Disease

Introduction

Invasive meningococcal disease (IMD) is an uncommon, severe, life-threatening disease primarily affecting infants, with potential lifelong sequelae. Neisseria meningitidis (Nm) serogroup B (MenB) causes most IMD cases in Germany, many of which can be prevented with four-component MenB (4CMenB) vaccination. The potential public health and economic impact of introducing routine 4CMenB infant vaccination in Germany was assessed.

Methods

A dynamic transmission-based cost-effectiveness model adapted for Germany assessed the impact of infant 4CMenB universal mass vaccination (UMV) versus no vaccination. The model included the latest real-world evidence on vaccine effectiveness, the comprehensive burden of disease on patients (sequelae) and their family (quality of life impact), comprehensive German IMD costs, and vaccination uptake assumptions.

Results

The largest public health impact was predicted in children: a rapid decline, 5 years after UMV implementation, of 39.9% (34.7%) for MenB (all IMD) cases aged 0–4 years and 42.4% (36.8%) in infants. Over lifetime (100-year time horizon), 4CMenB could prevent 3154 MenB (3303 all IMD) cases, 291 MenB (304 all IMD) deaths and 1370 MenB (1435 all IMD) long-term sequelae. 4CMenB saved 25,878 quality-adjusted life-years (QALYs), at a cost of €188,762 per QALY gained in the base case (societal perspective including lost productivity). Scenarios including potential Nm carriage protection (enabling herd protection) or societal preferences for the prevention of severe diseases led to more cost-effective results, while a scenario excluding IMD impact beyond the patient with increased discounting of vaccination health benefits produced less cost-effective results.

Conclusions

MenB IMD is a vaccine-preventable disease. This analysis for Germany can inform decision-makers on the potential impact of introducing infant 4CMenB UMV. The program is predicted to rapidly produce health benefits (reduction in child cases, deaths and sequelae) at a cost per QALY to society of around €190,000 (base case), decreasing to around €78,000 when considering societal preferences and IMD underreporting.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00573-w.

Invasive meningococcal disease (IMD) is an uncommon but severe infection, usually presenting as meningitis and/or sepsis, caused by the bacteria Neisseria meningitidis. Most cases occur in infants, young children and adolescents. Patients who survive the disease can develop lifelong sequelae, such as physical, neurological and psychological/behavioural problems that impact their quality of life and that of their family/caregivers. This disease can be prevented by vaccination. The use of the four-component meningococcal serogroup B vaccine (4CMenB) in countries like Germany can prevent the most common form of this disease, IMD caused by serogroup B. This study assessed the public health and economic impact of infant vaccination in Germany with 4CMenB. For this, the authors used an economic model that measured the lifetime impact of the disease on patients but also on their families. The model predicted that after 5 years of vaccination, the number of cases and deaths in infants and young children aged 0–4 years would rapidly decrease by almost 40%. Over a long-term horizon of 100 years, this number was predicted to remain stable. Due to the reduced number of cases, vaccination would also result in fewer deaths and patients with sequelae, as well as cost savings for the healthcare system and society due to the reduced loss of productivity. In conclusion, in Germany, IMD caused by serogroup B is preventable through vaccination, and the 4CMenB vaccine in German infants is predicted to rapidly reduce the disease burden, save lives and prevent healthcare costs.

Looking beyond meningococcal B with the 4CMenB vaccine: the Neisseria effect

Infections with Neisseria meningitidis and Neisseria gonorrhoeae have different clinical manifestations, but the bacteria share up to 80-90% genome sequence identity. The recombinant meningococcal serogroup B (MenB) vaccine 4CMenB consists of four antigenic components that can be present in non-B meningococcal and gonococcal strains. This comprehensive review summarizes scientific evidence on the genotypic and phenotypic similarities between vaccine antigens and their homologs expressed by non-B meningococcal and gonococcal strains. It also includes immune responses of 4CMenB-vaccinated individuals and effectiveness and impact of 4CMenB against these strains. Varying degrees of strain coverage were estimated depending on the non-B meningococcal serogroup and antigenic repertoire. 4CMenB elicits immune responses against non-B meningococcal serogroups and N. gonorrhoeae. Real-world evidence showed risk reductions of 69% for meningococcal serogroup W clonal complex 11 disease and 40% for gonorrhea after 4CMenB immunization. In conclusion, functional antibody activity and real-world evidence indicate that 4CMenB has the potential to provide some protection beyond MenB disease.

Willingness of children and adolescents to have a COVID-19 vaccination: Results of a large whole schools survey in England

BACKGROUND

Vaccine hesitancy has affected COVID-19 adult vaccination programs in many countries. Data on hesitancy amongst child and adolescent populations is largely confined to parent opinion. We investigated the characteristics of vaccine hesitant children and adolescents using results from a large, school-based self-report survey of the willingness to have a COVID-19 vaccination in students aged 9 -18 years in England.

METHODS

Data from the OxWell Student Survey on mental health, life experiences and behaviours were used, collected from four counties across England. Local authority partners recruited schools. The vaccine hesitancy question gave six response options and were clustered to inform delivery: eager and willing were categorised as vaccination 'opt-in', don't know and not bothered categorised as 'undecided', and unwilling and anti-vaccination categorised as 'opt-out'. We conducted a multinomial regression to determine associations between vaccine hesitancy and sociodemographic, health behaviour and social connection variables.

FINDINGS

27,910 students from 180 schools answered the vaccine hesitancy question between 14th May and 21st July 2021, of whom 13984 (50.1%) would opt-in to take a vaccination, 10322 (37.0%) were undecided, and 3604 (12.9%) would opt-out. A lower percentage of younger students reported that they would opt-in to vaccination, for example, 35.7% of 9-year-olds and 51.3% of 13-year-olds compared to 77.8% of 17-year-olds would opt-in to take a vaccination. Students who were 'opt-out' or 'undecided' (a combined 'vaccine hesitant' group) were more likely to come from deprived socioeconomic contexts with higher rates of home rental versus home ownership and their school locations were more likely to be in areas of greater deprivation. They were more likely to smoke or vape, spend longer on social media, feel that they did not belong in their school community but had lower levels of anxiety and depression. The vaccine hesitant students- the undecided and opt-out groups- were similar in profile, although the opt-out students had higher reported confirmed or probable previous COVID-19 infection than the opt-in group, whereas those undecided, did not.

INTERPRETATION

If government vaccination strategies move towards vaccinating younger school-aged students, efforts to increase vaccination uptake may be necessary. Compared with students who would opt-in, those who were vaccine hesitant had greater indicators of social deprivation and felt a lack of community cohesion by not feeling a sense of belonging at their school. There were indications that those students who would opt-out had higher levels of marginalisation and mistrust. If programmes are rolled out, focus on hesitant younger students will be important, targeting more marginalised and deprived young people with information from trusted sources utilising social media; improving access to vaccination centres with provision both in and outside school; and addressing fears and worries about the effects of the vaccine. The main limitation of this study is that the participant group may not be wholly representative of England or the UK, which may bias population-level estimates of willingness to be vaccinated.

FUNDING

The Westminster Foundation, the National Institute for Health Research (NIHR) Applied Research Collaboration Oxford and Thames Valley at Oxford Health NHS Foundation Trust and the NIHR Oxford Health Biomedical Research Centre.