Neisseria meningitidis: epidemiology, treatment and prevention in adolescents

The Impact of Social Determinants of Health on Meningococcal Vaccination Awareness, Delivery, and Coverage in Adolescents and Young Adults in the United States: A Systematic Review

Vaccines remain a fundamental intervention for preventing illness and death. In the United States, suboptimal vaccine uptake in adolescents and young adults has been observed for meningococcal conjugate (MenACWY) and serogroup B meningococcal (MenB) vaccines, particularly among marginalized communities, despite current recommendations by the Advisory Committee on Immunization Practices. A systematic literature search was conducted in the MEDLINE and MEDLINE In-Process, Embase, Cochrane, PsychInfo, and CINAHL databases to identify both drivers of, and barriers to, MenACWY and MenB vaccine uptake in adolescents and young adults. A total of 34 of 46 eligible studies that presented outcomes stratified by race/ethnicity, geography, and socioeconomic status were selected for review. Results showed MenACWY and MenB vaccination coverage in adolescents and young adults is impacted by racial/ethnic, socioeconomic, and geographic disparities. Gaps also exist in insurance for, or access to, these vaccines in adolescents and young adults. Moreover, there was variability in the understanding and implementation of the shared decision-making recommendations for the MenB vaccine. Disease awareness campaigns, increased clarity in accessing all meningococcal vaccines, and further research on the relationships between measures of marginalization and its impact on vaccine coverage in adolescents and young adults are needed to reduce the incidence of severe infections.

Beyond the approved: target sites and inhibitors of bacterial RNA polymerase from bacteria and fungi

Covering: 2016 to 2022RNA polymerase (RNAP) is the central enzyme in bacterial gene expression representing an attractive and validated target for antibiotics. Two well-known and clinically approved classes of natural product RNAP inhibitors are the rifamycins and the fidaxomycins. Rifampicin (Rif), a semi-synthetic derivative of rifamycin, plays a crucial role as a first line antibiotic in the treatment of tuberculosis and a broad range of bacterial infections. However, more and more pathogens such as Mycobacterium tuberculosis develop resistance, not only against Rif and other RNAP inhibitors. To overcome this problem, novel RNAP inhibitors exhibiting different target sites are urgently needed. This review includes recent developments published between 2016 and today. Particular focus is placed on novel findings concerning already known bacterial RNAP inhibitors, the characterization and development of new compounds isolated from bacteria and fungi, and providing brief insights into promising new synthetic compounds.

A Decade of Fighting Invasive Meningococcal Disease: A Narrative Review of Clinical and Real-World Experience with the MenACWY-CRM Conjugate Vaccine

The quadrivalent A, C, W and Y meningococcal vaccine conjugated to nontoxic mutant of diphtheria toxin (MenACWY-CRM) has been licensed since 2010 for the prevention of invasive meningococcal disease (IMD), an uncommon but life-threatening condition. Here, we summarize the experience accrued with MenACWY-CRM during the first decade since its licensure, by providing an overview of clinical trials investigating the safety, immunogenicity and co-administration of MenACWY-CRM with other vaccines as well as presenting real-world evidence regarding the impact of MenACWY-CRM vaccination on carriage and IMD incidence. MenACWY-CRM has demonstrated an acceptable clinical safety profile across a wide range of age groups; no safety concerns have been reported in special populations, such as immunocompromised infants and toddlers, or pregnant women. MenACWY-CRM has also been proven to be immunogenic in various age groups and geographic settings, and a booster dose has been shown to elicit strong anamnestic responses in all studied populations, irrespective of the vaccine used for priming. With no clinically relevant vaccine interactions reported, MenACWY-CRM is being conveniently integrated into existing vaccination programs for various age and risk groups; this possibility of co-administration helps improving vaccine coverage and streamlining the healthcare process of fighting preventable infectious diseases. Vaccination of adolescents and adults has been proven to reduce nasopharyngeal carriage for serogroups C, W and Y, which is an important element in reducing transmission. Real-world evidence indicates that MenACWY-CRM can reduce IMD incidence even in high-exposure groups. When combined with vaccines against serogroup B meningococci, MenACWY-CRM can offer protection against five of the most common serogroups responsible for IMD, which is an important advantage in the continuously evolving landscape of meningococcal serogroup epidemiology.

Invasive meningococcal disease is an uncommon but life-threatening infection that appears as meningitis and/or sepsis. It is caused by Neisseria meningitidis, a bacteria commonly present in the throat or nose. Vaccination with MenACWY-CRM (Menveo, GSK) helps to prevent invasive meningococcal disease caused by four of the most common N. meningitidis serogroups (A, C, W and Y). This vaccine has been licensed for 10 years: we summarized here all available evidence gathered since the vaccine has been available in general practice, from clinical development to real-world experience. Information gained during clinical trials of MenACWY-CRM confirms that vaccination is well tolerated, has an acceptable safety profile and would induce significant protection when given to individuals of various ages such as infants, toddlers, children, adolescents and adults, and when administered at the same time as routine or traveler vaccinations as well as vaccines against serogroup B meningococci (4CMenB). Vaccination with MenACWY-CRM has been shown to decrease the number of serogroup C, W and Y meningococci found in the nose and throat in adolescents and adults as well as the occurrence of invasive meningococcal disease in a high-exposure population from a real-world setting. MenACWY-CRM can conveniently be integrated into most of the existing vaccination schedules for various age and risk groups. When combined with vaccination against serogroup B meningococci, MenACWY-CRM can contribute to providing protection against five of the most common serogroups responsible for invasive meningococcal disease.

Point-of-critical-care diagnostics for sepsis enabled by multiplexed micro and nanosensing technologies

Sepsis is responsible for the highest economic and mortality burden in critical care settings around the world, prompting the World Health Organization in 2018 to designate it as a global health priority. Despite its high universal prevalence and mortality rate, a disproportionately low amount of sponsored research funding is directed toward diagnosis and treatment of sepsis, when early treatment has been shown to significantly improve survival. Additionally, current technologies and methods are inadequate to provide an accurate and timely diagnosis of septic patients in multiple clinical environments. For improved patient outcomes, a comprehensive immunological evaluation is critical which is comprised of both traditional testing and quantifying recently proposed biomarkers for sepsis. There is an urgent need to develop novel point-of-care, low-cost systems which can accurately stratify patients. These point-of-critical-care sensors should adopt a multiplexed approach utilizing multimodal sensing for heterogenous biomarker detection. For effective multiplexing, the sensors must satisfy criteria including rapid sample to result delivery, low sample volumes for clinical sample sparring, and reduced costs per test. A compendium of currently developed multiplexed micro and nano (M/N)-based diagnostic technologies for potential applications toward sepsis are presented. We have also explored the various biomarkers targeted for sepsis including immune cell morphology changes, circulating proteins, small molecules, and presence of infectious pathogens. An overview of different M/N detection mechanisms are also provided, along with recent advances in related nanotechnologies which have shown improved patient outcomes and perspectives on what future successful technologies may encompass. This article is categorized under: Diagnostic Tools > Biosensing.

Use of Cost-Effectiveness Analyses for Decisions About Vaccination Programs for Meningococcal Disease in the United States, United Kingdom, The Netherlands, and Canada

INTRODUCTION

Meningococcal vaccines to protect against invasive meningococcal disease (IMD) vary in terms of vaccine technology and serogroup coverage (Polysaccharide MnACWY, conjugated C and ACWY, outer membrane vesicle-based or protein-based B vaccines), and the national recommendations for each of them vary in terms of target population and number of doses. We sought to understand factors associated with the evolution of meningococcal vaccination program recommendations in four countries with formal evaluation processes: the UK, US, the Netherlands, and Canada.

AREAS COVERED

A targeted review of published literature and internet sources for the four countries relating to meningococcal vaccination decision-making was conducted. The review focused on the impact of cost-effectiveness analyses on vaccine policy decisions and the extent to which variation in incidence of IMD and its potential catastrophic consequences influenced policy decisions.The evolution of meningococcal vaccine recommendations in the four countries was mainly driven by changes in vaccine availability and changes in serogroup incidence. Public pressure due to the catastrophic nature of IMD influenced recommendations. The role of cost-effectiveness analyses varied across the 4 countries.

EXPERT OPINION

The value of implementing meningococcal vaccination programs should be assessed using factors beyond those included in traditional cost-effectiveness analyses.

Evaluating Vaccination Programs That Prevent Diseases With Potentially Catastrophic Health Outcomes: How Can We Capture the Value of Risk Reduction?

In the last 5 years, guidelines have been developed for performing cost-effectiveness analyses (CEAs) for the economic evaluation of vaccination programs against infectious diseases. However, these cost-effectiveness guidelines do not provide specific guidance for including the value of reducing the risk of rare but potentially catastrophic health outcomes, such as mortality or long-term sequelae. Alternative economic evaluation methods, including extended CEA, the impact inventory, cost-benefit analyses, willingness to pay or the value of a statistical life, to capture the value of this risk reduction could provide more complete estimates of the value of vaccination programs for diseases with potentially catastrophic health and nonhealth outcomes. In this commentary, using invasive meningococcal disease as an example, we describe these alternative approaches along with examples to illustrate how the benefits of vaccination in reducing risk of catastrophic health outcomes can be valued. These benefits are not usually captured in CEAs that only include population benefits estimated as the quality-adjusted life-years gained and reduced costs from avoided cases.

Cost-effectiveness of meningococcal polysaccharide serogroups A, C, W-135 and Y conjugate vaccine in Australian adolescents

OBJECTIVES

The incidence of invasive meningitis disease (IMD) is increasing in Australia. A conjugate vaccine of meningococcal polysaccharide serogroups A, C, W and Y (MenACWY) is currently indicated for infants aged 12 months on the Australian National Immunisation Program. This study sought to determine the cost-effectiveness of a broader MenACWY vaccination program for Australians aged 15 to 19 years.

METHODS

A Markov model was constructed to simulate the incidence and consequences of IMD in Australians aged 0-84 years, with follow up until age 85 years. The model comprised four health states: 'Alive with no previous IMD', 'Alive, post IMD without long-term complications', 'Alive, post IMD with long-term complications' and 'Dead'. Decision analysis compared the clinical consequences and costs of a vaccination program versus no vaccination from the perspective of the Australian health care system. Age-specific incidence of IMD and fatality rates were derived from Australian surveillance data. Vaccine coverage, vaccine efficacy and herd immunity were based on published data. The total cost for MenACWY vaccination was AU$56 per dose. Costs and health outcomes were discounted by 5% per annum (in the base-case analysis).

RESULTS

Compared to no vaccination, a MenACWY vaccination program targeted at Australians aged 15-19 years was expected to prevent 1664 IMD cases in the Australian population aged 0-84 years followed up until age 85 years. The program would lead to 1131 life years (LYs) and 2058 quality adjusted life years (QALYs) gained at a total cost of AU$115 million (all discounted values). These equated to incremental cost-effectiveness ratios of AU$101,649 per LY gained and AU$55,857 per QALY gained. A probabilistic sensitivity analysis demonstrated a likelihood of cost-effectiveness of 34.6%, assuming a willingness to pay threshold of AU$50,000 per QALY gained.

CONCLUSION

The likelihood of this program being cost-effective under a willingness to pay threshold AU$50,000 per QALY gained is 35%.

Do HCWs adequately know about meningitis and 4CMenB vaccine and recommend its use to parents? A cross sectional analysis in Campania Region, Italy

Invasive meningococcal disease (IMD) is a severe disease caused by various Neisseria meningitidis serogroups that represents a serious public health problem worldwide. In Italy, serogroups B and C are the major causes of IMD. On 14 January 2013, the European Medicines Agency authorized the use of the first vaccine available to protect against meningococcal serogroup B (4CMenB). The aim of this study was to assess the IMD epidemiology knowledge and 4CMenB vaccine attitudes of healthcare workers (HCWs) with regard to recommending this vaccine for use, vaccine practices and infectious disease control in the Campania region in Italy. A cross-sectional study was conducted among 293 HCWs (49.5% physicians and 46.4% nurses)interviewed using a self-administered questionnaire. The majority of the HCWs had sufficient knowledge about the disease incidence and lethality, but they were less informed about the higher risk age categories and the serogroups most frequently involved. Additionally, their knowledge about the vaccine was poor with regard to the targeted categories and side effects. Approximately30.0% of the HCWs reported incidences of fever and pain and swelling at the injection site. Moreover,32.8% of the HCWs knew that the risk of developing adverse reactions increases when the 4CMenB vaccine is co-administered with other vaccines. Overall, all of the HCWs were convinced that vaccinations are an important instrument for preventing infectious diseases, and they were aware of their central role in promoting the 4CmenB vaccination and their need to be better informed.

Impact of pre-hospital antibiotic therapy on mortality in invasive meningococcal disease: a propensity score study

The role of pre-hospital antibiotic therapy in invasive meningococcal diseases remains unclear with contradictory data. The aim was to determine this role in the outcome of invasive meningococcal disease. Observational cohort study of patients with/without pre-hospital antibiotic therapy in invasive meningococcal disease attended at the Hospital Universitari de Bellvitge (Barcelona) during the period 1977-2013. Univariate and multivariate analyses of mortality, corrected by propensity score used as a covariate to adjust for potential confounding, were performed. Patients with pre-hospital antibiotic therapy were also analyzed according to whether they had received oral (group A) or parenteral antibiotics (early therapy) (group B). Five hundred twenty-seven cases of invasive meningococcal disease were recorded and 125 (24%) of them received pre-hospital antibiotic therapy. Shock and age were the risk factors independently related to mortality. Mortality differed between patients with/without pre-hospital antibiotic therapy (0.8% vs. 8%, p = 0.003). Pre-hospital antibiotic therapy seemed to be a protective factor in the multivariate analysis of mortality (p = 0.038; OR, 0.188; 95% CI, 0.013-0.882). However, it was no longer protective when the propensity score was included in the analysis (p = 0.103; OR, 0.173; 95% CI, 0.021-1.423). Analysis of the oral and parenteral pre-hospital antibiotic groups revealed that there were no deaths in early therapy group. Patients able to receive oral antibiotics had less severe symptoms than those who did not receive pre-hospital antibiotics. Age and shock were the factors independently related to mortality. Early parenteral therapy was not associated with death. Oral antibiotic therapy in patients able to take it was associated with a beneficial effect in the prognosis of invasive meningococcal disease.

Invasive Meningococcal Disease: What We Should Know, Before It Comes Back

Background

Invasive meningococcal disease (IMD), sepsis and/or meningitis continues to be a public health problem, with mortality rates ranging from 5% to 16%. The aim of our study was to further knowledge about IMD with a large series of cases occurring over a long period of time, in a cohort with a high percentage of adult patients.

Methods

Observational cohort study of patients with IMD between 1977 hand 2013 at our hospital, comparing patients with only sepsis and those with meningitis and several degrees of sepsis. The impact of dexamethasone and prophylactic phenytoin was determined, and an analysis of cutaneous and neurological sequelae was performed.

Results

A total of 527 episodes of IMD were recorded, comprising 57 cases of sepsis (11%) and 470 of meningitis with or without sepsis (89%). The number of episodes of IMD decreased from 352 of 527 (67%) in the first to 20 of 527 (4%) in the last quarter (P < .001). Thirty-three patients died (6%): 8 with sepsis (14%) and 25 with meningitis (5%) (P = .02). Cutaneous and neurological sequelae were present in 3% and 5% of survivors of sepsis and meningitis, respectively. The use of dexamethasone was safe and resulted in less arthritis, and patients given prophylactic phenytoin avoided seizures.

Conclusions

The frequency of IMD has decreased sharply since 1977. Patients with sepsis only have the highest mortality and complication rates, dexamethasone use is safe and can prevent some arthritis episodes, and prophylactic phenytoin might be useful in a selected population. A rapid response and antibiotic therapy may help improve the prognosis.

Invasive meningococcal disease: Impact of short course therapy. A DOOR/RADAR study

BACKGROUND

Invasive meningococcal disease is a severe infection. The appropriate duration of antibiotic therapy is not well established.

METHODS

Two hundred and sixty-three consecutive patients with invasive meningococcal disease treated with 4 days' antibiotic therapy were compared with 264 consecutive patients treated previously at the same center with 7 days' antibiotic therapy. A Desirability of Outcome Ranking (DOOR) and Response Adjusted for Duration of Antibiotic Risk (RADAR) study was also performed.

RESULTS

No relapses were recorded in any patient. Patients on the 4-day course were 63% female, with a median age of 23 years old (IQR 16-54) and patients on the 7-day course were 61% female, with a median age of 17 years old (IQR 12-43). Case fatality rate was 7% in the 4-d patients and 6% in the 7-d patients (p = 0.582). Neurological sequelae were recorded in 6% of the 4-d group and in 7% of the 7-d group ((p = 0.509) and cutaneous sequelae in 3% in both groups. There were no statistical significant differences between the groups in terms of clinical characteristics, laboratory findings or complications. The probability that a patient had a randomly chosen DOOR better with the 4-day regimen than with the 7-day regimen was 80.4% [95% CI 80.1-80.7%].

CONCLUSION

Invasive meningococcal disease may be successfully treated with a four-day course of antibiotic therapy without relapses.

Self Mutilating Behaviour in Severe Meningococcal Infection; An Interesting Association

Neisseria meningitidis most commonly manifests as asymptomatic colonization in the nasopharynx of healthy adolescents and adults. It may rarely present as invasive disease which may be either bacterial meningitis or meningococcal septicaemia. Hereby we report a case presented with fever and rashes, irritability followed by self mutilating behaviour who was diagnosed as a case of invasive meningococcal infection. He responded well to treatment with intravenous ceftriaxone and self mutilating behaviour was subsided completely after treatment. Necrosed tissues of fingers were amputated. With best of our knowledge, no similar case of self-mutilation associated with meningococcal infection has been reported yet.

[Vaccination against meningococcal B disease. Public statement of the Advisory Committee on Vaccines of the Spanish Association of Paediatrics (CAV-AEP)]

Meningococcal invasive disease, including the main clinical presentation forms (sepsis and meningitis), is a severe and potentially lethal infection caused by different serogroups of Neisseria meningitidis. Meningococcal serogroup B is the most prevalent in Europe. Most cases occur in children, with a mortality rate of 10% and a risk of permanent sequelae of 20-30% among survivors. The highest incidence and case fatality rates are observed in healthy children under 2-3 years old, followed by adolescents, although it can occur at any age. With the arrival in Spain of the only available vaccine against meningococcus B, the Advisory Committee on Vaccines of the Spanish Association of Paediatrics has analysed its preventive potential in detail, as well as its peculiar administrative situation in Spain. The purpose of this document is to publish the statement of the Committee as regards this vaccination and the access to it by the Spanish population, taking into account that it has been only authorized for people at risk. The vaccine is available free in the rest of Europe for those who want to acquire it, and in some countries and regions it has been introduced into the systematic immunisation schedules. The Committee considers that Bexsero® has a profile of a vaccine to be included in the official schedules of all the Spanish autonomous communities and insists on the need for it to be available in pharmacies for its administration in all children older than 2 months.

The role of CRISPR-Cas systems in virulence of pathogenic bacteria

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) genes are present in many bacterial and archaeal genomes. Since the discovery of the typical CRISPR loci in the 1980s, well before their physiological role was revealed, their variable sequences have been used as a complementary typing tool in diagnostic, epidemiologic, and evolutionary analyses of prokaryotic strains. The discovery that CRISPR spacers are often identical to sequence fragments of mobile genetic elements was a major breakthrough that eventually led to the elucidation of CRISPR-Cas as an adaptive immunity system. Key elements of this unique prokaryotic defense system are small CRISPR RNAs that guide nucleases to complementary target nucleic acids of invading viruses and plasmids, generally followed by the degradation of the invader. In addition, several recent studies have pointed at direct links of CRISPR-Cas to regulation of a range of stress-related phenomena. An interesting example concerns a pathogenic bacterium that possesses a CRISPR-associated ribonucleoprotein complex that may play a dual role in defense and/or virulence. In this review, we describe recently reported cases of potential involvement of CRISPR-Cas systems in bacterial stress responses in general and bacterial virulence in particular.

Fever in the pediatric patient

Fever is the most common reason that children and infants are brought to emergency departments. Emergency physicians face the challenge of quickly distinguishing benign from life-threatening conditions. The management of fever in children is guided by the patient's age, immunization status, and immune status as well as the results of a careful physical examination and appropriate laboratory tests and radiographic views. In this article, the evaluation and treatment of children with fevers of known and unknown origin are described. Causes of common and dangerous conditions that include fever in their manifestation are also discussed.

Use of MenACWY-CRM in adolescents in the United States

Adolescents constitute a high-risk group for invasive meningococcal disease. MenACWY-CRM (Menveo, Novartis Vaccines, Cambridge, MA) is a quadrivalent meningococcal conjugate vaccine indicated to prevent invasive meningococcal disease caused by Neisseria meningitidis serogroups A, C, W-135, and Y. It has been approved for use in persons age 2-55 years. The tolerability and immunogenicity of MenACWY-CRM in adolescents have been ascertained in phase 2 and 3 trials against MPSV4 (Menomune, sanofi pasteur, Swiftwater, PA), an unconjugated quadrivalent meningococcal vaccine, and MenACWY-D (Menactra, sanofi pasteur), another conjugated quadrivalent meningococcal vaccine. Clinical trials also have demonstrated that MenACWY-CRM is well tolerated and immunogenic when administered to adolescents concomitantly with the combined tetanus, diphtheria, and acellular pertussis vaccine (Boostrix, GlaxoSmithKline Biologicals, Rixensart, Belgium) and the quadrivalent human papillomavirus vaccine (Gardasil, Merck & Co., Inc., Whitehouse Station, NJ).

Factors that influence parental vaccination decisions for adolescents, 13 to 17 years old: National Immunization Survey-Teen, 2010

OBJECTIVES

We aim to describe factors that influence parental decisions to vaccinate their adolescents.

METHODS

Data from the July to December 2010 National Immunization Survey-Teen Parental Concerns Module were analyzed to determine factors that influence parental decisions to vaccinate their adolescents.

RESULTS

Parents reported that their adolescent's health care provider recommended tetanus toxoid/tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Td/Tdap; 74.4%), meningococcal conjugate (MenACWY; 60.3%), and human papillomavirus (HPV; 71.3%). Vaccination coverage estimates were significantly higher among parents who reported receiving a provider recommendation: 85.2% versus 76.7% (Td/Tdap), 77.3% versus 49.7% (MenACWY), and 62.2% versus 21.5% (HPV). Compared with Td/Tdap and MenACWY, fewer HPV vaccination conversations included recommendations for vaccination. Other than health care providers, school requirements (46.1%), news coverage (31.2%), and family (31.0%) were most frequently reported influences on parental vaccination decisions.

CONCLUSIONS

Many factors influence parental decisions to vaccinate their adolescents; one of the most important factors is the provider recommendation. Missed opportunities for vaccination persist when strong vaccination recommendations are not given or are delayed.

Sputum microbiota in tuberculosis as revealed by 16S rRNA pyrosequencing

Background

Tuberculosis (TB) remains a global threat in the 21st century. Traditional studies of the disease are focused on the single pathogen Mycobacterium tuberculosis. Recent studies have revealed associations of some diseases with an imbalance in the microbial community. Characterization of the TB microbiota could allow a better understanding of the disease.

Methodology/Principal Findings

Here, the sputum microbiota in TB infection was examined by using 16S rRNA pyrosequencing. A total of 829,873 high-quality sequencing reads were generated from 22 TB and 14 control sputum samples. Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria, and Fusobacteria were the five major bacterial phyla recovered, which together composed over 98% of the microbial community. Proteobacteria and Bacteroidetes were more represented in the TB samples and Firmicutes was more predominant in the controls. Sixteen major bacterial genera were recovered. Streptococcus, Neisseria and Prevotella were the most predominant genera, which were dominated by several operational taxonomic units grouped at a 97% similarity level. Actinomyces, Fusobacterium, Leptotrichia, Prevotella, Streptococcus, and Veillonella were found in all TB samples, possibly representing the core genera in TB sputum microbiota. The less represented genera Mogibacterium, Moryella and Oribacterium were enriched statistically in the TB samples, while a genus belonging to the unclassified Lactobacillales was enriched in the controls. The diversity of microbiota was similar in the TB and control samples.

Conclusions/Significance

The composition and diversity of sputum microbiota in TB infection was characterized for the first time by using high-throughput pyrosequencing. It lays the framework for examination of potential roles played by the diverse microbiota in TB pathogenesis and progression, and could ultimately facilitate advances in TB treatment.

Importance of circulating antibodies in protection against meningococcal disease

Neisseria meningitidis infection results in life-threatening illnesses, including bacteremia, sepsis and meningitis. Early diagnosis and treatment are a challenge due to rapid disease progression, resulting in high mortality and morbidity in survivors. Disease can occur in healthy individuals, however, risk of infection is higher in patients with certain risk factors. N meningitidis carriage and case-fatality rates are high in adolescents and young adults. The absolute incidence of meningococcal disease has decreased partially due to increasing meningococcal vaccination rates. Maintaining protective levels of circulating antibodies by vaccination is necessary for clinical protection against disease. The Centers for Disease Control and Prevention Advisory Committee on Immunization Practices guidelines recommend vaccination for all individuals aged 11 through 12 years, followed by a booster dose at age 16 years for maintenance of protective antibody levels throughout the high-risk years. Despite these guidelines, many adolescents remain unvaccinated and susceptible to infection and disease. 

Consensus recommendation for meningococcal disease prevention in children and adolescents in the Middle East region

Facing the availability of the new generation of quadrivalent meningococcal conjugate vaccines (Menveo®, Menactra® and others pending for license) and their recent implementation in Saudi Arabia, experts from 11 countries of the Middle East region met at a “Meningococcal Leadership Forum” (MLF), which took place in May 2010 in Dubai. The participants of the conference discussed the importance of introducing the concept of conjugate vaccines – especially for children and adolescents – and elaborated a consensus recommendation to support healthcare professionals and decision makers with their expertise. In experts’ opinion, conjugate vaccines are the best choice for the prevention of meningococcal disease caused by serogroups A, C, W-135 and Y. As quadrivalent meningococcal conjugate vaccines are registered and available in the Middle East region, they should replace plain polysaccharide vaccines and be integrated in pediatric and adolescent vaccination schedules, including infant vaccination concomitantly with basic EPI vaccines when licensed.

Critical appraisal of a quadrivalent CRM(197) conjugate vaccine against meningococcal serogroups A, C W-135 and Y (Menveo) in the context of treatment and prevention of invasive disease

Worldwide, invasive meningococcal disease affects about 500,000 people annually. Case fatality in developed countries averages 10%, and higher rates are reported in less prosperous regions. According to the World Health Organization, the most important pathogenic serogroups are A, B, C, W-135, X, and Y. Clinical features of invasive meningococcal disease make diagnosis and management difficult. Antibiotic measures are recommended for prophylaxis after exposure and for treatment of invasive meningococcal disease cases; however, resistant strains may be emerging. Vaccines are generally regarded as the best preventative measure for invasive meningococcal disease. Polysaccharide vaccines against serogroups A, C, W-135, and Y using protein conjugation technology have clear advantages over older plain polysaccharide formulations without a protein component. The first quadrivalent meningococcal conjugate vaccine (MenACWY-D) was licensed in the US in 2005. More recently, MenACWY-CRM (Menveo^®) was licensed in Europe, the US, the Middle East, and Latin America. MenACWY-CRM uses cross-reactive material 197, a nontoxic mutant of diphtheria toxin, as the carrier protein. MenACWY-CRM offers robust immunogenicity in all age groups, with a tolerability profile similar to that of a plain polysaccharide vaccine. Given its potential for protecting persons from infancy to old age, MenACWY-CRM offers the opportunity to protect broad populations against invasive meningococcal disease. The most optimal strategy for use of the vaccine has to be assessed country by country on the basis of local epidemiology, individual health care systems, and need.

Meningococcal disease: early recognition is vital to patient outcomes

Since the development of vaccines to prevent Haemophilus influenzae type b and Streptococcus pneumoniae, Neisseria meningitidis is the leading cause of bacterial meningitis in the United States. Education of healthcare professionals to improve identification and provide immediate treatment of patients with symptoms consistent with meningococcal disease will result in improved outcomes.