Paediatric meningitis in the conjugate vaccine era and a novel clinical decision model to predict bacterial aetiology.

OBJECTIVES: The aims of this study were to assess aetiology and clinical characteristics in childhood meningitis, and develop clinical decision rules to distinguish bacterial meningitis from other similar clinical syndromes. METHODS: Children aged <16 years hospitalised with suspected meningitis/encephalitis were included, and prospectively recruited at 31 UK hospitals. Meningitis was defined as identification of bacteria/viruses from cerebrospinal fluid (CSF) and/or a raised CSF white blood cell count. New clinical decision rules were developed to distinguish bacterial from viral meningitis and those of alternative aetiology. RESULTS: The cohort included 3002 children (median age 2·4 months); 1101/3002 (36·7%) had meningitis, including 180 bacterial, 423 viral and 280 with no pathogen identified. Enterovirus was the most common pathogen in those aged <6 months and 10-16 years, with Neisseria meningitidis and/or Streptococcus pneumoniae commonest at age 6 months to 9 years. The Bacterial Meningitis Score had a negative predictive value of 95·3%. We developed two clinical decision rules, that could be used either before (sensitivity 82%, specificity 71%) or after lumbar puncture (sensitivity 84%, specificity 93%), to determine risk of bacterial meningitis. CONCLUSIONS: Bacterial meningitis comprised 6% of children with suspected meningitis/encephalitis. Our clinical decision rules provide potential novel approaches to assist with identifying children with bacterial meningitis. FUNDING: This study was funded by the Meningitis Research Foundation, Pfizer and the NIHR Programme Grants for Applied Research.

Differences in meningococcal disease incidence by health insurance type and among persons experiencing homelessness-United States, 2016-2019.

Meningococcal disease is a serious but rare disease in the United States. Prior publications suggest incidence differs among privately vs publicly-insured persons, and that incidence is higher among persons experiencing homelessness (PEH) than persons not known to be experiencing homelessness (non-PEH). Using insurance claims data for persons aged <1 to 64 years, we calculated meningococcal disease incidence among a population with employer-sponsored commercial insurance and persons enrolled in state Medicaid programs nationwide. We also examined meningococcal disease incidence by PEH status in Medicaid data. From 2016 through 2019, persons who met our study inclusion criteria contributed a total of 84,460,548 person-years (PYs) to our analysis of commercial insurance data and 253,496,622 PYs to our analysis of Medicaid data. Incidence was higher among persons enrolled in Medicaid (0.12 cases per 100,000 PYs) than persons with commercial insurance (0.06 cases per 100,000 PYs). Incidence was 3.17 cases per 100,000 PYs among PEH in Medicaid, 27 times higher than among non-PEH in Medicaid. Understanding the underlying drivers of the higher meningococcal disease incidence among PEH and persons enrolled in Medicaid may inform prevention strategies for populations experiencing a higher burden of disease.

Review of the epidemiology, diagnosis and management of invasive meningococcal disease in Vietnam.

Invasive meningococcal disease (IMD), caused by Neisseria meningitidis, is life-threatening with a high case fatality rate (CFR) and severe sequelae. We compiled and critically discussed the evidence on IMD epidemiology, antibiotic resistance and disease management in Vietnam, focusing on children. PubMed, Embase and gray literature searches for English, Vietnamese and French publications, with no date restrictions, retrieved 11 eligible studies. IMD incidence rate (/100,000 population) was 7.4 [95% confidence interval 3.6-15.3] in children under 5 years of age; driven by high rates in infants (e.g. 29.1 [8.0-106.0] in 7-11 month-olds). Serogroup B IMD was predominant. Neisseria meningitidis strains may have developed resistance to streptomycin, sulfonamides, ciprofloxacin, and possibly ceftriaxone. There was a lack of current data on diagnosis and treatment of IMD, which remain challenging. Healthcare professionals should be trained to rapidly recognize and treat IMD. Preventive measures, such as routine vaccination, could help address the medical need.

Evaluation of the World Health Organization Global Invasive Bacterial Vaccine-Preventable Disease (IB-VPD) Surveillance Network's Laboratory External Quality Assessment Programme, 2014-2019.

Introduction. In 2009, the World Health Organization (WHO) established the Global Invasive Bacterial Vaccine Preventable Disease (IB-VPD) Surveillance Network (GISN) to monitor the global burden and aetiology of bacterial meningitis, pneumonia and sepsis caused by Haemophilus influenzae (Hi), Neisseria meningitidis (Nm) and Streptococcus pneumoniae (Sp).Hypothesis/Gap Statement. The GISN established an external quality assessment (EQA) programme for the characterization of Hi, Nm and Sp by culture and diagnostic PCR.Aim. To assess the performance of sentinel site laboratories (SSLs), national laboratories (NLs) and regional reference laboratories (RRLs) between 2014 and 2019 in the EQA programme.Methodology. Test samples consisted of bacterial smears for Gram-staining, viable isolates for identification and serotyping or serogrouping (ST/SG), plus simulated cerebrospinal fluid (CSF) samples for species detection and ST/SG by PCR. SSLs and NLs were only required to analyse the slides for Gram staining and identify the species of the live isolates. RRLs, and any SLs and NLs that had the additional laboratory capacity, were also required to ST/SG the viable isolates and analyse the simulated CSF samples.Results. Across the period, 69-112 SS/NL labs and eight or nine RRLs participated in the EQA exercise. Most participants correctly identified Nm and Sp in Gram-stained smears but were less successful with Hi and other species. SSLs/NLs identified the Hi, Nm and Sp cultures well and also submitted up to 56 % of Hi, 62 % of Nm and 33 % of Sp optional ST/SG results each year. There was an increasing trend in the proportion of correct results submitted over the 6 years for Nm and Sp. Some SSLs/NLs also performed the optional detection and ST/SG of the three organisms by PCR in simulated CSF from 2015 onwards; 89-100 % of the CSF samples were correctly identified and 76-93 % of Hi-, 90-100 % of Nm- and 75-100 % of Sp-positive samples were also correctly ST/SG across the distributions. The RRLs performed all parts of the EQA to a very high standard, with very few errors across all aspects of the EQA.Conclusion. The EQA has been an important tool in maintaining high standards of laboratory testing and building of laboratory capacity in the GISN.

Accurate, fast and cost-effective simultaneous detection of bacterial meningitis by qualitative PCR with high-resolution melting.

Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae are leading causes of meningitis and acute invasive infections. PCR-based methods are widely used for the diagnosis and surveillance of bacterial pathogens because of their high sensitivity, specificity and high-throughput capabilities compared with conventional laboratory methods. This study evaluated a high-resolution melting qualitative PCR analysis method for the simultaneous detection of these three pathogens. The assay has been optimized to detect three species-specific genes of each organism isolated from clinical samples, enabling accurate identification of the etiological agent. The method proved to be highly sensitive and cheaper than the real-time PCR TaqMan® system because it is probe-free; it could be used for the diagnosis of invasive diseases in public health laboratories of developing countries.

Accounting for Adverse Events Following Immunization in Economic Evaluation: Systematic Review of Economic Evaluations of Pediatric Vaccines Against Pneumococcus, Rotavirus, Human Papillomavirus, Meningococcus and Measles-Mumps-Rubella-Varicella.

OBJECTIVES: Economic evaluations of vaccines should accurately represent all relevant economic and health consequences of vaccination, including losses due to adverse events following immunization (AEFI). We investigated to what extent economic evaluations of pediatric vaccines account for AEFI, which methods are used to do so and whether inclusion of AEFI is associated with study characteristics and the vaccine's safety profile. METHODS: A systematic literature search (MEDLINE, EMBASE, Cochrane Systematic Reviews and Trials, Database of the Centre for Reviews and Dissemination of the University of York, EconPapers, Paediatric Economic Database Evaluation, Tufts New England Cost-Effectiveness Analysis Registry, Tufts New England Global Health CEA, International Network of Agencies for Health Technology Assessment Database) was performed for economic evaluations published between 2014 and 29 April 2021 (date of search) pertaining to the five groups of pediatric vaccines licensed in Europe and the United States since 1998: the human papillomavirus (HPV) vaccines, the meningococcal vaccines (MCV), the measles-mumps-rubella-varicella (MMRV) combination vaccines, the pneumococcal conjugate vaccines (PCV) and the rotavirus vaccines (RV). Rates of accounting for AEFI were calculated, stratified by study characteristics (e.g., region, publication year, journal impact factor, level of industry involvement) and triangulated with the vaccine's safety profile (Advisory Committee on Immunization Practices [ACIP] recommendations and information on safety-related product label changes). The studies accounting for AEFI were analyzed in terms of the methods used to account for both cost and effect implications of AEFI. RESULTS: We identified 112 economic evaluations, of which 28 (25%) accounted for AEFI. This proportion was significantly higher for MMRV (80%, four out of five evaluations), MCV (61%, 11 out of 18 evaluations) and RV (60%, nine out of 15 evaluations) compared to HPV (6%, three out of 53 evaluations) and PCV (5%, one out of 21 evaluations). No other study characteristics were associated with a study's likelihood of accounting for AEFI. Vaccines for which AEFI were more frequently accounted for also had a higher frequency of label changes and a higher level of attention to AEFI in ACIP recommendations. Nine studies accounted for both the cost and health implications of AEFI, 18 studies considered only costs and one only health outcomes. While the cost impact was usually estimated based on routine billing data, the adverse health impact of AEFI was usually estimated based on assumptions. DISCUSSION: Although (mild) AEFI were demonstrated for all five studied vaccines, only a quarter of reviewed studies accounted for these, mostly in an incomplete and inaccurate manner. We provide guidance on which methods to use to better quantify the impact of AEFI on both costs and health outcomes. Policymakers should be aware that the impact of AEFI on cost-effectiveness is likely to be underestimated in the majority of economic evaluations.

Equity of the Meningitis B vaccination programme in England, 2016-2018.

In England, the Meningitis B (MenB) vaccine is scheduled at eight and 16 weeks with a booster dose at one year of age and protects children against invasive bacterial meningococcal disease caused by Neisseria meningitidis serogroup B. Coverage of the second dose of MenB vaccine at 12 months was >92% in 2017/18, but this may mask inequalities in coverage in particular population groups. MenB vaccination records for children aged six, 12 and 18 months of age from December 2016 to May 2018 were routinely extracted from GP patient management systems every month in England via a web-based platform for national monitoring of vaccine coverage. We determined the association between ethnicity, deprivation and area of residence, vaccine coverage and drop-out rates (between dose one and dose two), using binomial regression. After adjusting for other factors, ethnic groups with lowest dose one coverage (Black or Black British-Caribbean, White-Any other White background, White-Irish) also had lowest dose two coverage, but in addition, these ethnic groups also had the largest drop-out rates between dose one and dose two. The drop-out rate for Black or Black British-Caribbean children was 5.7 percentage points higher than for White-British children. Vaccine coverage decreased with increasing deprivation quintile, and this was most marked for the booster coverage (6.2 percentage points lower in the most deprived compared to least deprived quintile, p < 0.001). To achieve high coverage for completed courses across all ethnic groups and deprivation quintiles both high initiation rates and a reduction in drop-out rates for ethnic groups with lowest coverage is necessary. A qualitative approach to better understand reasons behind lower coverage and higher drop-out rates in the most underserved ethnic groups is required to develop tailored approaches addressing these inequalities.

Public health impact and cost-effectiveness of gonorrhoea vaccination: an integrated transmission-dynamic health-economic modelling analysis.

BACKGROUND: Gonorrhoea is a rapidly growing public health threat, with rising incidence and increasing drug resistance. Evidence that the MeNZB and four-component serogroup B meningococcal (4CMenB) vaccines, designed against Neisseria meningitidis, can also offer protection against gonorrhoea has created interest in using 4CMenB for this purpose and for developing gonorrhoea-specific vaccines. However, cost-effectiveness, and how the efficacy and duration of protection affect a gonorrhoea vaccine's value, have not been assessed. METHODS: We developed an integrated transmission-dynamic health-economic model, calibrated using Bayesian methods to surveillance data (from the Genitourinary Medicine Clinic Activity Dataset and the Gonococcal Resistance to Antimicrobials Surveillance Programme) on men who have sex with men (MSM) in England. We considered vaccination of MSM from the perspective of sexual health clinics, with and without vaccination offered to all adolescents in schools (vaccination before entry [VbE]), comparing three realistic approaches to targeting: vaccination on attendance (VoA) for testing; vaccination on diagnosis (VoD) with gonorrhoea; or vaccination according to risk (VaR), offered to patients diagnosed with gonorrhoea plus individuals who test negative but report having more than five sexual partners per year. For the primary analysis, vaccine impact was assessed relative to no vaccination in a conservative baseline scenario wherein time-varying behavioural parameters (sexual risk behaviour and screening rates) stabilise. To calculate the value of vaccination per dose administered, the value of vaccination was calculated by summing the averted costs of testing and treatment, and the monetary value of quality-adjusted life-year (QALY) gains with a QALY valued at £20 000. Costs were in 2018-19 GB£, and both costs and QALYs were discounted at 3·5% per year. We analysed the effects of varying vaccine uptake (0·5, 1, or 2 times HPV vaccine uptake by MSM in sexual health clinics in England), vaccine efficacy (1-100%) and duration of protection (1-20 years), and the time-horizon considered (10 years and 20 years). In addition, we calculated incremental cost-effectiveness ratios for the use of 4CMenB using assumed vaccine prices. FINDINGS: VbE has little impact on gonorrhoea diagnoses, with only 1·7% of MSM vaccinated per year. VoA has the largest impact but requires more vaccine doses than any other strategy, whereas VoD has a moderate impact but requires many fewer doses than VoA. VaR has almost the same impact as VoA but with fewer doses administered than VoA. VaR is the most cost-effective strategy for vaccines of moderate efficacy or duration of protection (or both), although VoD is more cost-effective for very protective and long-lasting vaccines. Even under conservative assumptions (efficacy equivalent to that of MeNZB and protection lasting for 18 months after two-dose primary vaccination and 36 months after single-dose booster vaccination), 4CMenB administered under VaR would likely be cost-saving at its current National Health Service price, averting an estimated mean 110 200 cases (95% credible interval 36 500-223 600), gaining a mean 100·3 QALYs (31·0-215·8), and saving a mean £7·9 million (0·0-20·5) over 10 years. A hypothetical gonorrhoea vaccine's value is increased more by improving its efficacy than its duration of protection-eg, 30% protection lasting 2 years has a median value of £48 (22-85) per dose over 10 years; doubling efficacy increases the value to £102 (53-144) whereas doubling the duration of protection increases it to £72 (34-120). INTERPRETATION: We recommend that vaccination of MSM against gonorrhoea according to risk in sexual health clinics in England with the 4CMenB vaccine be considered. Development of gonorrhoea-specific vaccines should prioritise maximising efficacy over duration of protection. FUNDING: Medical Research Council (UK), National Institute for Health Research (UK).

Epidemiology and economic burden of meningococcal disease in Germany: A systematic review.

INTRODUCTION: Invasive meningococcal disease (IMD) is a notifiable disease in Germany and other European countries. Due to the high lethality of the disease and the risk of long-term consequences, IMD prevention is of high public health relevance despite the low number of cases in the population. This study aims to describe key epidemiological and economic parameters of IMD in Germany to support national decision-making processes for implementing enhanced prevention measures. METHODS: Based on a systematic literature review in PubMed and EMBASE, all publications on the burden of disease and costs of IMD published up to May 2020 were evaluated. Additionally, notification data were used to report the annual case numbers and incidence of IMD in Germany until the end of 2019. RESULTS: Thirty-six studies were included, of which 35 reported data on the epidemiological burden of disease and three reported data on economic aspects of IMD. The type of reported endpoints and results on the incidence of IMD differed widely by reporting year, population, and data source used. Most of the data are reported without specific information about a serogroup. Data on the economic burden of disease and healthcare resource use are scarce. Based on mandatory notification data, a decrease in the incidence of notified IMD cases has been observed since 2004. Currently, the nationwide annual incidence in Germany is at 0.3 cases per 100,000 persons and has gradually decreased. While the overall decline is mainly attributable to MenB, cases with MenY and MenW are the only ones that have increased on a low level in recent years. CONCLUSION: While IMD is a rare disease, high direct and indirect costs illustrate the relevance of the disease for patients, caregivers, as well as for the health care system. Future research should concentrate on quantifying the long-term economic burden and indirect costs of meningococcal disease. Integrated IMD surveillance with isolate characterisation remains crucial to inform public health policies.

Cost of illness of invasive meningococcal disease caused by serogroup B Neisseria meningitidis in Spain.

INTRODUCTION: Invasive meningococcal disease (IMD) is a severe infectious disease, mainly affecting children under 5 years, associated with long-term physical, neurological and psychological sequelae. In Spain, most IMD cases are caused by meningococcal serogroup B (MenB). This study estimates its economic burden from a societal perspective in Spain. METHODS: A previously published bottom-up, model-based incidence costing approach by Scholz et al. (2019) to estimate the economic burden of MenB in Germany was adapted to the Spanish setting. Diagnosis and age-related costs for a hypothetical Spanish cohort were calculated over a lifetime horizon. Official Spanish databases, literature and expert opinion were used as data sources. The costs were updated to 2019 prices, and a 3% discount rate was applied. Direct costs related to the acute IMD phase, long-term sequelae, rehabilitation and public health response were considered. Indirect costs included productivity losses and premature mortality and were calculated using the human-capital approach (HCA) and friction-cost approach (FCA). Deterministic and probabilistic sensitivity analyses were also performed. RESULT: At base-case, the total cost for a cohort of 142 patients (2017-2018 period) was €4.74 million (€33,484/case) using the FCA and €13.14 million (€92,768/case) using the HCA. Direct costs amounted to €4.65 million (€32,765/case). Sequelae costs represented 62.46% of the total cost using the FCA and 77.63% using the HCA. Deterministic sensitivity analysis showed that variation of ± 20% in the input parameter values (population, epidemiology, productivity, costs) had the greatest influence on the base-case results, and the probabilistic sensitivity analysis showed the probability of fitting base-case estimates was > 99%, both for FCA and HCA. DISCUSSION: MenB IMD is an uncommon but severe disease, with a high economic burden for Spanish society. The elevated costs per IMD case reflect its severity in each patient suffering this disease, especially due to the development of sequelae.

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 burden of meningococcal meningitis in the African Meningitis Belt, from 2009 to 2014: a trend analysis.

INTRODUCTION: Neisseria meningitides is the leading cause of meningitis in the African Meningitis Belt. The objective of this study was to conduct a trend analysis of the burden of meningococcal meningitis in the African Meningitis Belt countries from 2009 to 2014. METHODS: secondary data on incidence and death cases were collected from the World Health Organization (WHO) and analyzed to determine the trends of meningitis in the African Meningitis Belt countries using Microsoft excel and Stata 14. RESULTS: these data show unstable meningococcal meningitis outbreaks in the Meningitis Belt before and after the introduction of meningococcal A vaccine (MenAfriVac). The vaccine was introduced at different times in the different countries. E.g. it was introduced in 2010 across Burkina Faso, Mali and Niger while it was introduced from 2011 to 2016 in other countries through mass campaigns. Ever since the vaccine was introduced, there has been a decrease in the number of cases in the countries hence a reduction in the burden of the disease. CONCLUSION: after the introduction of the MenAfriVac, there has been a decline in the meningitis cases in Benin, Burkina Faso, Chad, Ghana, Niger and Nigeria while Sudan shows a decrease only in 2014.

Factors Associated With Receipt of Meningococcal B Vaccine Among United States Adolescents, National Immunization Survey-Teen, 2017-2018.

PURPOSE: In this study, we evaluated factors associated with receipt of meningococcal serogroup B (MenB) vaccine among adolescents in the United States. METHODS: We used public use data files from the National Immunization Survey-Teen from 2017 to 2018. Logistic regression was used to model associations among sociodemographic, healthcare, and vaccination variables of interest and MenB vaccine receipt (≥1 vs. 0 dose). To explore associations between state-level meningococcal vaccination requirements and MenB vaccine uptake, we performed a secondary analysis stratified by presence of a quadrivalent meningococcal (MenACWY) vaccination requirement for secondary school attendance in the adolescent's state of residence (no requirement vs. a one- or two-dose requirement). RESULTS: Among 7,288 adolescents, MenB vaccine receipt was significantly associated with up-to-date human papillomavirus (adjusted odds ratio [aOR] 1.74, 95% confidence interval [CI] 1.29-2.35) and MenACWY (aOR 5.81, 95% CI 4.14-8.13) vaccination status in multivariable analysis. Adolescents with private insurance were less likely to be vaccinated (aOR .61, 95% CI .46-.79) compared to adolescents with other health insurance types. In secondary analyses, health insurance was no longer significantly associated with MenB vaccine uptake among adolescents in states with a MenACWY requirement. CONCLUSIONS: We found that MenB vaccination is associated with receipt of other vaccines recommended for use in adolescents. Adolescents with private health insurance were less likely to be vaccinated against MenB, although state MenACWY requirements appeared to modify the effect of insurance on MenB vaccine receipt. Further work to understand how these factors may influence delivery and acceptance of MenB vaccine can inform interventions and strategies to improve uptake.

Development of a simple and cost-effective gel-based duplex PCR method to identify both encapsulated and unencapsulated Neisseria meningitidis applicable under resource-limited conditions.

Tens of thousands of cases of invasive meningococcal diseases (IMD) with thousands of deaths are reported annually worldwide; however, only approximately 40 cases occur each year in Japan. Therefore, the majority of medical technologists in Japan have never performed or prepared for analyses of the causative agent, Neisseria meningitidis. Since IMD outbreaks have been reported at mass gathering events, the risk of IMD will increase in Japan in 2021 because of the Olympics. In the present study, we developed a new simple gel-based duplex PCR method that may be employed by the majority Japanese clinical laboratories. It is simple to perform and time- and cost-effectively identifies encapsulated and unencapsulated N. meningitidis by detecting the encapsulated N. meningitidis-specific ctrB and N. meningitidis-specific ggt genes. We consider this simple and cost-effective identification method to compensate for the lack of experience and resource-poor conditions in most Japanese laboratories in which N. meningitidis has rarely been examined.

Risk factors for invasive meningococcal disease: a retrospective analysis of the French national public health insurance database.

Vaccination of at-risk populations against Neisseria meningitidis is an important strategy to prevent invasive meningococcal disease (IMD). The objective of this study was to characterize preexisting risk factors in patients with IMD and to compare their relative importance. This case-control analysis was performed in the French national public health insurance database (SNDS). Cases consisted of all people hospitalized for IMD in France over a six-year period (2012-2017). Controls were matched by age, gender, and district of residence. Medical risk factors were identified from ICD-10 codes in the SNDS. Socioeconomic risk factors studied were low household income and social deprivation of the municipality of residence. Associations of these risk factors with hospitalization for IMD were quantified as odds ratios (ORs) between cases and controls with their 95% confidence intervals (95%CI). The medical risk factors showing the most robust associations were congenital immunodeficiency (OR: 39.1 [95%CI: 5.1-299], acquired immunodeficiency (10.3 [4.5-24.0]) and asplenia/hyposplenia (6.7 [3.7-14.7]). In addition, certain chronic medical conditions, such as autoimmune disorders (5.4 [2.5-11.8]), hemophilia (4.7 [1.8-12.2]) and severe chronic respiratory disorders (4.3 [3.1-6.2]) were also strongly associated, as was low household income (1.68 [1.49-1.80]). In conclusion, this study has documented potential risk factors associated with hospitalization for IMD in a large and comprehensive sample of individuals with IMD in France. Several of the risk factors identified may help identify groups who could benefit from targeted prevention measures (such as vaccination) in order to reduce the burden of IMD.

A pooled analysis of the LAMP assay for the detection of Neisseria meningitidis.

BACKGROUND: Neisseria meningitidis is a major cause of bacterial meningitis, and these infections are associated with a high mortality rate. Rapid and reliable diagnosis of bacterial meningitis is critical in clinical practice. However, this disease often occurs in economically depressed areas, so an inexpensive, easy to use, and accurate technology is needed. We performed a pooled-analysis to assess the potential of the recently developed loop-mediated isothermal amplification (LAMP) assay for detection of meningococcus. METHODS: Pubmed, Embase, and Web of Science were searched to identify original studies that used the LAMP assay to detect meningococcus. After pooling of data, the sensitivity and specificity were calculated, a summary receiver operating characteristic (SROC) curve was determined, and the area under the SROC curve was computed to determine diagnostic accuracy. Publication bias was assessed using Deek's funnel plot. RESULTS: We examined 14 studies within 6 publications. The LAMP assay had high sensitivity (94%) and specificity (100%) in the detection of meningococcus in all studies. The area under the SROC curve (0.980) indicated high overall accuracy of the LAMP assay. There was no evidence of publication bias. DISCUSSION: The LAMP assay has accuracy comparable to bacterial culture and PCR for detection of meningococcus, but is less expensive and easier to use. We suggest the adoption of the LAMP assay to detect meningococcus, especially in economically depressed areas.

Meningococcal carriage in Norwegian teenagers: strain characterisation and assessment of risk factors.

Teenagers have a higher risk of invasive meningococcal disease (IMD) than the general population. This cross-sectional study aimed to characterise strains of Neisseria meningitidis circulating among Norwegian teenagers and to assess risk factors for meningococcal carriage. Oropharyngeal swabs were collected from secondary-school students in southeastern Norway in 2018-2019. Meningococcal isolates were characterised using whole genome sequencing. Risk factors for meningococcal carriage were assessed from questionnaire data. Samples were obtained from 2296 12-24-year-olds (majority 13-19-year-olds). N. meningitidis was identified in 167 (7.3%) individuals. The highest carriage rate was found among 18-year-olds (16.4%). Most carriage isolates were capsule null (40.1%) or genogroup Y (33.5%). Clonal complexes cc23 (35.9%) and cc198 (32.3%) dominated and 38.9% of carriage strains were similar to invasive strains currently causing IMD in Norway. Use of Swedish snus (smokeless tobacco) (OR 1.56, 95% CI 1.07-2.27), kissing >two persons/month (OR 2.76, 95% CI 1.49-5.10) and partying >10 times/3months (OR 3.50, 95% CI 1.45-8.48) were associated with carriage, while age, cigarette smoking, sharing of drinking bottles and meningococcal vaccination were not. The high meningococcal carriage rate among 18-year-olds is probably due to risk-related behaviour. Use of Swedish snus is possibly a new risk factor for meningococcal carriage. Almost 40% of circulating carriage strains have invasive potential.

An assessment of the use of Hepatitis B Virus core protein virus-like particles to display heterologous antigens from Neisseria meningitidis.

Neisseria meningitidis is the causative agent of meningococcal meningitis and sepsis and remains a significant public health problem in many countries. Efforts to develop a comprehensive vaccine against serogroup B meningococci have focused on the use of surface-exposed outer membrane proteins. Here we report the use of virus-like particles derived from the core protein of Hepatitis B Virus, HBc, to incorporate antigen domains derived from Factor H binding protein (FHbp) and the adhesin NadA. The extracellular domain of NadA was inserted into the major immunodominant region of HBc, and the C-terminal domain of FHbp at the C-terminus (CFHbp), creating a single polypeptide chain 3.7-fold larger than native HBc. Remarkably, cryoelectron microscopy revealed that the construct formed assemblies that were able to incorporate both antigens with minimal structural changes to native HBc. Electron density was weak for NadA and absent for CFHbp, partly attributable to domain flexibility. Following immunization of mice, three HBc fusions (CFHbp or NadA alone, NadA + CFHbp) were able to induce production of IgG1, IgG2a and IgG2b antibodies reactive against their respective antigens at dilutions in excess of 1:18,000. However, only HBc fusions containing NadA elicited the production of antibodies with serum bactericidal activity. It is hypothesized that this improved immune response is attributable to the adoption of a more native-like folding of crucial conformational epitopes of NadA within the chimeric VLP. This work demonstrates that HBc can incorporate insertions of large antigen domains but that maintenance of their three-dimensional structure is likely to be critical in obtaining a protective response.

Clinical and economic burden of invasive meningococcal disease: Evidence from a large German claims database.

BACKGROUND: Limited data is available to describe clinical characteristics, long-term outcomes, healthcare resource use and the attributable costs of invasive meningococcal disease (IMD) in Germany. We aimed to examine demographic and clinical characteristics as well as healthcare resource use and related costs. METHODS: We conducted a retrospective cohort study based on the InGef database in patients with IMD between 2009 and 2015. Cases were identified based on hospital main discharge diagnoses of IMD. Demographics, clinical characteristics, 30-day and 1-year mortality as well as IMD-related complications and sequelae in IMD cases were examined. In addition, short and long-term costs and healthcare resource use in IMD cases were analyzed and compared to an age- and sex-matched control group without IMD. RESULTS: The study population comprised 164 IMD cases between 2009 and 2015. The mean length of the IMD-related hospitalization was 13 days and 38% of all cases presented with meningitis only, 35% with sepsis only, 16% with both and 11% with other IMD. The 30-day and one-year mortality were 4.3% and 5.5%, respectively. Approximately 13% of IMD cases had documented IMD-related complications at hospital discharge and 24% suffered from sequelae during follow-up. The IMD-related hospitalization was associated with mean costs of € 9,620 (standard deviation: € 22,197). The difference of mean costs between IMD cases and matched non-IMD controls were € 267 in the first month and € 1,161 from one month to one year after discharged from IMD-related hospitalization. During the later follow-up period, the mean overall costs and costs associated with individual healthcare sectors were also higher for IMD cases without reaching statistical significance. CONCLUSIONS: IMD resulted in severe complications and sequelae and was associated with extensive costs and increased healthcare resource use in Germany, especially in the first year after IMD diagnosis and due the IMD-related hospitalization.