Search Results (25)

Background: While efforts have been made to control meningococcal disease or carriage during mass gatherings (MGs), it is still a significant problem. This meta-analysis aims to assess the prevalence and predictors of meningitis carriage during MGs and travel. Methodology: PubMed, Scopus, Embase, and Cochrane were searched from their conception to January 2025. Cohort and cross-sectional studies assessing the prevalence of meningitis carriage and its serotype related to MGs and/or travel, and risk factors associated with its spread, were considered. The Newcastle–Ottawa scale was used for the quality assessment of studies. Results: Out of 1301 studies, 25 were considered for this meta-analysis. The largest geographic area involved was Saudi Arabia. A meta-analysis of 24 studies identified a pooled prevalence rate of meningococcal disease or carriage of 15.9% (95%CI: 4.45–27.4%) and the most frequent infecting organisms to be Serotype C (13.9%; 95%CI: −14.7 to 42.5; 4 studies) and A (11.5%; 95%CI: −2.13 to 25.2; 9 studies) among those at MGs or traveling. Age, gender, smoking history, and the vaccination status did not affect the infection risk. Conclusions: There is an increased prevalence of meningococcal disease and carriage, especially Serogroups A and C, associated with MGs and travel. New interventions and methodologies should be undertaken to control and prevent meningococcal disease or carriage transmission during such events. Full article

In the United States, adolescents and young adults between the ages of 16 and 23 have high rates of serogroup B meningococcal infections due to an elevated risk for those attending college. This review examines meningococcal vaccination requirements and recommendations for college students in the United States, with a focus on state-level mandates. National stakeholder resources, state legislatures, and official state Department of Health and Department of Education websites were analyzed for each state and Washington, DC. Overall, 26 states mandate MenACWY vaccination for college entry, whereas only 2 have specific requirements for MenB vaccination. Among the six states with the largest state university campus enrollments, half mandate MenACWY vaccination for college students, whereas none mandate MenB. By region, the Northeast had the highest percentage of states with a MenACWY requirement for college entry (77.8%) followed by the South (64.7%), Midwest (41.7%), and West (23.1%). Further research is needed to elucidate the relationship between state mandates and coverage to aid in optimizing meningococcal vaccination for college students. Full article

Children with hemato-oncological diseases represent a heterogeneous population at heightened risk for vaccine-preventable diseases. Their immunosuppressed state reduces vaccine efficacy and raises safety concerns regarding live attenuated vaccines due to the risk of viral reactivation. The immunological and clinical implications of the single conditions are significantly different; therefore, specific vaccination strategies are needed. Despite the availability of vaccine guidelines for immunocompromised patients, clinical practice remains highly variable. It is generally recommended to avoid vaccinations during chemotherapy, with some exceptions for influenza, pneumococcal, and, in some countries, hepatitis B vaccines. The timing of immune recovery after chemotherapy depends on the specific treatment and most guidelines recommend administering vaccines 3–6 months after treatment cessation. Concerning HSCT, the timing of immune recovery is affected by several factors such as the HSCT platform, graft-versus-host disease (GvHD), and infections. Inactivated vaccines are typically administered 3–6 months post-HSCT, while live attenuated vaccines are delayed for at least two years. In children with asplenia or hyposplenism, recommendations focus on immunization against encapsulated bacteria, with tailored schedules based on the patient’s age and underlying condition. This paper explores the biological factors influencing vaccination efficacy and safety in pediatric hematology and oncology patients. It also provides an updated overview of the available evidence and current vaccination guidelines. Finally, this paper highlights the main clinical and research areas for further improvement to provide tailored vaccination schedules for this vulnerable population. Full article

Background: Invasive meningococcal disease (IMD) can lead to severe and fatal outcomes. Vaccines against meningococcus (serogroups B, MenB; or ACWY, MenACWY) are recommended for patients at high risk of developing IMD. Our aim was to identify high-risk patients through a systematic search of medical codes and to evaluate vaccination coverage by high-risk group. Methods: An observational retrospective study was conducted in patients discharged at Reina Sofía University Hospital (Cordoba, Spain) from 1 January 2000, to 31 December 2023. Selection of high-risk patients was conducted through national administrative and clinical databases and vaccination coverage was determined through the Andalusian electronic vaccine database. Vaccine coverages of MenB and MenACWY were calculated within risk groups. Finally, bivariate analyses were conducted to assess the potential association between coverage, sex, and the year of admission. Results: A total of 2689 patients with 2710 high-risk conditions for IMD were identified from the databases searched. Of the 1755 requiring MenB vaccination, only 624 (35.6%) had received one dose and 558 (31.8%) two doses. Of the 2710 requiring MenACWY vaccination, only 784 (28.9%) had received one dose and 520 (19.2%) two doses. Patients with properdin-complement deficiencies showed the lowest vaccination rates (<10%). For the rest of the high-risk groups, vaccination coverages were significantly lower when the condition was diagnosed before the immunization guideline recommendations (p < 0.001). Conclusions: The identification of high-risk patients through databases using R-coded algorithms is both feasible and effective for identifying and catching-up patients for vaccination. The population at risk of IMD lacks adequate meningococcal vaccination coverage. Our methodology can serve to identify patients in other regions and for different vaccines. Full article

Background/Objective: Bacteriological culture has been a widely used method for the detection of meningococcus, but it has low sensitivity and a long turnaround time. Molecular detection targeting capsule transport A (ctrA) gene has been used, but over 16% of meningococcal carriage isolates lack ctrA, resulting in false-negative reports. The Cu-Zn superoxide dismutase gene (sodC) is specific to N. meningitidis, and is not found in other Neisseria species, making it a useful target for improved detection of non-groupable meningococci without intact ctrA. The primary objective of this study was to evaluate the performance compassion of two in-house PCR methods, sodC gene- and ctrA gene-based PCR assays, for detecting N. meningitidis in asymptomatic carriers. The secondary objective was to assess antimicrobial resistance profiling of N. meningitidis isolates. Methods: The performance of sodC gene-based PCR assay compared to ctrA gene-based PCR for detection of N. meningitidis was evaluated using clinical samples (pharyngeal swabs; n = 137) collected from suspected asymptomatic carriers and culture-confirmed meningococci isolates (n = 49). Additionally, the antimicrobial sensitivity of the 49 isolates against antimicrobial drugs was determined using a disk diffusion test. Result: Of 49 DNA samples from culture-positive N. meningitidis isolates, the sodC gene-based PCR accurately identified all 49, whereas the ctrA gene-based PCR identified only 33 out of 49. Of 137 pharyngeal swabs, the sodC gene-based assay detected N. meningitidis DNA in 105 (76.6%), while the ctrA-based assay detected N. meningitidis DNA in 64 (46.7%). Out of the 49 N. meningitidis isolates, 43 (87.8%) were resistant to amoxicillin, 42 (83.7%) to ampicillin, 32 (65.3%) to trimethoprim–sulfamethoxazole, 22 (44.9%) to ceftazidime, 18 (36.7%) to ceftriaxone, and 7 (15.2%) to meropenem. Additionally, the majority of the isolates, 36 (73.5%), were sensitive to cefepime, 31 (63.3%) to ceftriaxone and meropenem, and 26 (53.1%) to ceftazidime. Conclusions: The findings of this study highlight the necessity of adopting non-capsular sodC-based PCR to replace ctrA in resource-constrained laboratories to improve N. meningitidis detection, and underscore the importance of periodic antimicrobial resistance surveillance to inform and adapt treatment strategies. Full article

Public funding of vaccines may enhance vaccination rates, co-administration, and timeliness. The impacts of including the serogroup B meningococcus vaccine (MenB) into the national immunisation schedule on vaccination rates, co-administration rates, and timeliness were assessed using a population-based pre-funding (2022) and post-funding (2023) study design. MenB vaccination rates improved after funding and were in line with previously funded vaccines. Co-administration rates also increased significantly. Timely administration increased, protecting children at an early age. Public funding has a positive impact on vaccine accessibility and early protection. Consistent population characteristics highlight the role of funding. Full article

Background: Neisseria meningitidis (meningococcus) is a Gram-negative bacterium that colonises the nasopharynx of about 10% of the healthy human population. Under certain conditions, it spreads into the body, causing infections with high morbidity and mortality rates. Although the capsule is the key virulence factor, unencapsulated strains have proved to possess significant clinical implications as well. Meningococcal meningitis is a primarily human infection, with limited animal models that are dependent on a variety of parameters such as bacterial virulence and mouse strain. In this study, we aimed to develop a murine Neisseria meningitidis meningitis model to be used in the study of various antimicrobial compounds. Method: We used a capsule-deficient Neisseria meningitidis strain that was thoroughly analysed through various methods. The bacterial strain was incubated for 48 h in brain–heart infusion (BHI) broth before being concentrated and injected intracisternally to bypass the blood–brain barrier in CD-1 mice. This prolonged incubation time was a key factor in increasing the virulence of the bacterial strain. A total of three more differently prepared inoculums were tested to further solidify the importance of the protocol (a 24-h incubated inoculum, a diluted inoculum, and an inactivated inoculum). Antibiotic treatment groups were also established. The clinical parameters and number of deaths were recorded over a period of 5 days, and comatose mice with no chance of recovery were euthanised. Results: The bacterial strain was confirmed to have no capsule but was found to harbour a total of 56 genes coding virulence factors, and its antibiotic susceptibility was established. Meningitis was confirmed through positive tissue culture and histological evaluation, where specific lesions were observed, such as perivascular sheaths with inflammatory infiltrate. In the treatment groups, survival rates were significantly higher (up to 81.25% in one of the treatment groups compared to 18.75% in the control group). Conclusion: We managed to successfully develop a cost-efficient murine (using simple CD-1 mice instead of expensive transgenic mice) meningococcal meningitis model using an unencapsulated strain with a novel method of preparation. Full article

Neisseria meningitidis is commensal of the human pharynx and occasionally invades the host, causing the life-threatening illness invasive meningococcal disease. The meningococcus is a highly diverse and adaptable organism thanks to natural competence, a propensity for recombination, and a highly repetitive genome. These mechanisms together result in a high level of antigenic variation to invade diverse human hosts and evade their innate and adaptive immune responses. This review explores the ways in which this diversity contributes to the evolutionary history and population structure of the meningococcus, with a particular focus on microevolution. It examines studies on meningococcal microevolution in the context of within-host evolution and persistent carriage; microevolution in the context of meningococcal outbreaks and epidemics; and the potential of microevolution to contribute to antimicrobial resistance and vaccine escape. A persistent theme is the idea that the process of microevolution contributes to the development of new hyperinvasive meningococcal variants. As such, microevolution in this species has significant potential to drive future public health threats in the form of hypervirulent, antibiotic-resistant, vaccine-escape variants. The implications of this on current vaccination strategies are explored. Full article

Despite its effectiveness in preventing invasive meningococcal disease (IMD), pediatric uptake of recombinant meningococcal vaccination for serogroup B meningitis (MenB) is low in Italy. This study aimed to investigate knowledge, attitudes, and practice (KAP) about IMD and the vaccine uptake for MenB from July to December 2019, in a sample collected from a series of local Facebook discussion groups from the provinces of Parma and Reggio Emilia (North-Eastern Italy; 337,104 registered users). A self-administered anonymous web-based questionnaire was used to collect demographics, knowledge status, perceived risk for contracting meningitis, attitude towards the utility of meningococcal vaccine, and willingness to receive/perform MenB vaccine in their offspring. In total, 541 parents returned a fully completed questionnaire (response rate of 1.6% of potential recipients), with a mean age of 39.2 years ± 6.3 (78.1% females). Meningococcal infection was identified as severe or highly severe by most participants (88.9%), while it was recognized as being frequent/highly frequent in the general population by 18.6% of respondents. The overall knowledge status was unsatisfactory (57.6% ± 33.6 of correct answers to the knowledge test). Even though 63.4% of participants were somewhat favorable to MenB/MenC vaccines, offspring’s vaccination towards MenB was reported by only 38.7% of participants. In a binary logistic regression model, the male gender of respondents (adjusted odds ratio [aOR] 3.184, 95% confidence interval [95%CI] 1.772 to 5.721), living in a municipality >15,000 inhabitants (aOR 1.675, 95%CI 1.051 to 2.668), reporting a favorable attitude on meningococcus B vaccine (aOR 12.472, 95%CI 3.030 to 51.338), having been vaccinated against serogroup B (aOR 5.624, 95%CI 1.936 to 16.337) and/or serogroup C (aOR 2.652, 95%CI 1.442 to 4.872), and having previously vaccinated their offspring against serogroup C meningococcus (aOR 6.585, 95%CI 3.648 to 11.888) were characterized as positive effectors of offspring’s vaccination. On the contrary, having a higher risk perception on vaccines was identified as the only negative effector (aOR 0.429, 95%CI 0.241 to 0.765). Our results hint towards extensive knowledge gaps on IMD and preventive interventions in the general population, suggesting that a positive attitude towards vaccines and vaccinations could be identified as the main effector also for MenB acceptance. Interventions in the general population aimed at improving confidence, compliance, and acknowledgment of the collective responsibility, as well as preventing actual constraints and the sharing of false beliefs on infectious diseases and their preventive measures, could therefore increase vaccination acceptance in both targeted individuals and their offspring. Full article

Glycoconjugate vaccines have proven their worth in the protection and prevention of infectious diseases. The introduction of the Haemophilus influenzae type b vaccine is the prime example, followed by other glycoconjugate vaccines. Glycoconjugate vaccines consist of two components: the carrier protein and the carbohydrate antigen. Current carrier proteins are tetanus toxoid, diphtheria toxoid, CRM197, Haemophilus protein D and the outer membrane protein complex of serogroup B meningococcus. Carbohydrate antigens have been produced mainly by extraction and purification from the original host. However, current efforts show great advances in the development of synthetically produced oligosaccharides and bioconjugation. This review evaluates the advances of glycoconjugate vaccines in the last five years. We focus on developments regarding both new carriers and antigens. Innovative developments regarding carriers are outer membrane vesicles, glycoengineered proteins, new carrier proteins, virus-like particles, protein nanocages and peptides. With regard to conjugated antigens, we describe recent developments in the field of antimicrobial resistance (AMR) and ESKAPE pathogens. Full article

Neisseria gonorrhoeae (gonococcus) and Neisseria meningitidis (meningococcus) are important global pathogens which cause the sexually transmitted diseases gonorrhea and meningitis, respectively, as well as sepsis. We prepared a review according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA), with the aims of (a) evaluating the data on the MenB vaccination as protection against sexually transmitted infections by N. gonorrhoeae and (b) to briefly comment on the data of ongoing studies of new vaccines. We evaluated existing evidence on the effect of 4CMenB, a multi-component vaccine, on invasive diseases caused by different meningococcal serogroups and on gonorrhea. Non-B meningococcal serogroups showed that the 4CMenB vaccine could potentially offer some level of protection against non-B meningococcal serogroups and N. gonorrhoeae. The assessment of the potential protection conferred by 4CMenB is further challenged by the fact that further studies are still needed to fully understand natural immune responses against gonococcal infections. A further limitation could be the potential differences between the protection mechanisms against N. gonorrhoeae, which causes local infections, and the protection mechanisms against N. meningitidis, which causes systemic infections. Full article

High rates of vaccination coverage in childhood represent one of the most important cost-effective tools of primary prevention and have substantially reduced the incidence of and mortality from vaccine-preventable diseases globally. Vaccination coverage of young people has not been well estimated in Greece. Anonymous self-completed questionnaires and the participants’ Child Health Booklet were used to estimate complete vaccination coverage of mandatory vaccinations against vaccine-preventable diseases of undergraduate students at the University of West Attica during the academic year 2020–2021. Student’s t-tests were used to estimate mean values. Overall, 79% (95% CI: 78–81%) of study participants were fully vaccinated. This coverage was lower in males especially for vaccines that should be done during childhood (p = 0.045). High vaccination percentage (>90%) was observed for the meningococcus group A, C, W135, Y, measles-mumps-rubella, hepatitis B and meningitis C vaccine. Nevertheless, suboptimal coverage was assessed for the booster dose of tetanus, diphtheria, pertussis, for the human papillomavirus vaccine among girls, for the tuberculosis, for the meningococcus group B, for the pneumococcal, and for the seasonal influenza vaccines. In conclusion, the promotion of routine vaccination programs for young adults needs to be strengthened. An identification system for under-vaccinated students, an efficient reminder system and university campus vaccine program practices should be established, particularly among males. Full article

In 2017 in Italy, a number of vaccinations became mandatory or started to be recommended and offered free of charge. In this study, we aimed at assessing the coverage rates for those vaccinations in the pre-mandatory era among students at the School of Medicine of Padua University studying the degree course in medicine and surgery (future physicians) on the basis of the vaccination certificates presented during health surveillance. The vaccinations considered were those against pertussis, rubella, mumps, measles, varicella, Haemophilus influenzae type b (which became mandatory in 2017), pneumococcus, meningococcus C and meningococcus B (only suggested and offered for free since 2017). The study enrolled 4706 students of medicine and surgery. High vaccine uptake was observed, especially in younger students (born after 1990), with vaccines against pertussis, rubella, mumps and measles. Good completion for Haemophilus influenzae type b and meningococcus C was also observed. Very low coverage rates (all under 10%) for vaccination against varicella, pneumococcus and meningococcus B were observed. In conclusion, uptake for some non-mandatory vaccines was below the recommended threshold, although younger generations showed a higher uptake, possibly as a results of policy implemented at the national level. Our findings support the idea to consider health surveillance visits also as an additional opportunity to overcome confidence and convenience barriers and offer vaccine administration. Full article

Neisseria meningitidis causes a devastating invasive disease but is also a normal colonizer of the human nasopharynx. Due to the rapid progression of disease, the best tool to protect individuals against meningococcal infections is immunization. Clinical experience with polysaccharide conjugate vaccines has revealed that an ideal meningococcal vaccine must prevent both invasive disease and nasal colonization, which confers herd immunity. However, not all meningococcal vaccines are equal in their ability to prevent nasal colonization, for unknown reasons. Herein, we describe recent efforts to utilize humanized mouse models to understand the impact of different meningococcal vaccines on nasal colonization. These mice are susceptible to nasal colonization, and they become immune following live nasal infection or immunization with matched capsule-conjugate or protein-based vaccines, replicating findings from human work. We bring together insights regarding meningococcal colonization and immunity from clinical work with findings using humanized mouse models, providing new perspective into the different determinants of mucosal versus systemic immunity. Then, we use this as a framework to help focus future studies toward understanding key mechanistic aspects left unresolved, including the bacterial factors required for colonization and immune evasion, determinants of nasal mucosal protection, and characteristics of an ideal meningococcal vaccine. Full article

General practitioners (GPs) play a critical role in patient acceptance of vaccination. Vaccine hesitancy (VH) is a growing phenomenon in the general population but also affects GPs. Few data exist on VH among GPs. The objectives of this analysis of a population of GPs in the Belgian Wallonia-Brussels Federation (WBF) were to: (1) determine the prevalence and the features of VH, (2) identify the correlates, and (3) estimate the discrepancy in vaccination’s behaviors between the GPs’ children and the recommendations made to their patients. An online survey was carried out among the population of general practitioners practicing in the WBF between 7 January and 18 March 2020. A hierarchical cluster analysis was carried out based on various dimensions of vaccine hesitancy: perception of the risks and the usefulness of vaccines as well as vaccine recommendations for their patients. A total of 251 GPs answered the survey. The average percentage of moderate to high vaccine hesitancy was 50.6%. Three factors were independently associated with increased risk of vaccine hesitancy: an age <50 years old, having no children, and having no contact with selected vaccine-preventable disease (measles, complicated influenza, chronic hepatitis B (HBV), bacterial meningitis, or cervical cancer) in the past 5 years. VH was associated with controversies on vaccines’ safety. GPs who had vaccinated their children against six diseases (MMR, meningococcus C (MenC), HBV, and HPV) tended not to recommend the same vaccines to their patients. Among GPs with all children vaccinated against HBV, only 37.5% recommended catch-up HBV immunization to their patients. In this small cohort of GP, moderate to high VH was associated with controversies on vaccines’ safety and with specific personal characteristics (age <50, no children, and no recent experience with a serious VPD). As previously reported, GPs have different vaccine prescription attitude toward their patients and children. These findings should be confirmed in larger cohorts. Full article