Search Results (105)

Introduction: Despite the advances in its prevention, invasive meningococcal disease (IMD) remains a serious health problem worldwide due to its high morbidity and mortality, including in Romania, with 22% mortality rate. The objectives were to describe the trends of IMD cases admitted to a tertiary care hospital in Romania, over 24 years, and the case fatality rate (CFR) by age, year of admission, and Neisseria meningitidis serogroups. Materials and Methods: A retrospective study was conducted in IMD patients admitted to the National Institute for Infectious Diseases “Prof. Dr. Matei Bals”, Bucharest, Romania, between 2001 and 2024. Results: A total of 256 IMD patients were admitted, 171 under fourteen years, out of which 75 were infants. Most cases were reported before 2008. The case distribution showed 90 patients (35%) with meningitis, 84 (32%) with meningococcaemia, and 82 (32%) with an association of both. Serogroup B was the most frequently and steadily found (58 cases). The overall CFR was 12%. CFR was highest in infants younger than 6 months (19%) and meningococcaemia cases (29%). Conclusions: In our study, IDM had the highest frequency and CFR in infants and meningococcaemia cases. The trends showed a decline in cases after 2008. Serogroup B was the most prevalent and stable strain over 24 years. Full article

Background: During the COVID-19 pandemic, reductions in cases of bacterial diseases transmitted via the respiratory route were reported by the Invasive Respiratory Infection Surveillance Consortium. Here, we evaluate the epidemiology of invasive meningococcal disease (IMD) in Argentina, Brazil, Chile, and Colombia during and after the COVID-19 pandemic. Methods: The epidemiology of meningococcal disease was reviewed in selected South American countries through 2023 from publicly available national surveillance system databases. Results: The incidence of IMD decreased substantially in 2020 in Argentina, Brazil, Chile, and Colombia and was followed by a trend of increased disease. Similarly to observations in several European countries, the post-pandemic rebounds in cases of IMD in the four South American countries included in this analysis were mainly caused by serogroup B, that became one of the predominant serogroups causing IMD in all four countries. Conclusions: Enhanced surveillance of IMD, including genomic characterization of strains, is needed to inform public health policymakers and guide future vaccination strategies in the region. Full article

The increase in the incidence and antibiotic-resistant strains show a need for a broadly protective vaccine to prevent gonorrhea. OMVax has developed a combination vaccine based on native outer membrane vesicles (NOMVs) from two Neisseria meningitidis (Nm) and two Neisseria gonorrhoeae (Ng) strains. The strains had the acyl transferase LpxL1 knocked out to increase safety, and the reduction-modifiable protein was also knocked out in the Ng strains. Factor H binding protein (FHbp) mutants with reduced Factor H (FH) binding from Subfamilies A and B, respectively, were overexpressed in the Nm strains. The Ng strains individually expressed porin outer membrane protein B 1a (PorB.1a) or PorB.1b. Antibodies elicited by the Nm-Ng NOMV vaccine had SBA with a human complement against diverse Nm and Ng strains grown in the presence of Cytidine-5′-monophospho-N-acetylneuraminic acid (CMP-NANA), had no significant reduction in serum bactericidal activity (SBA) compared to the respective individual vaccines, inhibited the adhesion to human cervical and vaginal cells in five out of six Ng strains tested, and inhibited Nm and Ng colonization in a transgenic mouse model. In conclusion, the Nm-Ng NOMV vaccine has the potential to protect against disease and inhibit colonization by diverse Nm and Ng strains, which may be an advantage for controlling the disease through vaccination, particularly in the adolescent/young adult age group. Full article

Laboratory confirmation of invasive meningococcal disease (IMD) relies on detection of Neisseria meningitidis in a biological specimen. Clinical management guidelines for patients presenting with signs and/or symptoms of meningitis and encephalitis emphasize the need for appropriate specimen collection for laboratory testing. To explore the potential for IMD under-diagnosis, we reviewed medical records of patients admitted with signs and/or symptoms of meningitis or encephalitis at five hospitals in Louisville, Kentucky, in 2014 to 2023. Among 675 patients admitted with meningitis and/or encephalitis with cerebrospinal fluid (CSF) cultures who received antibiotics, 300 (44.4%) received antibiotics before CSF collection. Among 431 with blood cultures who received antibiotics, 133 (30.9%) received antibiotics before blood collection. Among 751 patients with CSF collected, 651 (86.7%) CSF specimens were tested using polymerase chain reaction (PCR) for N. meningitidis detection. No blood specimens were PCR-tested. These findings indicated that current standard-of-care practices may lead to IMD under-diagnosis. Since public health surveillance relies on IMD laboratory diagnosis, these findings highlight the potential for under-ascertained IMD by surveillance. Full article

Background: Meningococcal B (MenB) vaccination offers protection against invasive meningococcal disease and moderate cross-protection against gonorrhea. However, little is known about coverage and behavioral correlates among men who have sex with men (MSM) in China. This study assessed self-reported MenB vaccination uptake and its associations with sociodemographic and behavioral factors. Methods: We conducted a nationwide cross-sectional survey among 1022 MSM recruited via community-based organizations and online platforms. Vaccination status and recent sexual behaviors were self-reported. Logistic regression identified correlates of uptake, and latent class analysis (LCA) examined behavioral profiles. Results: Participants had a mean age of 29.6 years; most were unmarried (87.7%) and nearly 90% had a college degree or above. Overall, 21.7% reported receiving MenB vaccination. Uptake was positively associated with condomless anal intercourse (aOR = 1.57, 95% CI: 1.08–2.31), group sex (occasionally: aOR = 1.63, 95% CI: 1.01–2.64; frequently: aOR = 3.86, 95% CI: 1.85–8.04), and female partners in the past six months (aOR = 3.69, 95% CI: 2.25–6.10). MSM with multiple casual male partners were less likely to be vaccinated (aOR = 0.55, 95% CI: 0.32–0.93). LCA identified heterogeneous subgroups; notably, the “multi-partner and proactive” group, with high pre-exposure prophylaxis against HIV infection awareness and frequent STI testing, showed low uptake (13.4%). Conclusions: MenB vaccination coverage among MSM in China remained suboptimal. Uptake differed across behavioral subgroups, underscoring the need for stratified, context-specific strategies to inform future vaccine introduction. Full article

Background: Invasive meningococcal disease (IMD) is an uncommon but potentially life-threatening condition, resulting in life-long sequelae or death in up to 20% of cases. Most IMD cases are caused by Neisseria meningitidis serogroups (Men) A, B, C, W, X, and Y. The highest IMD incidence is among children < 5 years of age (YOA). We reviewed IMD epidemiology data and existing national immunization programs (NIP) in the Americas and identify unmet needs to decrease IMD burden in young children. Methods: Using national surveillance data and published literature from 2006 to 2024, we evaluated the IMD burden and national vaccination strategies for children < 5 YOA in the Americas, focusing on Canada, the United States, Brazil, Chile, Argentina. Results: The highest IMD incidence was among infants, followed by children 1–4 YOA, with MenB infections predominating in both age groups. Chile has both MenACWY (2014) and MenB (2023) infant vaccination in its NIP. Argentina and Brazil’s NIPs include MenACWY (2017) and MenC (2010) vaccinations for infants, respectively. In Canada, MenC (2002) vaccination is recommended at 1 YOA (replaced by MenACWY in 2024 in Manitoba); MenB vaccination is selectively recommended. In each country, the incidence of IMD caused by vaccine-preventable serogroups decreased following the introduction of the respective meningococcal vaccination in the NIP. Conclusions: Comprehensive meningococcal vaccination programs in the Americas have the potential to reduce the IMD burden in children < 5 YOA. National recommendations and NIPs could reduce IMD burden by offering equitable access to protection against IMD, aligning with the WHO roadmap to defeat meningitis by 2030. Full article

Background/Objectives: Meningococcal disease (MD) remains a significant public health concern worldwide. In Serbia, mandatory immunization against MD with the meningococcal polysaccharide vaccine (MenAC) for high-risk groups and international travelers was introduced in 2006. Since 2017, the polysaccharide vaccine has been replaced with the quadrivalent meningococcal conjugate vaccine (MenACWY). The aim of this study was to analyze long-term trends in incidence, age-specific patterns, seasonality, and lethality of invasive meningococcal disease (IMD) in the Autonomous Province of Vojvodina (AP Vojvodina), Serbia, over a 28-year period. Methods: A descriptive study analyzed all reported cases of IMD in AP Vojvodina, from 1997 to 2024. Data were obtained from the regional communicable disease surveillance system, based on mandatory hospital reporting and case classification according to national and WHO guidelines. Temporal, demographic, and clinical characteristics, along with disease outcomes, were analyzed. Results: From 1997 to 2024, 175 IMD cases were reported in AP Vojvodina. The annual incidence peaked in 1997 (1.24/100,000), with smaller surges in 2003 and 2005. Since 2006, coinciding with the introduction of immunization against MD, a sustained decline has been observed, with incidence rarely exceeding 0.30/100,000. A slight resurgence occurred in 2023–2024, with 13 cases reported. From 1997 to 2024, IMD in AP Vojvodina exhibited a clear seasonal pattern, with most cases occurring in winter and early spring, peaking in January (17%), March (12%), and February (11%), and the fewest cases occuring in the summer months. Throughout the study period, the highest IMD incidence rates were consistently observed among infants <1 year of age and children aged 1–4 years, with peaks of up to 22.9/100,000 and 16.0/100,000, respectively. Incidence was much lower in older age groups, especially adults. After a 2006 peak, rates declined across all ages, with a slight resurgence in 2023–2024 among children and adolescents. Children aged 1–4 years made up the largest share of IMD cases, peaking in January–March (45.1%). Half of the infant cases were recorded in October–November, while cases in older children, adolescents, and adults were fewer and showed varied monthly patterns, with small peaks in winter and early spring. During the 28-year study period, the highest IMD mortality rate was observed among infants <1 year of age (0.59 per 100,000 population), followed by children aged 1–4 years (0.32 per 100,000). Mortality rates declined progressively with increasing age, with the lowest rate recorded among individuals aged ≥40 years (0.01 per 100,000). Of the 175 IMD cases reported in AP Vojvodina (1997–2024), 21 were fatal (case fatality rate [CFR] = 12.0%). The CFR of IMD varied across age groups. The highest CFR was observed among individuals aged ≥40 years (21.4%), followed by the 5–9 years (17.4%) and <1 year (16.7%) age groups. None of the patients had been vaccinated against MD. Fatal outcomes were more common in children aged 1–4 years and among rural residents, though differences were not statistically significant (p > 0.05). Most deaths (57.1%) occurred in the first quarter of the year. A strong association was found between clinical form and outcome, with meningococcal sepsis being significantly more frequently associated with fatality than meningitis (p = 0.0002). Deaths were sporadic over time, with most occurring within 1–2 days of notification. All confirmed fatal cases were due to serogroup B. Conclusions: MD remains a rare yet serious public health threat in AP Vojvodina. Mortality rates indicate that the public health impact of this disease is greatest among the youngest age groups; however, the risk of death, i.e., disease severity, does not appear to be age dependent. The recent rise in cases, high fatality among sepsis patients, and absence of prior vaccination among all IMD cases highlight the need for enhanced surveillance, physician education, and consideration of introducing both MenACWY and MenB vaccines for high-risk groups. Full article

Meningococcal meningitis is a deadly acute bacterial infection caused by the Neisseria meningitidis bacterium that affects the membrane covering the brain and spinal cord. The World Health Organization launched the “Defeating bacterial meningitis by 2030” initiative in 2018, which relies on recent discoveries of cheap and effective vaccines. Here, we consider one important factor—human behavior—which is often neglected by immunization campaigns. We constructed a game-theoretic model of meningitis in the meningitis belt, where individuals make selfish rational decisions whether to vaccinate based on the assumed costs and the vaccination decisions of the entire population. We identified conditions when individuals should vaccinate, and we found the optimal (equilibrium) population vaccination rate. We conclude that voluntary compliance significantly reduces the endemic levels of meningitis if the cost of vaccination relative to the cost of the disease is sufficiently low, but it does not eliminate the disease. We also performed uncertainty and sensitivity analysis on our model. Full article

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

Background: Neisseria meningitidis B is one of the main causative pathogens of meningitis and other forms of severe meningococcal disease. In the past decade, meningococcal B vaccines have been developed to address this infection and its sequelae. Objective: This article aims to present an example of how the EU regulatory framework allowed the early authorisation of two life-saving vaccines initially based on immunogenicity surrogates of clinical evidence. This was subsequently followed by post-marketing surveillance providing real-world evidence to support their safety profile and impact on the paediatric population in the EU. Methods: We review the evidence supporting the initial regulatory approval of the vaccines, the confirmatory data demonstrating vaccine effectiveness post-authorisation, and the real-world impact of these vaccines on the paediatric population. Results: Two vaccines were approved in the EU for active immunisation to prevent IMD caused by MenB (4CMenB in 2013 and MenB-fHBP in 2017). Both marketing authorisations were based on immunogenicity data (efficacy studies were not feasible due to the rarity of the disease) and safety data generated from pre-authorisation studies. Additional pharmacovigilance activities to further investigate the safety profile and effectiveness studies were requested to be conducted after approval. Both the effectiveness and safety profile of the vaccines were confirmed by these data. Conclusions: This paper illustrates that the EU medicines regulatory framework and safety monitoring system are robust. By supplementing the initial evidence with post-authorisation studies, further effectiveness and safety data enabled regulators to confirm the positive benefit–risk of the vaccines without delaying their access to the people who need them. Full article

Background/Objectives: In France, non-pharmaceutical interventions (NPIs) implemented to control COVID-19 led to a significant decline in invasive meningococcal disease (IMD) cases. However, a rebound in cases, particularly for serogroups W and Y, was observed after the gradual lifting of NPIs, raising questions about an “immunity gap” due to reduced circulation of the bacteria. During the study period, vaccination against MenC was mandatory from 2018, and vaccination against MenB has been recommended since 2022. Methods: We conducted a retrospective seroepidemiological study using 166 normal sera collected between 2016 and 2024. Anti-Neisseria meningitidis IgG levels were quantified by ELISA using purified capsular polysaccharides for serogroups B, C, W, Y, and X. Samples were categorized into three periods: pre-NPIs (n = 72), during NPIs (n = 33), and post-NPIs (n = 61). Statistical comparisons were performed using Kruskal–Wallis tests for non-parametric data. Results: Our results show a significant decline in anti-serogroup B IgG antibody levels after the lifting of NPIs (p < 0.0001) in line with reduced circulation. Anti-serogroup C IgG antibody levels increased incrementally (p = 0.0003), particularly in those aged 1–4 years, likely reflecting a catch-up in anti-meningococcal C vaccination coverage. Anti-serogroup W IgG antibody levels remained stable, suggesting sustained circulation, but shifted to young children in the post-NPI period, potentially due to a genotypic shift. Anti-serogroup Y IgG antibody levels transiently increased significantly (p < 0.0001) during the NPI period but then decreased back after their lifting. Anti-serogroup X IgG antibody levels remained stable, consistent with its low prevalence and the absence of targeted vaccination. Full article

Background: The Spanish Interterritorial Council of the National Health System (a central government body) currently recommends vaccination against meningococcal serogroup C (MenC) at 4 and 12 months of age for prevention of invasive meningococcal disease (IMD). The Advisory Committee on Vaccines of the Spanish Association of Pediatrics (a professional medical association) and numerous Spanish regional bodies instead recommend quadrivalent vaccination against serogroups A, C, W, and Y (MenACWY) at 4 and 12 months of age. The central government and Spanish Association of Pediatrics also recommend MenACWY vaccination at 12 years of age. This study assessed the potential public health effects of replacing the MenC vaccination schedule with different MenACWY vaccination schedules in infants. Methods: Here, a static multi-cohort population model was used to evaluate potential effects on public health of IMD due to meningococcal serogroups C/W/Y, comparing MenC infant vaccination (reference strategy) against four different strategies including quadrivalent tetanus toxoid conjugate vaccine (MenACWY-TT; Nimenrix^®, Pfizer Europe MA EEIG, Brussels, Belgium) infant vaccination; all strategies included MenACWY-TT vaccination at 12 years of age. Results: The most effective strategy for infant vaccination was MenACWY-TT at 2, 4, and 12 months, preventing an estimated additional 103 IMD cases, 17 deaths, and 41 cases with long-term sequelae (LTS) versus the reference strategy in the base-case IMD incidence scenario. When strategies included a two-dose infant schedule, the earlier the infant MenACWY-TT vaccine was administered, the more additional cases, deaths, and cases with LTS were prevented (base-case and high-incidence scenarios). Conclusions: This analysis supports implementation of MenACWY-TT as a replacement for MenC vaccination. Full article

Background: Neisseria meningitidis (N. meningitidis) is a leading cause of acute meningitis and is classified into 13 serogroups, six of which are predominantly associated with invasive meningococcal disease. This study aimed to investigate the genotype, subgenotype, and antigenic profiles of N. meningitidis serogroup B strains isolated in Vietnam. Methods: Genotyping was performed on 106 N. meningitidis strains isolated from clinical samples from Vietnamese patients and nasopharyngeal swabs of healthy adolescents between 2019 and 2024. The genetic profiles, including the porA, porB, fetA, fHbp, abcZ, adk, aroE, fumC, gdh, pdhC, and pgm genes, were analyzed using Sanger sequencing and bioinformatic methods. Results: We found that 84.9% of the strains carried VR3 families 36 or 35-1, with VR1, VR2, and VR3 families 22-25, 14, and 36 being the most prevalent. Among the 106 serogroup B isolates, 20 variants of the porB allele 3 were identified, with porB 3-1212 being the most frequent (30.2%). Dominant PorB variable loops included L1.6, L4.5, L5.7, L6.6, and L7.13. fHbp variant group 2 was predominant (104/106 strains), and 12 FetA allele variants were identified, with F1-7 being the most common (47.2%). Three clonal complexes were identified, and clonal complex ST-32 was the most predominant. Fifty-five strains (51.9%) belonged to sequence types that have not yet been assigned to any clonal complexes, and 15 strains (14.1%) with allelic profiles were not assigned to STs. The 3-253 and 3-1212 alleles of porB, the F1-7 variant of FetA, the ST-44 and ST-1576 sequence types, and the ST-41/44 complex were observed more frequently in patients compared to asymptomatic carriers, suggesting their association with more virulence. Conclusions: This study showed a high genetic and antigenic diversity of N. meningitidis serogroup B isolates in Vietnam, with VR3 family 36 most common and porB 3-1212 as the predominant allele. fHbp variant group 2 and FetA allele F1-7 were most frequent. ST-32 was the dominant clonal complex, though many strains remained unassigned, highlighting the need for ongoing molecular surveillance. Full article

Aim: This study aimed to evaluate the knowledge and attitudes of family physicians and family health personnel who are responsible for childhood vaccination services in primary care regarding meningococcal, rotavirus, and human papillomavirus vaccines. Methods: This cross-sectional study was conducted between October 2021 and January 2022. A total of 700 healthcare professionals from all geographical regions in Turkey were included in the study. The participants filled out an online questionnaire consisting of 39 questions created with Google Forms. Results: Of the participants, 340 (48.6%) are family physicians, and 360 (51.4%) are family health personnel. Most participants are from the Marmara region, Turkey’s most densely populated region. The most recommended vaccine among the participants was rotavirus (84.3%), while the least recommended vaccine was human papilloma virus (47.6%). The number of family physicians recommending meningococcal and human papilloma virus vaccines was significantly higher than that of family health personnel (p < 0.001). Furthermore, there was a statistically significant correlation between seeing a patient with these viruses in one’s professional life or considering the severity of these three diseases to be severe and recommending these vaccines (p < 0.001 for both). However, lack of knowledge about vaccines and doses, the high cost of vaccines, and concerns about side effects were among the reasons for not recommending vaccines. Conclusions: Healthcare professionals involved in childhood immunization should be trained to increase their knowledge and awareness on this issue. The training plan and curriculum should take into account the issues raised in our research, such as age, occupation, region of residence, and professional experience. In general, knowledge about the efficacy and safety of vaccines will help healthcare professionals develop their confidence in vaccines and willingness to recommend childhood vaccines to others. Full article

Invasive meningococcal disease (IMD) remains a major public health challenge due to its rapid progression, which may lead to severe sequelae or death in children and adolescents. Published data on IMD sequelae are limited in Greece and many EU countries. In the present study, patients under 16 years of age with IMD were retrospectively identified from the files of the Hellenic National Meningitis Reference Laboratory (HNML) from 2010–2020, and their medical records were tracked from the corresponding hospitals. Demographic, clinical, and microbiological data were recorded for each case. A total of 161 patients younger than 16 years of age admitted to nine hospitals across the country were identified. Of those, 91 (56.5%) records were found. The patients’ median age was 36 months (range 22 days to 16 years old); 37.4% presented with meningitis, 36.2% with both septicemia and meningitis, and 26.4% only with septicemia. The mortality rate was 5.5% and was significantly associated with septicemia, abnormal platelet count at presentation, ICU admission, and coagulation disorders, while sequelae were detected in 16.9% of patients upon discharge. Neisseria meningitidis serogroup B (MenB) was the most predominant (77%); of these, 269 cc was identified (36.8%). This is the first study on unfavorable sequelae and mortality due to IMD performed in Greece. Full article