Meningococcal Research Articles

An Assessment of a New Rapid Multiplex PCR Assay for the Diagnosis of Meningoencephalitis.

The rapid and broad microbiological diagnosis of meningoencephalitis (ME) has been possible thanks to the development of multiplex PCR tests applied to cerebrospinal fluid (CSF). We aimed to assess a new multiplex PCR panel (the QIAstat-Dx ME panel), which we compared to conventional diagnostic tools and the Biofire FilmArray ME Panel. The pathogens analyzed using both methods were Escherichia coli K1, Haemophilus influenzae, Listeria monocytogenes, Neisseria meningitidis, Streptococcus agalactiae, Streptococcus pneumoniae, Enterovirus, herpes simplex virus 1-2, human herpesvirus 6, human parechovirus, varicella zoster virus, and Cryptococcus neoformans/gattii. We used sensitivity, specificity, PPV, NPV, and kappa correlation index parameters to achieve our objective. Fifty CSF samples from patients with suspected ME were included. When conventional methods were used, 28 CSF samples (56%) were positive. The sensitivity and specificity for QIAstat-Dx/ME were 96.43% (CI95%, 79.8-99.8) and 95.24% (75.2-99.7), respectively, whereas the PPV and NPV were 96.43% (79.8-99.8) and 95.24% (75.1-99.7), respectively. The kappa value was 91.67%. Conclusions: A high correlation of the QIAstat-Dx ME panel with reference methods was shown. QIAstat-Dx ME is a rapid-PCR technique to be applied in patients with suspected ME with a high accuracy.

Children with perinatally acquired HIV exhibit distinct immune responses to 4CMenB vaccine.

Children with perinatally acquired HIV (PHIV) have special vaccination needs, as they make suboptimal immune responses. Here, we evaluated safety and immunogenicity of 2 doses of 4-component group B meningococcal vaccine in antiretroviral therapy-treated children with PHIV and healthy controls (HCs). Assessments included the standard human serum bactericidal antibody (hSBA) assay and measurement of IgG titers against capsular group B Neisseria meningitidis antigens (fHbp, NHBA, NadA). The B cell compartment and vaccine-induced antigen-specific (fHbp+) B cells were investigated by flow cytometry, and gene expression was investigated by multiplexed real-time PCR. A good safety and immunogenicity profile was shown in both groups; however, PHIV demonstrated a reduced immunogenicity compared with HCs. Additionally, PHIV showed a reduced frequency of fHbp+ and an altered B cell subset distribution, with higher fHbp+ frequency in activated memory and tissue-like memory B cells. Gene expression analyses on these cells revealed distinct mechanisms between PHIV and HC seroconverters. Overall, these data suggest that PHIV presents a diverse immune signature following vaccination. The impact of such perturbation on long-term maintenance of vaccine-induced immunity should be further evaluated in vulnerable populations, such as people with PHIV.

Prevention and treatment of infection in patients with an absent or hypofunctional spleen: A British Society for Haematology guideline.

Guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen were published by the British Committee for Standards in Haematology in 1996 and updated in 2002 and 2011. With advances in vaccinations and changes in patterns of infection, the guidelines required updating. Key aspects included in this guideline are the identification of patients at risk of infection, patient education and information and immunisation schedules. This guideline does not address the non-infective complications of splenectomy or functional hyposplenism (FH). This replaces previous guidelines and significantly revises the recommendations related to immunisation. Patients at risk include those who have undergone surgical removal of the spleen, including partial splenectomy and splenic embolisation, and those with medical conditions that predispose to FH. Immunisations should include those against Streptococcus pneumoniae (pneumococcus), Neisseria meningitidis (meningococcus) and influenza. Haemophilus influenzae type b (Hib) is part of the infant immunisation schedule and is no longer required for older hyposplenic patients. Treatment of suspected or proven infections should be based on local protocols and consider relevant anti-microbial resistance patterns. The education of patients and their medical practitioners is essential, particularly in relation to the risk of serious infection and its prevention. Further research is required to establish the effectiveness of vaccinations in hyposplenic patients; infective episodes should be regularly audited. There is no single group ideally placed to conduct audits into complications arising from hyposplenism, highlighting a need for a national registry, as has proved very successful in Australia or alternatively, the establishment of appropriate multidisciplinary networks.

Investigation and response to an outbreak of Neisseria meningitidis serogroup Y ST-1466 urogenital infections, Australia.

In 2023, an increased number of urogenital and anorectal infections with Neisseria meningitis serogroup Y (MenY) were reported in New South Wales (NSW). Whole genome sequencing (WGS) found a common sequence type (ST-1466), with limited sequence diversity. Confirmed outbreak cases were NSW residents with a N. meningitidis isolate matching the cluster sequence type; probable cases were NSW residents with MenY isolated from a urogenital or anorectal site from 1 July 2023 without WGS testing. Of the 41 cases, most were men (n = 27), of whom six reported recent contact with a female sex worker. Five cases were men who have sex with men and two were female sex workers. Laboratory alerts regarding the outbreak were sent to all Australian jurisdictions through the laboratories in the National Neisseria Network. Two additional states identified urogenital MenY ST-1466 infections detected in late 2023. Genomic analysis showed all MenY ST-1466 sequences were interspersed, suggestive of an Australia-wide outbreak. The incidence of these infections remains unknown, due to varied testing and reporting practices both within and across jurisdictions. Isolates causing invasive meningococcal disease (IMD) in Australia are typed, and there has been no MenY ST-1466 IMD recorded in Australia to end of March 2024. Concerns remain regarding the risk of IMD, given the similarity of these sequences with a MenY ST-1466 IMD strain causing a concurrent outbreak in the United States of America.

Safety and Efficacy of Pegcetacoplan in Adult Patients with Paroxysmal Nocturnal Hemoglobinuria over 48Weeks: 307 Open-Label Extension Study.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, life-threatening disease characterized by complement-mediated hemolysis and thrombosis. Pegcetacoplan, the first targeted complement component3 (C3) PNH therapy, was safe and efficacious in treatment-naive and pre-treated patients with PNH in five clinical trials. The 307 open-label extension (OLE) study (NCT03531255) is a non-randomized, multicenter extension study of long-term safety and efficacy of pegcetacoplan in adult patients with PNH who completed a pegcetacoplan parent study. All patients received pegcetacoplan. Outcomes at the 48-week data cutoff (week48 of 307-OLE or August 27, 2021, whichever was earlier) are reported. Hemoglobin concentrations, Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scores, and transfusion avoidance were measured. Hemoglobin > 12g/dL and sex-specific hemoglobin normalization (i.e., male, ≥ 13.6g/dL; female, ≥ 12g/dL) were assessed as percentage of patients with data available and no transfusions 60days before data cutoff. Treatment-emergent adverse events, including hemolysis, were reported. Data from 137 patients with at least one pegcetacoplan dose at data cutoff were analyzed. Mean (standard deviation [SD]) hemoglobin increased from 8.9 (1.22) g/dL at parent study baseline to 11.6 (2.17) g/dL at 307-OLE entry and 11.6 (1.94) g/dL at data cutoff. At parent study baseline, mean (SD) FACIT-Fatigue score of 34.1 (11.08) was below the general population norm of 43.6; scores improved to 42.8 (8.79) at 307-OLE entry and 42.4 (9.84) at data cutoff. In evaluable patients, hemoglobin > 12g/dL occurred in 40.2% (43 of 107) and sex-specific hemoglobin normalization occurred in 31.8% (34 of 107) at data cutoff. Transfusion was not required for 114 of 137 patients (83.2%). Hemolysis was reported in 23 patients (16.8%). No thrombotic events or meningococcal infections occurred. Pegcetacoplan sustained long-term improvements in hemoglobin concentrations, fatigue reduction, and transfusion burden. Long-term safety findings corroborate the favorable profile established for pegcetacoplan. ClinicalTrials.gov identifier, NCT03531255.

Multicentre double-blind randomised placebo-controlled trial evaluating the efficacy of the meningococcal B vaccine, 4CMenB (Bexsero), against Neisseria gonorrhoeae infection in men who have sex with men: the GoGoVax study protocol

IntroductionGonorrhoea, the sexually transmissible infection caused by Neisseria gonorrhoeae, has a substantial impact on sexual and reproductive health globally with an estimated 82 million new infections each year worldwide. N....

Concurrent Outbreaks of Hepatitis A, Invasive Meningococcal Disease, and Mpox, Florida, USA, 2021-2022.

In 2022, concurrent outbreaks of hepatitis A, invasive meningococcal disease (IMD), and mpox were identified in Florida, USA, primarily among men who have sex with men. The hepatitis A outbreak (153 cases) was associated with hepatitis A virus genotype IA. The IMD outbreak (44 cases) was associated with Neisseria meningitidis serogroup C, sequence type 11, clonal complex 11. The mpox outbreak in Florida (2,845 cases) was part of a global epidemic. The hepatitis A and IMD outbreaks were concentrated in Central Florida and peaked during March--June, whereas mpox cases were more heavily concentrated in South Florida and had peak incidence in August. HIV infection was more common (52%) among mpox cases than among hepatitis A (21%) or IMD (34%) cases. Where feasible, vaccination against hepatitis A, meningococcal disease, and mpox should be encouraged among at-risk groups and offered along with program services that target those groups.

Identifying the main determinants that have an impact on the level of vaccination among children

Background. Thanks to vaccinations, many infections, including whooping cough, diphtheria, tetanus, poliomyelitis, measles, mumps, rubella, hepatitis B, hemophilic infection, pneumococcal infection, meningococcal infection, rotavirus infection, chicken pox, hepatitis A, papillomavirus infection, etc., can be prevented. According to the WHO research, it was established that if the level of vaccination coverage of the country's population drops by several percents, it creates favorable conditions for the spread of infectious diseases, that the lower the collective immunity, the higher the probability of outbreaks and epidemics. The Aim. Тo study and analyze the impact of risk factors on reducing the level of vaccine prophylaxis in the childhood population. Materials and Methods. This study was conducted using the questionnaire method, for which a questionnaire was developed. Group 1 consisted of 280 children who received a vaccination and group 2 consisted of 180 children who were not vaccinated. The parents of these children were interviewed using the author's questionnaire and gave their consent to use the medical data of the children for scientific research. Non-parametric statistical analysis for two independent sample populations was used to compare median values Mann-Whitney test. Fisher's test was used to compare proportions. Results. During the study, it was found that the most frequent reasons for parents' refusal to vaccinate their children were: religious views of family members 2.4 times increase the risk of non-vaccination in children; in single-parent families where the parents are divorced, children did not receive any vaccination 2.6 times more than in full-parent families; unfinished average of 35.7 times and lack of education 24.1 times increase the impact on the lack of vaccination in children. Conclusions. We identified the following risk factors that influence the vaccination rate, namely: demographic, socio-economic, biological and socio-psychological. Keywords: vaccine prevention, statistics, infectious diseases, risk factors.

An isothermal CRISPR- based lateral flow assay for detection of Neisseria meningitidis

BackgroundNeisseria meningitidis can cause life-threatening meningococcal meningitis and meningococcemia. Old standard microbiological results from CSF/blood cultures are time consuming. This study aimed to combine the sensitivity of loop-mediated isothermal nucleic acid amplification (LAMP) with the specificity of CRISPR/Cas12a cleavage to demonstrate a reliable diagnostic assay for rapid detection of N. meningitidis.MethodsA total of n = 139 samples were collected from patients with suspected meningococcal disease and were used for evaluation. The extracted DNA was subjected to qualitative real-time PCR, targeting capsular transporter gene (ctrA) of N. meningitidis. LAMP-specific primer pairs, also targeting the ctrA, were designed and the LAMP products were subjected to CRISPR/Cas12 cleavage reaction. the readout was on a lateral flow strip. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of LAMP-CRISPR/Cas was compared with real-time PCR assays. The limit of detection (LOD) was established with serial dilutions of the target N. meningitidis DNA and calculated by Probit regression analysis.ResultsSix LAMP assay-specific primers were developed targeting the ctrA gene of N. meningitidis, which is conserved in all meningococcal serogroups. The LAMP primers did not amplify DNA from other bacterial DNA tested, showing 100% specificity. The use of 0.4 M betaine increased the sensitivity and stability of the reaction. LAMP-CRISPR/Cas detected meningococcal serogroups (B, C, W). The assay showed no cross-reactivity and was specific for N. meningitidis. The LOD was 74 (95% CI: 47–311) N. meningitidis copies. The LAMP-CRISPR/Cas performed well compared to the gold standard. In the 139 samples from suspected patients, the sensitivity and specificity of the test were 91% and 99% respectively.ConclusionThis developed and optimized method can complement for the available gold standard for the timely diagnosis of meningococcal meningitis and meningococcemia.

Risk of Invasive Meningococcal Disease in Preterm Infants.

Invasive meningococcal disease (IMD) is most common in the first year of life. We hypothesized that preterm infants may have a higher risk of IMD and more severe disease than term infants. We compared the incidence, demographics, clinical presentation, and outcomes of IMD in preterm compared with term infants during the first 5 years after implementation of a national meningococcal group B vaccine (4CMenB) for infants in England. The UK Health Security Agency conducts enhanced national IMD surveillance with detailed follow-up of all confirmed cases in England. Infants aged <1 year (uncorrected for gestational age) with IMD confirmed between 1 September 2015 and 31 August 2020 were included. There were 393 infant IMD cases (incidence, 12.4/100 000 live births). Among 363 (92.4%) of the infants with known gestational age, the IMD incidence was higher in preterm (<37 weeks' gestation) than in term infants (18.3/100 000 vs 10.9/100 000; incidence rate ratio [IRR], 1.68 [95% confidence interval, 1.23-2.29]; P = .001). The IMD incidence was highest in those born at <32 weeks' gestation (32.9/100 000; incidence rate ratio for <32 weeks' gestation vs term, 3.01 [95% confidence interval, 1.73-5.24]; P ≤ .001). There were no differences in demographics, clinical presentation, rate of intensive care admission, or case-fatality rate, but preterm infants were more likely than term infants to have ≥1 reported sequela (14 of 39 [35.9%] vs 51 of 268 [19.0%]; P = .02). Preterm infants had a higher incidence of IMD than term infants and the IMD incidence was highest in infants born at <32 weeks' gestation. Preterm infants also had a higher risk of IMD sequelae.

THE DIFFERENTIAL EXTRACTION METHOD OF NEISSERIA MENINGITIDIS AND NON-PATHOGENIC SPECIES FOR PROTEIN PROFILING BY SDS-PAGE

Invasive meningococcal disease (IMD) is an acute, severe, and potentially fatal infection caused by Neisseria meningitidis and is a global public health burden. Given the high fatality rate linked to acute bacterial meningitis, it is imperative to initiate treatment and diagnosis concurrently in most cases. While a culture demonstrating the growth of N. meningitidis from blood or cerebrospinal fluid (CSF) remains the gold standard, however, its sensitivity diminishes following antibiotic administration. Therefore, in this study, differentially extracted whole cell protein (WCP), surface depleted whole cell protein (sdWCP), and cell surface protein (CSP) profiles were analysed by using SDS-PAGE to characterise and classify pathogenic N. meningitidis and non-pathogenic species. This study provides clear evidence that SDS-PAGE yields distinct protein patterns across Men A, B, C, and Y, clinical isolates 1 and 2, N. sicca, N. cinerea, and M. catarrhalis. It effectively demonstrates that SDS-PAGE protein profiling can serve as a reliable method for characterising and separating bacterial proteins at both the species and strain levels. Despite the availability of more advanced technologies, SDS-PAGE remains a valuable tool, particularly in settings where advanced equipment and knowledgeable personnel are lacking. Our approach employs various extraction techniques, has successfully defined and characterised N. meningitidis, non-pathogenic Neisseria species, and M. catarrhalis.

Immunogenicity and protective capacity of a CpG ODN adjuvanted alum adsorbed bivalent meningococcal outer membrane vesicle vaccine.

Invasive meningococcal disease (IMD) is caused by Neisseria meningitidis, with the main serogroups responsible for the disease being A, B, C, W, X, and Y. To date, several vaccines targeting N. meningitidis have been developed albeit with a short-lived protection. Given that MenW and MenB are the most common causes of IMD in Europe, Turkey, and the Middle East, we aimed to develop an outer membrane vesicle (OMV) based bivalent vaccine as the heterologous antigen source. Herein, we compared the immunogenicity, and breadth of serum bactericidal activity (SBA) assay-based protective coverage of OMV vaccine to the X serotype with existing commercial meningococcal conjugate and polysaccharide (PS) vaccines in a murine model. BALB/c mice were immunized with preclinical batches of the W + B OMV vaccine, either adjuvanted with Alum, CpG ODN, or their combinations, and compared with a MenACYW conjugate vaccine (NimenrixTM, Pfizer), and a MenB OMV-based vaccine (Bexsero®, GSK), The immune responses were assessed through enzyme-linked immunosorbent assay (ELISA) and SBA assay. Antibody responses and SBA titers were significantly higher in the W + B OMV vaccine when adjuvanted with Alum or CpG ODN, as compared to the control groups. Moreover, the SBA titers were not only significantly higher than those achieved with available conjugated ACYW vaccines but also on par with the 4CMenB vaccines. In conclusion, the W + B OMV vaccine demonstrated the capacity to elicit robust antibody responses, surpassing or matching the levels induced by licensed meningococcal vaccines. Consequently, the W + B OMV vaccine could potentially serve as a viable alternative or supplement to existing meningococcal vaccines.

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

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. 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. 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. 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. This study was funded by the Meningitis Research Foundation, Pfizer and the NIHR Programme Grants for Applied Research.

Impact of Protein Nanoparticle Shape on the Immunogenicity of Antimicrobial Glycoconjugate Vaccines.

Protein self-assembling nanoparticles (NPs) can be used as carriers for antigen delivery to increase vaccine immunogenicity. NPs mimic the majority of invading pathogens, inducing a robust adaptive immune response and long-lasting protective immunity. In this context, we investigated the potential of NPs of different sizes and shapes-ring-, rod-like, and spherical particles-as carriers for bacterial oligosaccharides by evaluating in murine models the role of these parameters on the immune response. Oligosaccharides from Neisseria meningitidis type W capsular polysaccharide were conjugated to ring-shape or nanotubes of engineered Pseudomonas aeruginosa Hemolysin-corregulated protein 1 (Hcp1cc) and to spherical Helicobacter pylori ferritin. Glycoconjugated NPs were characterized using advanced technologies such as High-Performance Liquid Chromatography (HPLC), Asymmetric Flow-Field Flow fractionation (AF4), and Transmission electron microscopy (TEM) to verify their correct assembly, dimensions, and glycosylation degrees. Our results showed that spherical ferritin was able to induce the highest immune response in mice against the saccharide antigen compared to the other glycoconjugate NPs, with increased bactericidal activity compared to benchmark MenW-CRM197. We conclude that shape is a key attribute over size to be considered for glycoconjugate vaccine development.

Development and Validation of Multiplex Assays for Mouse and Human IgG and IgA to Neisseria gonorrhoeae Antigens.

There is an urgent need for vaccines against Neisseria gonorrhoeae, the causative agent of gonorrhea. Vaccination with an outer membrane vesicle-based Neisseria meningitidis vaccine provides some protection from N. gonorrhoeae; however, the mechanisms underlying this cross-protection are unknown. To address this need, we developed multiplexed bead-based assays for the relative quantification of human and mouse IgG and IgA against N gonorrhoeae antigens. The assays were evaluated for analyte independence, dilutional linearity, specificity, sensitivity, intra- and interassay variability, and robustness to sample storage conditions. The assay was then used to test samples from mice and humans immunized with an N meningitidis outer membrane vesicle vaccine.

Compendium: Management of Viral Hemorrhagic Fever (Viral Fever), Involving Its Pathogenesis

The term "Viral Hemorrhagic Fever" (VHF) describes a severe feverish sickness characterized by aberrant vascular control, vascular damage, and hemorrhagic symptoms. Multiple viruses belonging to distinct families are the cause of this illness. The viruses that cause VHF are categorized into seven distinct families according to the International Committee on Taxonomy of Viruses' most recent classification: Hantaviridae, Nairoviridae, Filoviridae, Phenuiviridae, Paramyxoviridae, Arenavidae, and Flaviviridae are the families involved. The concept of virus hemorrhagic fevers (VHFs) originated in the 1930s when Soviet researchers were studying hantaviral hemorrhagic fever (HF) with renal dysfunction. Dengue fever/Dengue haemorrhagic fever and Kyasanur forest sickness are the two most common viral hemorrhagic fevers (VHF) in India that are transmitted by arthropod vectors. The diagnosis of community-acquired pneumonia (CCHF) in India is greatly hampered by the co-occurring symptoms of hemorrhagic fevers such as dengue, Kyasanur forest sickness, Hantavirus hemorrhagic fever, and other illnesses such as leptospirosis, meningococcal infections, and malaria. The pathophysiology, aetiology, diagnosis, treatment, symptoms, and indicators of virus hemorrhagic fevers (VHFs) are all covered in this review article.

Meningococcal meningitis in Spain in the Horizon 2030: A position paper.

Meningococcal meningitis (MM) and invasive meningococcal disease remain a major public health problem that generates enormous public alarm. It is caused by Neisseria meningitidis, a Gram-negative diplococcus with an enormous capacity for acute and rapidly progressive disease, both episodic and epidemic in nature, with early diagnosis and treatment playing a major role. It occurs at any age, but is most common in children under 5 years of age followed by adolescents. Although most cases occur in healthy people, the incidence is higher in certain risk groups. Despite advances in reducing the incidence, it is estimated that in 2017 there were around 5 million new cases of MM worldwide, causing approximately 290,000 deaths and a cumulative loss of about 20,000,000 years of healthy life. In Spain, in the 2021/22 season, 108 microbiologically confirmed cases of MM were reported, corresponding to an incidence rate of 0.23 cases per 100,000 inhabitants. This is a curable and, above all, vaccine-preventable disease, for which the World Health Organisation has drawn up a roadmap with the aim of reducing mortality and sequelae by 2030. For all these reasons, the Illustrious Official College of Physicians of Madrid (ICOMEM) and the Medical Associations of 8 other provinces of Spain, have prepared this opinion document on the situation of MM in Spain and the resources and preparation for the fight against it in our country. The COVID-19 and Emerging Pathogens Committee of ICOMEM has invited experts in the field to participate in the elaboration of this document.

Determine the factors affecting the time to recovery of children with bacterial meningitis at Jigjiga university referral hospital in the Somali Regional State of Ethiopia: using the parametric shared frailty and AFT models

BackgroundNeisseria meningitides, Streptococcus pneumonia, and hemophilic influenza type B are frequently linked to bacterial meningitis (BM) in children. It’s an infectious sickness that kills and severely mobilizes children. For a variety of reasons, bacterial meningitis remains a global public health concern; most cases and deaths are found in Sub-Saharan Africa, particularly in Ethiopia. Even though vaccination has made BM more preventable, children worldwide are still severely harmed by this serious illness. Age, sex, and co-morbidity are among the risk variables for BM that have been found. Therefore, the main objective of this study was to identify the variables influencing the time to recovery for children with bacterial meningitis at Jigjiga University referral hospital in the Somali regional state of Ethiopia.MethodA retrospective cohort of 535 children with bacterial meningitis who received antibiotic treatment was the subject of this study. Parametric Shared Frailty ty and the AFT model were employed with log likelihood, BIC, and AIC methods of model selection. The frailty models all employed the patients' kebele as a clustering factor.ResultsThe number of cases of BM declined in young children during the duration of the 2 year, 11 month study period, but not in the elderly. Streptococcus pneumonia (50%), hemophilic influenza (30.5%), and Neisseria meningitides (15%) were the most frequent causes of BM. The time to recovery of patients from bacteria was significantly influenced by the covariates male patients (ϕ = 0.927; 95% CI (0.866, 0.984); p-value = 0.014), patients without a vaccination history (ϕ = 0.898; 95% CI (0.834, 0.965); P value = 0.0037), and patients who were not breastfeeding (ϕ = 0.616; 95% CI (0.404, 0.039); P-value = 0.024). The recovery times for male, non-breastfed children with bacterial patients are 7.9 and 48.4% shorter, respectively. In contrast to children with comorbidity, the recovery time for children without comorbidity increased by 8.7%.ConclusionAge group, sex, vaccination status, co-morbidity, breastfeeding, and medication regimen were the main determinant factors for the time to recovery of patients with bacterial meningitis. Patients with co-morbidities require the doctor at Jigjiga University Referral Hospital to pay close attention to them.

Cryo-EM structures of type IV pili complexed with nanobodies reveal immune escape mechanisms

Type IV pili (T4P) are prevalent, polymeric surface structures in pathogenic bacteria, making them ideal targets for effective vaccines. However, bacteria have evolved efficient strategies to evade type IV pili-directed antibody responses. Neisseria meningitidis are prototypical type IV pili-expressing Gram-negative bacteria responsible for life threatening sepsis and meningitis. This species has evolved several genetic strategies to modify the surface of its type IV pili, changing pilin subunit amino acid sequence, nature of glycosylation and phosphoforms, but how these modifications affect antibody binding at the structural level is still unknown. Here, to explore this question, we determine cryo-electron microscopy (cryo-EM) structures of pili of different sequence types with sufficiently high resolution to visualize posttranslational modifications. We then generate nanobodies directed against type IV pili which alter pilus function in vitro and in vivo. Cryo-EM in combination with molecular dynamics simulation of the nanobody-pilus complexes reveals how the different types of pili surface modifications alter nanobody binding. Our findings shed light on the impressive complementarity between the different strategies used by bacteria to avoid antibody binding. Importantly, we also show that structural information can be used to make informed modifications in nanobodies as countermeasures to these immune evasion mechanisms.

Penbraya: A pentavalent meningococcal vaccine.

The FDA has licensed Penbraya (Pfizer), a pentavalent polysaccharide conjugate meningococcal vaccine, for prevention of invasive meningococcal disease caused by Neisseria meningitidis serogroups A, B, C, W, or Y (MenABCWY) in persons 10-25 years old. Penbraya is the only meningococcal vaccine that contains all five of these serogroups. Two quadrivalent polysaccharide conjugate meningococcal vaccines containing serogroups A, C, W, and Y (MenACWY; Menveo, MenQuadfi) and two meningococcal serogroup B vaccines (MenB; Bexsero, Trumenba) are available in the US.