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Presa J, Findlow J, Zimet GD. Meningococcal Vaccination of Adolescents in the United States: Past Successes and Future Considerations. J Adolesc Health 2024; 74:1068-1077. [PMID: 38430074 DOI: 10.1016/j.jadohealth.2024.01.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 12/20/2023] [Accepted: 01/10/2024] [Indexed: 03/03/2024]
Abstract
Invasive meningococcal disease (IMD) is a rare but serious illness, and adolescents and young adults in the United States are at increased risk. Here, we discuss US IMD history and how successful disease prevention through routine vaccination against the most common disease-causing serogroups (A, B, C, W, and Y) can inform future recommendations. Before the introduction of quadrivalent meningococcal conjugate (MenACWY) vaccines, most US cases of IMD were caused by serogroups B, C, and Y. After recommendation by the Advisory Committee on Immunization Practices for routine MenACWY vaccination of 11-12-year-olds in 2005, followed by a 2010 booster recommendation, MenCWY disease incidence declined dramatically, and vaccine coverage remains high. Two serogroup B (MenB) vaccines are licensed in the United States, but uptake is low compared with MenACWY vaccines, likely because Advisory Committee on Immunization Practices recommends MenB vaccination subject to shared clinical decision-making rather than routinely for all adolescents. The proportion of adolescent IMD caused by MenB has now increased. Pentavalent vaccines that protect against serogroups A, B, C, W, and Y may provide an optimal strategy for improving vaccination rates to ultimately reduce MenB incidence while maintaining the historically low rates of IMD caused by serogroups A, C, W, and Y.
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Affiliation(s)
- Jessica Presa
- Vaccines Medical Development & Scientific/Clinical Affairs, Pfizer Inc, Collegeville, Pennsylvania.
| | - Jamie Findlow
- Vaccines Medical Development & Scientific/Clinical Affairs, Pfizer Ltd, Surrey, United Kingdom
| | - Gregory D Zimet
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana
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Tondé I, Tranchot-Diallo J, Kambiré D, Ky-Ba A, Sanou M, Sanou I, Ouédraogo-Traoré R. Genomic and phenotypic diagnosis of bacterial meningitis in 25 health districts in Burkina Faso between January 2016 and December 2019. Infect Dis Now 2024; 54:104805. [PMID: 37827376 DOI: 10.1016/j.idnow.2023.104805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/16/2023] [Accepted: 10/04/2023] [Indexed: 10/14/2023]
Affiliation(s)
- Issa Tondé
- Centre Hospitalier Universitaire Pédiatrique Charles De Gaulle, Burkina Faso; Université Joseph Ki-Zerbo, Burkina Faso.
| | - Juliette Tranchot-Diallo
- Centre Muraz, Institut National de Santé Publique (INSP), Burkina Faso; Université Nazi Boni, Burkina Faso
| | | | - Absatou Ky-Ba
- Université Joseph Ki-Zerbo, Burkina Faso; Centre Hospitalier Universitaire du District sanitaire de Bogodogo, Burkina Faso
| | - Mahamoudou Sanou
- Centre Hospitalier Universitaire Pédiatrique Charles De Gaulle, Burkina Faso; Université Joseph Ki-Zerbo, Burkina Faso
| | - Idrissa Sanou
- Université Joseph Ki-Zerbo, Burkina Faso; Centre Hospitalier Universitaire Tengandogo, Burkina Faso
| | - Rasmata Ouédraogo-Traoré
- Centre Hospitalier Universitaire Pédiatrique Charles De Gaulle, Burkina Faso; Université Joseph Ki-Zerbo, Burkina Faso
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Yan L, Tang C, Cai Y, Nong J, Zhang K, Zhu L, Wang P, Wu L, Zhao F, Hu S. Ultra-efficient multiple cross displacement amplification-lateral flow biosensor (MCDA-LFB) for serogroup identification of prevalent Neisseria meningitidis. Anal Biochem 2022; 654:114740. [PMID: 35623396 DOI: 10.1016/j.ab.2022.114740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 11/18/2022]
Abstract
Meningococcal disease caused by Neisseria meningitidis remains a major global public health concern. Serogroup A, B, C and W135 were the major disease-causing serogroups. It is vital to timely and efficiently detect and differentiate these four serogroups. Herein, we developed multiple cross displacement amplification-lateral flow biosensor (MCDA-LFB) assays targeting ctrA, sacB, siaD, siaD and synG gene respectively for detection and subtyping of four N. meningitidis serogroups. This assay utilizes LFB to detect FITC and biotin-labeled target amplicons produced by MCDA through double antibody sandwich principle, to allow sensitive and specific detection under a constant temperature. The detection limit was as low as 10 fg or 100 fg genomic DNA in pure cultures and 5.5 CFUs or 36 CFUs in spiked cerebrospinal fluid (CSF) specimens, which were overall 100 to 1000-fold more sensitive than conventional PCR. High specificity of these assays was also validated through type strains and clinical isolates, with no cross-reactions. MCDA-LFB testing procedure can be finished within 1 h. In conclusion, the N. meningitidis- and serogroup-MCDA-LFB assays established in this study are simple, rapid and efficient, providing valuable molecular methods for diagnosis and surveillance of meningococcal disease, especially in resource-limited regions and when specimen culture fails.
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Affiliation(s)
- Linlin Yan
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Chong Tang
- Department of Orthopaedic Surgery, Peking University Shougang Hospital, Beijing, 100144, China
| | - Yu Cai
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Jinqing Nong
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Ke Zhang
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Linlin Zhu
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Pengfei Wang
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Lei Wu
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Fan Zhao
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China.
| | - Shoukui Hu
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China.
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Neisseria meningitidis Serogroup C Clonal Complex 10217 Outbreak in West Kpendjal Prefecture, Togo 2019. Microbiol Spectr 2022; 10:e0192321. [PMID: 35234504 PMCID: PMC8941916 DOI: 10.1128/spectrum.01923-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Togo has reported seasonal meningitis outbreaks caused by non-Neisseria meningitidis serogroup A (NmA) pathogens since the introduction of meningococcal serogroup A conjugate vaccine (MACV, MenAfriVac) in 2014. From 2016 to 2017, NmW caused several outbreaks. In early 2019, a NmC outbreak was detected in the Savanes region of Togo and its investigation is described here. Under case-based surveillance, epidemiological and clinical data, and cerebrospinal fluid specimens were collected for every suspected case of meningitis. Specimens were tested for meningitis pathogens using confirmatory microbiological and molecular methods. During epidemic weeks 9 to 15, 199 cases were reported, with 179 specimens being available for testing and 174 specimens (97.2%) were tested by at least one confirmatory method. The NmC was the predominant pathogen confirmed (93.9%), belonging to sequence type (ST)-9367 of clonal complex (CC) 10217. All NmC cases were localized to the West Kpendjal district of the Savanes region with attack rates ranging from 4.1 to 18.8 per 100,000 population and case fatality rates ranging up to 2.2% during weeks 9 to 15. Of the 93 NmC confirmed cases, 63.4% were males and 88.2% were in the 5 to 29 age group. This is the first report of a NmC meningitis outbreak in Togo. The changing epidemiology of bacterial meningitis in the meningitis belt post-MACV highlights the importance of monitoring of emerging strain and country preparedness for outbreaks in the region. IMPORTANCE The recent emergence of an invasive NmC strain in Togo is an example of the changing bacterial meningitis epidemiology in the meningitis belt post-MACV. The current epidemiology includes the regional circulation of various non-NmA serogroups, which emphasizes the need for effective molecular surveillance, laboratory diagnosis, and a multivalent vaccine that is effective against all serogroups in circulation.
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Walter S, Gil-Prieto R, Gil-Conesa M, Rodriguez-Caravaca G, San Román J, Gil de Miguel A. Hospitalizations related to meningococcal infection in Spain from 1997 to 2018. BMC Infect Dis 2021; 21:1215. [PMID: 34872512 PMCID: PMC8650227 DOI: 10.1186/s12879-021-06916-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 11/17/2021] [Indexed: 11/25/2022] Open
Abstract
Background Baseline hospitalization, mortality, and in-hospital fatality rates for meningococcal infection are required to evaluate preventive interventions, such as the inclusion of the conjugated quadrivalent meningococcal vaccine and serogroup B based protein vaccines. Methods All meningococcal infection–related hospitalizations in any diagnostic position in Spain from 1st January 1997 through 31st December 2018 were analysed. The annual hospitalization rate, mortality rate and case-fatality rate were calculated. Results The average hospitalization rate for meningococcal infection was 1.64 (95% CI 1.61 to 1.66) hospitalizations per 100,000 inhabitants during the study period and significantly decreased from 1997 to 2018. Hospitalizations for meningococcal infection decreased significantly with age and were concentrated in children under 5 years of age (46%). The hospitalization rates reached 29 per 100,000 and 24 per 100,000 children under 1 and 2 years of age, respectively. The in-hospital case-fatality rate was 7.45% (95% CI 7.03 to 7.86). Thirty percent of the deaths occurred in children under 5 years of age, and more than half occurred in adults. The case fatality rate increased significantly with age (p < 0.001). Conclusion It is necessary to maintain epidemiological surveillance of meningococcal infection to determine the main circulating serogroups involved, track their evolution, and evaluate preventive measures whose effectiveness must be assessed in all age groups.
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Affiliation(s)
- Stefan Walter
- Department of Medicine & Public Health, Universidad Rey Juan Carlos, Avda. Atenas S/N, 28922, Madrid, Spain
| | - Ruth Gil-Prieto
- Department of Medicine & Public Health, Universidad Rey Juan Carlos, Avda. Atenas S/N, 28922, Madrid, Spain.
| | - Mario Gil-Conesa
- Preventive Medicine Service, Hospital Universitario Fundación Alcorcón, Madrid, Spain.,PhD Student Programa de Doctorado en Ciencias de la Salud, Universidad Rey Juan Carlos, Madrid, Spain
| | | | - Jesús San Román
- Department of Medicine & Public Health, Universidad Rey Juan Carlos, Avda. Atenas S/N, 28922, Madrid, Spain
| | - Angel Gil de Miguel
- Department of Medicine & Public Health, Universidad Rey Juan Carlos, Avda. Atenas S/N, 28922, Madrid, Spain
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Exploring the Ability of Meningococcal Vaccines to Elicit Mucosal Immunity: Insights from Humans and Mice. Pathogens 2021; 10:pathogens10070906. [PMID: 34358056 PMCID: PMC8308890 DOI: 10.3390/pathogens10070906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 07/01/2021] [Accepted: 07/09/2021] [Indexed: 12/16/2022] Open
Abstract
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.
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MacAlasdair N, Pesonen M, Brynildsrud O, Eldholm V, Kristiansen PA, Corander J, Caugant DA, Bentley SD. The effect of recombination on the evolution of a population of Neisseria meningitidis. Genome Res 2021; 31:1258-1268. [PMID: 34108268 PMCID: PMC8256868 DOI: 10.1101/gr.264465.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 04/22/2021] [Indexed: 12/02/2022]
Abstract
Neisseria meningitidis (the meningococcus) is a major human pathogen with a history of high invasive disease burden, particularly in sub-Saharan Africa. Our current understanding of the evolution of meningococcal genomes is limited by the rarity of large-scale genomic population studies and lack of in-depth investigation of the genomic events associated with routine pathogen transmission. Here, we fill this knowledge gap by a detailed analysis of 2839 meningococcal genomes obtained through a carriage study of over 50,000 samples collected systematically in Burkina Faso, West Africa, before, during, and after the serogroup A vaccine rollout, 2009-2012. Our findings indicate that the meningococcal genome is highly dynamic, with highly recombinant loci and frequent gene sharing across deeply separated lineages in a structured population. Furthermore, our findings illustrate how population structure can correlate with genome flexibility, as some lineages in Burkina Faso are orders of magnitude more recombinant than others. We also examine the effect of selection on the population, in particular how it is correlated with recombination. We find that recombination principally acts to prevent the accumulation of deleterious mutations, although we do also find an example of recombination acting to speed the adaptation of a gene. In general, we show the importance of recombination in the evolution of a geographically expansive population with deep population structure in a short timescale. This has important consequences for our ability to both foresee the outcomes of vaccination programs and, using surveillance data, predict when lineages of the meningococcus are likely to become a public health concern.
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Affiliation(s)
- Neil MacAlasdair
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Maiju Pesonen
- Oslo Centre for Biostatistics and Epidemiology (OCBE), Oslo University Hospital Research Support Services, Blindern, 0317 Oslo, Norway
| | - Ola Brynildsrud
- Division for Infection Control and Environmental Health, Norwegian Institute of Public Health, 0213 Oslo, Norway
- Department of Food Safety and Infection Biology, Faculty of Veterinary Science, Norwegian University of Life Science, 0454 Oslo, Norway
| | - Vegard Eldholm
- Division for Infection Control and Environmental Health, Norwegian Institute of Public Health, 0213 Oslo, Norway
| | - Paul A Kristiansen
- Division for Infection Control and Environmental Health, Norwegian Institute of Public Health, 0213 Oslo, Norway
| | - Jukka Corander
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge CB10 1SA, United Kingdom
- University of Oslo, Department of Biostatistics, Blindern, 0317 Oslo, Norway
- Helsinki Institute for Information Technology HIIT, Department of Mathematics and Statistics, University of Helsinki, 00014 Helsinki, Finland
| | - Dominique A Caugant
- Division for Infection Control and Environmental Health, Norwegian Institute of Public Health, 0213 Oslo, Norway
- Department of Community Medicine, Faculty of Medicine, University of Oslo, Blindern, 0316 Oslo, Norway
| | - Stephen D Bentley
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge CB10 1SA, United Kingdom
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Sharma S, Acharya J, Caugant DA, Aryal S, Banjara MR, Ghimire P, Singh A. Meningococcal Carriage among Household Contacts of Patients with Invasive Meningococcal Disease in Kathmandu, Nepal: A Longitudinal Study. Pathogens 2021; 10:pathogens10070781. [PMID: 34206153 PMCID: PMC8308540 DOI: 10.3390/pathogens10070781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/11/2021] [Accepted: 06/15/2021] [Indexed: 11/24/2022] Open
Abstract
Because asymptomatic carriers are key source of transmission, information on meningococcal carriage in the community provides a scientific basis for appropriate preventive/control strategies. This longitudinal study (January 2017–December 2019) aimed to estimate carriage rate of meningococci among household contacts of meningococcal meningitis cases within Kathmandu Valley, Nepal. Throat swab samples were collected at first visit from each person in households, twice a month for up to 2 months and subsequently on a monthly basis for a further 4 months. Altogether, 1125 throat samples were processed by conventional culture for the identification of meningococci. To the best of our knowledge, this is the first longitudinal study on meningococcal carriage in Nepal. The meningococcal carriage rate among household contacts was 15%. All carriers were aged 19 years or older. There was no statistically significant gender difference. The duration of carriage was 60 days. Twenty of 36 isolates belonged to serogroup A, and 16 were non-serogroupable (NG). Serogroups isolated from the same individuals did not change within the follow-up period. All meningococcal isolates over the past 38 years in Nepal that have been reported in previous studies have belonged to serogroup A. The detection of NG meningococcal isolates in apparently healthy household contacts clearly indicates the importance of vigilance through surveillance and periodic in-depth studies.
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Affiliation(s)
- Supriya Sharma
- Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu 44600, Nepal; (M.R.B.); (P.G.); (A.S.)
- Correspondence: ; Tel.: +977-98-4150-8496
| | - Jyoti Acharya
- National Public Health Laboratory, Teku, Kathmandu 44600, Nepal;
| | - Dominique A. Caugant
- WHO Collaborating Centre for Reference and Research on Meningococci, Norwegian Institute of Public Health, 0213 Oslo, Norway;
| | | | - Megha Raj Banjara
- Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu 44600, Nepal; (M.R.B.); (P.G.); (A.S.)
| | - Prakash Ghimire
- Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu 44600, Nepal; (M.R.B.); (P.G.); (A.S.)
| | - Anjana Singh
- Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu 44600, Nepal; (M.R.B.); (P.G.); (A.S.)
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Gao F, Beresford N, Lockyer K, Burkin K, Rigsby P, Bolgiano B. Saccharide dosage content of meningococcal polysaccharide conjugate vaccines determined using WHO International Standards for serogroup A, C, W, Y and X polysaccharides. Biologicals 2021; 70:53-58. [PMID: 33518432 DOI: 10.1016/j.biologicals.2021.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/13/2021] [Accepted: 01/17/2021] [Indexed: 10/22/2022] Open
Abstract
Potency of meningococcal polysaccharide-protein conjugate vaccines relies on the polysaccharide content to prevent meningitis. NIBSC, as the official national control laboratory in UK, analysed ten different mono- and multi-meningococcal conjugate vaccines, using established International Standards for meningococcal serogroups A, C, W, Y and X, by resorcinol or HPAEC-PAD assay. Most saccharide contents were within ±20% of their claimed content for licensure with taking different O-acetylation levels into consideration, with only MenC content in two vaccines below (by 60% and 54%) the labelled value, however, previous study showed different dosage was not necessarily correlated to the immunogenicity of those vaccines. This study demonstrated the use of International Standards to quantify saccharide content in polysaccharide-based vaccines with different percentage of O-acetylation. These International Standards are suitable to serve as either quantitative standard or calibrator of in-house standards, with supplied stability data.
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Affiliation(s)
- Fang Gao
- Division of Bacteriology, National Institute for Biological Standards and Control, Blanche Lane, Potters Bar, Hertfordshire, EN6 3QG, UK.
| | - Nicola Beresford
- Division of Bacteriology, National Institute for Biological Standards and Control, Blanche Lane, Potters Bar, Hertfordshire, EN6 3QG, UK
| | - Kay Lockyer
- Division of Bacteriology, National Institute for Biological Standards and Control, Blanche Lane, Potters Bar, Hertfordshire, EN6 3QG, UK
| | - Karena Burkin
- Division of Bacteriology, National Institute for Biological Standards and Control, Blanche Lane, Potters Bar, Hertfordshire, EN6 3QG, UK
| | - Peter Rigsby
- Biostatistics, National Institute for Biological Standards and Control, Blanche Lane, Potters Bar, Hertfordshire, EN6 3QG, UK
| | - Barbara Bolgiano
- Division of Bacteriology, National Institute for Biological Standards and Control, Blanche Lane, Potters Bar, Hertfordshire, EN6 3QG, UK
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Topaz N, Kristiansen PA, Schmink S, Congo-Ouédraogo M, Kambiré D, Mbaeyi S, Paye M, Sanou M, Sangaré L, Ouédraogo R, Wang X. Molecular insights into meningococcal carriage isolates from Burkina Faso 7 years after introduction of a serogroup A meningococcal conjugate vaccine. Microb Genom 2020; 6:mgen000486. [PMID: 33332261 PMCID: PMC8116689 DOI: 10.1099/mgen.0.000486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 11/10/2020] [Indexed: 11/26/2022] Open
Abstract
In 2010, Burkina Faso completed the first nationwide mass-vaccination campaign of a meningococcal A conjugate vaccine, drastically reducing the incidence of disease caused by serogroup A meningococci. Since then, other strains, such as those belonging to serogroups W, X and C, have continued to cause outbreaks within the region. A carriage study was conducted in 2016 and 2017 in the country to characterize the meningococcal strains circulating among healthy individuals following the mass-vaccination campaign. Four cross-sectional carriage evaluation rounds were conducted in two districts of Burkina Faso, Kaya and Ouahigouya. Oropharyngeal swabs were collected for the detection of Neisseria meningitidis by culture. Confirmed N. meningitidis isolates underwent whole-genome sequencing for molecular characterization. Among 13 758 participants, 1035 (7.5 %) N. meningitidis isolates were recovered. Most isolates (934/1035; 90.2 %) were non-groupable and primarily belonged to clonal complex (CC) 192 (822/934; 88 %). Groupable isolates (101/1035; 9.8 %) primarily belonged to CCs associated with recent outbreaks in the region, such as CC11 (serogroup W) and CC10217 (serogroup C); carried serogroup A isolates were not detected. Phylogenetic analysis revealed several CC11 strains circulating within the country, several of which were closely related to invasive isolates. Three sequence types (STs) were identified among eleven CC10217 carriage isolates, two of which have caused recent outbreaks in the region (ST-10217 and ST-12446). Our results show the importance of carriage studies to track the outbreak-associated strains circulating within the population in order to inform future vaccination strategies and molecular surveillance programmes.
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Affiliation(s)
- Nadav Topaz
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road NE, MS D11, Atlanta, GA 30329, USA
| | - Paul Arne Kristiansen
- Norwegian Institute of Public Health, Oslo, Norway
- Present address: Coalition for Epidemic Preparedness Innovations (CEPI), Oslo, Norway
| | - Susanna Schmink
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road NE, MS D11, Atlanta, GA 30329, USA
| | | | - Dinanibè Kambiré
- Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle, Ouagadougou, Burkina Faso
| | - Sarah Mbaeyi
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road NE, MS D11, Atlanta, GA 30329, USA
| | - Marietou Paye
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road NE, MS D11, Atlanta, GA 30329, USA
| | - Mahamoudou Sanou
- Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle, Ouagadougou, Burkina Faso
| | - Lassana Sangaré
- Centre Hospitalier Universitaire Yalgado Ouédraogo, Ouagadougou, Burkina Faso
| | - Rasmata Ouédraogo
- Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle, Ouagadougou, Burkina Faso
| | - Xin Wang
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road NE, MS D11, Atlanta, GA 30329, USA
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11
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Mbaeyi S, Sampo E, Dinanibè K, Yaméogo I, Congo-Ouédraogo M, Tamboura M, Sawadogo G, Ouattara K, Sanou M, Kiemtoré T, Dioma G, Sanon B, Somlaré H, Kyetega A, Ba AK, Aké F, Tarbangdo F, Aboua FA, Donnou Y, Kamaté I, Patel JC, Schmink S, Spiller MW, Topaz N, Novak R, Wang X, Bicaba B, Sangaré L, Ouédraogo-Traoré R, Kristiansen PA. Meningococcal carriage 7 years after introduction of a serogroup A meningococcal conjugate vaccine in Burkina Faso: results from four cross-sectional carriage surveys. THE LANCET. INFECTIOUS DISEASES 2020; 20:1418-1425. [PMID: 32653071 PMCID: PMC7689286 DOI: 10.1016/s1473-3099(20)30239-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/05/2020] [Accepted: 03/12/2020] [Indexed: 01/24/2023]
Abstract
BACKGROUND In the first 2 years after a nationwide mass vaccination campaign of 1-29-year-olds with a meningococcal serogroup A conjugate vaccine (MenAfriVac) in Burkina Faso, carriage and disease due to serogroup A Neisseria meningitidis were nearly eliminated. We aimed to assess the long-term effect of MenAfriVac vaccination on meningococcal carriage and herd immunity. METHODS We did four cross-sectional studies of meningococcal carriage in people aged 9 months to 36 years in two districts of Burkina Faso between May 2, 2016, and Nov 6, 2017. Demographic information and oropharyngeal swabs were collected. Meningococcal isolates were characterised using whole-genome sequencing. FINDINGS Of 14 295 eligible people, 13 758 consented and had specimens collected and laboratory results available, 1035 of whom were meningococcal carriers. Accounting for the complex survey design, prevalence of meningococcal carriage was 7·60% (95% CI 5·67-9·52), including 6·98% (4·86-9·11) non-groupable, 0·48% (0·01-0·95) serogroup W, 0·10% (0·01-0·18) serogroup C, 0·03% (0·00-0·80) serogroup E, and 0% serogroup A. Prevalence ranged from 5·44% (95% CI 4·18-6·69) to 9·14% (6·01-12·27) by district, from 4·67% (2·71-6·64) to 11·17% (6·75-15·59) by round, and from 3·39% (0·00-8·30) to 10·43% (8·08-12·79) by age group. By clonal complex, 822 (88%) of 934 non-groupable isolates were CC192, all 83 (100%) serogroup W isolates were CC11, and nine (69%) of 13 serogroup C isolates were CC10217. INTERPRETATION Our results show the continued effect of MenAfriVac on serogroup A meningococcal carriage, for at least 7 years, among vaccinated and unvaccinated cohorts. Carriage prevalence of epidemic-prone serogroup C CC10217 and serogroup W CC11 was low. Continued monitoring of N meningitidis carriage will be crucial to further assess the effect of MenAfriVac and inform the vaccination strategy for future multivalent meningococcal vaccines. FUNDING Bill & Melinda Gates Foundation and Gavi, the Vaccine Alliance.
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Affiliation(s)
- Sarah Mbaeyi
- National Center for Immunization and Respiratory Diseases, US Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | | | - Kambiré Dinanibè
- Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle, Ouagadougou, Burkina Faso
| | - Issaka Yaméogo
- Direction de la Protection de la Santé de la Population, Burkina Faso Ministry of Health, Ouagadougou, Burkina Faso
| | | | - Mamadou Tamboura
- Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle, Ouagadougou, Burkina Faso
| | - Guetawendé Sawadogo
- Direction de la Protection de la Santé de la Population, Burkina Faso Ministry of Health, Ouagadougou, Burkina Faso
| | - Kalifa Ouattara
- Centre Hospitalier Universitaire de Yalgado Ouédraogo, Ouagadougou, Burkina Faso
| | - Mahamadou Sanou
- Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle, Ouagadougou, Burkina Faso
| | - Tanga Kiemtoré
- Direction de la Protection de la Santé de la Population, Burkina Faso Ministry of Health, Ouagadougou, Burkina Faso
| | - Gerard Dioma
- Centre Hospitalier Universitaire de Yalgado Ouédraogo, Ouagadougou, Burkina Faso
| | - Barnabé Sanon
- Centre Hospitalier Régional de Kaya, Kaya, Burkina Faso
| | - Hermann Somlaré
- Centre Hospitalier Universitaire de Yalgado Ouédraogo, Ouagadougou, Burkina Faso
| | - Augustin Kyetega
- Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle, Ouagadougou, Burkina Faso
| | - Absatou Ky Ba
- Centre Hospitalier Universitaire du Bogodogo, Ouagadougou, Burkina Faso
| | - Flavien Aké
- Davycas International, Gounghin Petit-Paris, Ouagadougou, Burkina Faso
| | - Félix Tarbangdo
- Davycas International, Gounghin Petit-Paris, Ouagadougou, Burkina Faso
| | | | - Yvette Donnou
- Davycas International, Gounghin Petit-Paris, Ouagadougou, Burkina Faso
| | - Idrissa Kamaté
- World Health Organization, Intercountry Support Team, Ouagadougou, Burkina Faso
| | - Jaymin C Patel
- National Center for Immunization and Respiratory Diseases, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Susanna Schmink
- National Center for Immunization and Respiratory Diseases, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Michael W Spiller
- National Center for Immunization and Respiratory Diseases, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Nadav Topaz
- National Center for Immunization and Respiratory Diseases, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Ryan Novak
- National Center for Immunization and Respiratory Diseases, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Xin Wang
- National Center for Immunization and Respiratory Diseases, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Brice Bicaba
- Direction de la Protection de la Santé de la Population, Burkina Faso Ministry of Health, Ouagadougou, Burkina Faso
| | - Lassana Sangaré
- Centre Hospitalier Universitaire de Yalgado Ouédraogo, Ouagadougou, Burkina Faso
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12
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Herd Protection against Meningococcal Disease through Vaccination. Microorganisms 2020; 8:microorganisms8111675. [PMID: 33126756 PMCID: PMC7693901 DOI: 10.3390/microorganisms8111675] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/26/2020] [Accepted: 10/28/2020] [Indexed: 12/28/2022] Open
Abstract
Reduction in the transmission of Neisseria meningitidis within a population results in fewer invasive disease cases. Vaccination with meningococcal vaccines composed of high weight capsular polysaccharide without carrier proteins has minimal effect against carriage or the acquisition of carriage. Conjugate vaccines, however, elicit an enhanced immune response which serves to reduce carriage acquisition and hinder onwards transmission. Since the 1990s, several meningococcal conjugate vaccines have been developed and, when used in age groups associated with higher carriage, they have been shown to provide indirect protection to unvaccinated cohorts. This herd protective effect is important in enhancing the efficiency and impact of vaccination. Studies are ongoing to assess the effect of protein-based group B vaccines on carriage; however, current data cast doubt on their ability to reduce transmission.
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13
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Steurer LM, Hetzmannseder M, Willinger B, Starzengruber P, Mikula C, Kormann-Klement A, Weber M, Berger A, Grill A. Pharyngeal carriage rates of Neisseria meningitidis in health care professionals at a tertiary university pediatric hospital. Eur J Clin Microbiol Infect Dis 2020; 39:1703-1709. [PMID: 32333221 PMCID: PMC7427699 DOI: 10.1007/s10096-020-03894-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 04/01/2020] [Indexed: 12/20/2022]
Abstract
Pharyngeal carriage is the reservoir for Neisseria meningitidis in the population and the first step in disease transmission. Especially in young infants and adolescents, N. meningitidis can cause serious invasive infection with high fatality rates and high rates of long-term sequelae among survivors. The aim of this study was to determine N. meningitidis colonization rates in asymptomatic health care professionals at a tertiary university pediatric hospital and to identify risk factors for carriage. This cross-sectional meningococcal carriage survey was conducted between April and October 2018 at the Medical University of Vienna. Individuals working as nurses, pediatricians, or medical students were enrolled. Oropharyngeal swabs were directly plated onto selective agar plates and conventional culture was used for bacterial identification. Meningococcal isolates were further characterized using whole-genome sequencing. A total of 437 oropharyngeal specimens were collected. Overall, meningococcal carriage prevalence was 1.14% (5/437), with 0.7% (3/437) for capsular genotype B, and 0.5% (2/437) for capsular genotype W. Mean age of carriers was significantly lower than of non-carriers (24.2 vs. 35.8; p = 0.004). The highest carriage rate of 4.4% (4/91) was found in the age group 18–25. Carriage was negatively associated with age and timespan working in pediatrics. This is the first study evaluating the prevalence of Neisseria meningitidis carriage in health care professionals working in Pediatrics and Adolescent Medicine. Carriage was in general lower than expected for all age groups, implicating a low risk of meningococcal transmission via this population.
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Affiliation(s)
- Lisa-Maria Steurer
- Department of Pediatrics and Adolescent Medicine, Division of Neonatology, Pediatric Intensive Care Medicine and Neuropediatrics, Medical University of Vienna, Vienna, Austria.
| | - Mathias Hetzmannseder
- Department of Pediatrics and Adolescent Medicine, Division of Neonatology, Pediatric Intensive Care Medicine and Neuropediatrics, Medical University of Vienna, Vienna, Austria
| | - Birgit Willinger
- Department of Laboratory Medicine, Division of Clinical Microbiology, Medical University of Vienna, Vienna, Austria
| | - Peter Starzengruber
- Department of Laboratory Medicine, Division of Clinical Microbiology, Medical University of Vienna, Vienna, Austria
| | - Claudia Mikula
- Institute for Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Graz, Austria
| | - Andrea Kormann-Klement
- Institute for Medical Microbiology and Hygiene, Austrian Agency for Health and Food Safety, Graz, Austria
| | - Michael Weber
- Section for Medical Statistics, CeMSIIS, Medical University of Vienna, Vienna, Austria
| | - Angelika Berger
- Department of Pediatrics and Adolescent Medicine, Division of Neonatology, Pediatric Intensive Care Medicine and Neuropediatrics, Medical University of Vienna, Vienna, Austria
| | - Agnes Grill
- Department of Pediatrics and Adolescent Medicine, Division of Neonatology, Pediatric Intensive Care Medicine and Neuropediatrics, Medical University of Vienna, Vienna, Austria
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14
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Aye AMM, Bai X, Borrow R, Bory S, Carlos J, Caugant DA, Chiou CS, Dai VTT, Dinleyici EC, Ghimire P, Handryastuti S, Heo JY, Jennison A, Kamiya H, Tonnii Sia L, Lucidarme J, Marshall H, Putri ND, Saha S, Shao Z, Sim JHC, Smith V, Taha MK, Van Thanh P, Thisyakorn U, Tshering K, Vázquez J, Veeraraghavan B, Yezli S, Zhu B. Meningococcal disease surveillance in the Asia-Pacific region (2020): The global meningococcal initiative. J Infect 2020; 81:698-711. [PMID: 32730999 DOI: 10.1016/j.jinf.2020.07.025] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/17/2020] [Accepted: 07/24/2020] [Indexed: 12/20/2022]
Abstract
The degree of surveillance data and control strategies for invasive meningococcal disease (IMD) varies across the Asia-Pacific region. IMD cases are often reported throughout the region, but the disease is not notifiable in some countries, including Myanmar, Bangladesh and Malaysia. Although there remains a paucity of data from many countries, specific nations have introduced additional surveillance measures. The incidence of IMD is low and similar across the represented countries (<0.2 cases per 100,000 persons per year), with the predominant serogroups of Neisseria meningitidis being B, W and Y, although serogroups A and X are present in some areas. Resistance to ciprofloxacin is also of concern, with the close monitoring of antibiotic-resistant clonal complexes (e.g., cc4821) being a priority. Meningococcal vaccination is only included in a few National Immunization Programs, but is recommended for high-risk groups, including travellers (such as pilgrims) and people with complement deficiencies or human immunodeficiency virus (HIV). Both polysaccharide and conjugate vaccines form part of recommendations. However, cost and misconceptions remain limiting factors in vaccine uptake, despite conjugate vaccines preventing the acquisition of carriage.
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Affiliation(s)
| | - Xilian Bai
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester M13 9WZ, UK.
| | - Ray Borrow
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester M13 9WZ, UK.
| | | | - Josefina Carlos
- University of the East Ramon Magsaysay Memorial Medical Center, Quezon City, Philippines
| | | | | | - Vo Thi Trang Dai
- Department of Microbiology and Immunology, Pasteur Institute of Ho Chi Minh City, Ho Chi Minh City, Viet Nam
| | | | | | | | - Jung Yeon Heo
- Department of Infectious Diseases, Ajou University School of Medicine, Suwon, South Korea.
| | | | - Hajime Kamiya
- National Institute of Infectious Diseases, Tokyo, Japan
| | | | - Jay Lucidarme
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester M13 9WZ, UK.
| | - Helen Marshall
- Robinson Research Institute and department of Paediatrics, Adelaide Medical School, The University of Adelaide, Adelaide, Australia.
| | - Nina Dwi Putri
- Dr Cipto Mangunkusumo National Central Hospital, Jakarta, Indonesia
| | - Senjuti Saha
- Child Health Research Foundation, Mohammadpur, Dhaka1207, Bangladesh.
| | - Zhujun Shao
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
| | | | - Vinny Smith
- Meningitis Research Foundation, Bristol, UK.
| | | | - Phan Van Thanh
- Department of Microbiology and Immunology, Pasteur Institute of Ho Chi Minh City, Ho Chi Minh City, Viet Nam
| | - Usa Thisyakorn
- Tropical Medicine Cluster, Chulalongkorn University, Bangkok, Thailand
| | - Kinley Tshering
- Jigme Dorji Wangchuck National Referral Hospital, Thimpu, Bhutan
| | - Julio Vázquez
- National Reference Laboratory for Meningococci, Institute of Health Carlos III, Spain.
| | | | - Saber Yezli
- Global Center for Mass Gatherings Medicine, Saudi Arabia
| | - Bingqing Zhu
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
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15
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Abstract
Meningococcal carriage dynamics drive patterns of invasive disease. The distribution of carriage by age has been well described in Europe, but not in the African meningitis belt, a region characterised by frequent epidemics of meningitis. We aimed to estimate the age-specific prevalence of meningococcal carriage by season in the African meningitis belt. We searched PubMed, Web of Science, the Cochrane Library and grey literature for papers reporting carriage of Neisseria meningitidis in defined age groups in the African meningitis belt. We used a mixed-effects logistic regression to model meningococcal carriage prevalence as a function of age, adjusting for season, location and year. Carriage prevalence increased from low prevalence in infants (0.595% in the rainy season, 95% CI 0.482–0.852%) to a broad peak at age 10 (1.94%, 95% CI 1.87–2.47%), then decreased in adolescence. The odds of carriage were significantly increased during the dry season (OR 1.5 95% CI 1.4–1.7) and during outbreaks (OR 6.7 95% CI 1.6–29). Meningococcal carriage in the African meningitis belt peaks at a younger age compared to Europe. This is consistent with contact studies in Africa, which show that children 10–14 years have the highest frequency of contacts. Targeting older children in Africa for conjugate vaccination may be effective in reducing meningococcal transmission.
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16
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Hlozek J, Ravenscroft N, Kuttel MM. Modeling the conformations of Neisseria meningitidis serogroup a CPS and a carba-analogue: Implications for vaccine development. Carbohydr Res 2019; 486:107838. [PMID: 31654945 DOI: 10.1016/j.carres.2019.107838] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/11/2019] [Accepted: 10/15/2019] [Indexed: 10/25/2022]
Abstract
Neisseria meningitidis is a major cause of bacterial meningitis worldwide, especially in Africa. The capsular polysaccharide is the main virulence factor and the target antigen for polysaccharide- and conjugate vaccines. Three tetravalent conjugate vaccines against serogroups A, C, Y and W have been licensed and the monovalent MenAfriVac® was introduced to address the high burden of serogroup A disease in the Meningitis Belt of sub-Saharan Africa. Three of these four vaccines are lyophilized due to the instability of the serogroup A antigen (MenA) in aqueous solution, resulting in a two vial presentation with concomitant additional costs for storage and distribution. Replacement of the saccharide ring oxygen with a methylene group is a promising approach to preparing a stable oligosaccharide MenA analogue (Carba-MenA) vaccine suitable for a liquid formulation. However, to be effective, Carba-MenA must elicit an immune response that is cross-reactive to the native MenA. Here we employ microsecond molecular dynamics simulations of ten repeats of MenA and Carba-MenA to establish that there are significant differences in the conformation and dynamics of these antigens in solution. Carba-MenA has a more random extended, conformation than MenA; MenA has a significant population of compact S-bend conformations that are absent in the analogue. We also find that the disaccharides are poor models of the conformational behaviour of longer chains. This information is relevant for the rational design of optimal analogues for conjugate vaccines.
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Affiliation(s)
- Jason Hlozek
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, South Africa
| | - Neil Ravenscroft
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, South Africa
| | - Michelle M Kuttel
- Department of Computer Science, University of Cape Town, Rondebosch, 7701, South Africa.
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17
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Presa J, Findlow J, Vojicic J, Williams S, Serra L. Epidemiologic Trends, Global Shifts in Meningococcal Vaccination Guidelines, and Data Supporting the Use of MenACWY-TT Vaccine: A Review. Infect Dis Ther 2019; 8:307-333. [PMID: 31347097 PMCID: PMC6702537 DOI: 10.1007/s40121-019-0254-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Indexed: 12/18/2022] Open
Abstract
Neisseria meningitidis is a major cause of meningitis and septicemia with cases, outbreaks, and epidemics reported globally in industrialized and non-industrialized countries. N. meningitidis is categorized into 12 serogroups; however, only 5 serogroups (A, B, C, W, Y) are responsible for the majority of disease. Invasive meningococcal disease (IMD) occurs unpredictably; protection is therefore best achieved by initiating proactive vaccination strategies. Vaccines are currently available for the five main disease-causing serogroups. With the evolution of meningococcal vaccines and changes in IMD epidemiology, different vaccination strategies have been used. Recently, the rapid clonal expansion of meningococcal serogroup W (MenW) has been associated with a change in the national and regional vaccination recommendations from monovalent meningococcal serogroup C vaccines to meningococcal serogroup A, C, W, Y (MenACWY) vaccines in several countries. This review highlights these and other changes in IMD epidemiology and meningococcal vaccination recommendations, summarizes information available for currently available conjugate MenACWY vaccines, and focuses on clinical study data for the most recently approved MenACWY conjugate vaccine, MenACWY vaccine conjugated to tetanus toxoid (MenACWY-TT). MenACWY-TT studies spanned multiple age groups and generally demonstrated safety and immunogenicity in comparison with other meningococcal vaccines and under concomitant administration of other routine vaccines. Continuous updates to meningococcal vaccine recommendations in response to changing epidemiology, as have been undertaken for MenW, are necessary to ensure optimal population protection. FUNDING: Pfizer, Inc.
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Affiliation(s)
- Jessica Presa
- Global Medical Development and Scientific/Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Jamie Findlow
- Medical and Scientific Affairs, International Developed Markets, Pfizer Ltd, Tadworth, Surrey, UK
| | | | | | - Lidia Serra
- Global Medical Development and Scientific/Clinical Affairs, Pfizer Inc, Collegeville, PA, USA.
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18
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Klein NP, Block SL, Essink B, Barbi S, Smolenov I, Keshavan P. Antibody persistence and booster response following MenACWY-CRM vaccination in children as assessed by two different assay methods. Vaccine 2019; 37:4460-4467. [PMID: 31279564 DOI: 10.1016/j.vaccine.2019.06.076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 06/17/2019] [Accepted: 06/24/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND The quadrivalent meningococcal conjugate vaccine MenACWY-CRM has been shown to be immunogenic and well-tolerated in infants and toddlers. We evaluated antibody persistence for up to 4 years after vaccination with MenACWY-CRM in the first years of life and response to a booster dose administered at 60 months of age. METHODS This was phase 3b, open-label, multicenter extension trial (NCT01148017). We assessed by hSBA and rSBA the persistence of antibody responses to serogroups ACWY in 203 healthy 60-month-olds receiving 4 doses of MenACWY-CRM during infancy (ACWY-4 group), or 2 doses at 12/13 and 15 months or 1 dose at 18 months of age (ACWY-2 group). We administered a MenACWY-CRM dose to 224 primed and 45 naïve 60-month-olds and evaluated safety and antibody response 1 month later. RESULTS Antibody persistence measured by both assays was higher in primed than naïve 60-month-olds. The percentages of primed children with hSBA titers ≥8 was low for serogroup A (6-25%) and moderate for serogroups C (27-43%), Y (69-74%) and W (56-69%). For all serogroups, hSBA antibody geometric mean titers (GMTs) tended to be higher in the ACWY-2 than the ACWY-4 group. Post-booster/single dose, ≥96% of primed and ≥73% of naïve children had hSBA titers ≥8 against each serogroup, and hSBA GMTs were higher in primed children. The booster dose was well-tolerated and no safety concern was identified. We further assessed persistence using rSBA across different age groups and detected no overall correlation between rSBA and hSBA titers. CONCLUSIONS Primary vaccination of infants/toddlers with MenACWY-CRM resulted in moderate antibody persistence against serogroups C, W and Y for up to 4 years after the last priming dose. Regardless of priming schedule, a MenACWY-CRM booster dose at 60 months of age induced a robust immune response against all serogroups and was well-tolerated in all children.
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Affiliation(s)
- Nicola P Klein
- Kaiser Permanente Vaccine Study Center, 1 Kaiser Plaza, 16th Floor, Oakland, CA 94612, United States.
| | - Stan L Block
- Kentucky Pediatric and Adult Research, INC, 201 S 5th St, Bardstown, KY 40004, United States
| | - Brandon Essink
- Meridian Clinical Research, 3323 N 107th St, Omaha, NE 6813, United States.
| | - Silvia Barbi
- GSK, Hullenbergweg 81-87, 1101 CL Amsterdam, the Netherlands.
| | - Igor Smolenov
- GSK, Hullenbergweg 81-87, 1101 CL Amsterdam, the Netherlands
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19
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Schuchat A, Anderson LJ, Rodewald LE, Cox NJ, Hajjeh R, Pallansch MA, Messonnier NE, Jernigan DB, Wharton M. Progress in Vaccine-Preventable and Respiratory Infectious Diseases-First 10 Years of the CDC National Center for Immunization and Respiratory Diseases, 2006-2015. Emerg Infect Dis 2019; 24:1178-1187. [PMID: 29916350 PMCID: PMC6038744 DOI: 10.3201/eid2407.171699] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The need for closer linkages between scientific and programmatic areas focused on addressing vaccine-preventable and acute respiratory infections led to establishment of the National Center for Immunization and Respiratory Diseases (NCIRD) at the Centers for Disease Control and Prevention. During its first 10 years (2006–2015), NCIRD worked with partners to improve preparedness and response to pandemic influenza and other emergent respiratory infections, provide an evidence base for addition of 7 newly recommended vaccines, and modernize vaccine distribution. Clinical tools were developed for improved conversations with parents, which helped sustain childhood immunization as a social norm. Coverage increased for vaccines to protect adolescents against pertussis, meningococcal meningitis, and human papillomavirus–associated cancers. NCIRD programs supported outbreak response for new respiratory pathogens and oversaw response of the Centers for Disease Control and Prevention to the 2009 influenza A(H1N1) pandemic. Other national public health institutes might also find closer linkages between epidemiology, laboratory, and immunization programs useful.
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20
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Greenwood BM, Aseffa A, Caugant DA, Diallo K, Kristiansen PA, Maiden MCJ, Stuart JM, Trotter CL. Narrative review of methods and findings of recent studies on the carriage of meningococci and other Neisseria species in the African Meningitis Belt. Trop Med Int Health 2019; 24:143-154. [PMID: 30461138 PMCID: PMC7380001 DOI: 10.1111/tmi.13185] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To review the findings of studies of pharyngeal carriage of Neisseria meningitidis and related species conducted in the African meningitis belt since a previous review published in 2007. METHODS PubMed and Web of Science were searched in July 2018 using the terms 'meningococcal OR Neisseria meningitidis OR lactamica AND carriage AND Africa', with the search limited to papers published on or after 1st January 2007. We conducted a narrative review of these publications. RESULTS One hundred and thirteen papers were identified using the search terms described above, 20 of which reported new data from surveys conducted in an African meningitis belt country. These papers described 40 surveys conducted before the introduction of the group A meningococcal conjugate vaccine (MenAfriVacR ) during which 66 707 pharyngeal swabs were obtained. Carriage prevalence of N. meningitidis varied substantially by time and place, ranging from <1% to 24%. The mean pharyngeal carriage prevalence of N. meningitidis across all surveys was 4.5% [95% CI: 3.4%, 6.8%] and that of capsulated N. meningitidis was 2.8% [95% CI: 1.9%; 5.2%]. A study of households provided strong evidence for meningococcal transmission within and outside households. The introduction of MenAfriVac® led to marked reductions in carriage of the serogroup A meningococcus in Burkina Faso and Chad. CONCLUSIONS Recent studies employing standardised methods confirm the findings of older studies that carriage of N. meningitidis in the African meningitis belt is highly variable over time and place, but generally occurs with a lower prevalence and shorter duration than reported from industrialised countries.
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Affiliation(s)
| | | | | | - Kanny Diallo
- Department of BacteriologyNoguchi Memorial Research InstituteUniversity of LegonAccraLegon
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21
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Diallo K, Coulibaly MD, Rebbetts LS, Harrison OB, Lucidarme J, Gamougam K, Tekletsion YK, Bugri A, Toure A, Issaka B, Dieng M, Trotter C, Collard JM, Sow SO, Wang X, Mayer LW, Borrow R, Greenwood BM, Maiden MCJ, Manigart O. Development of a PCR algorithm to detect and characterize Neisseria meningitidis carriage isolates in the African meningitis belt. PLoS One 2018; 13:e0206453. [PMID: 30517103 PMCID: PMC6281270 DOI: 10.1371/journal.pone.0206453] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 10/12/2018] [Indexed: 12/25/2022] Open
Abstract
Improved methods for the detection and characterization of carried Neisseria meningitidis isolates are needed. We evaluated a multiplex PCR algorithm for the detection of a variety of carriage strains in the meningitis belt. To further improve the sensitivity and specificity of the existing PCR assays, primers for gel-based PCR assays (sodC, H, Z) and primers/probe for real-time quantitative PCR (qPCR) assays (porA, cnl, sodC, H, E, Z) were modified or created using Primer Express software. Optimized multiplex PCR assays were tested on 247 well-characterised carriage isolates from six countries of the African meningitis belt. The PCR algorithm developed enabled the detection of N. meningitidis species using gel-based and real-time multiplex PCR targeting porA, sodC, cnl and characterization of capsule genes through sequential multiplex PCR assays for genogroups (A, W, X, then B, C, Y and finally H, E and Z). Targeting both porA and sodC genes together allowed the detection of meningococci with a sensitivity of 96% and 89% and a specificity of 78% and 67%, for qPCR and gel-based PCR respectively. The sensitivity and specificity ranges for capsular genogrouping of N. meningitidis are 67% - 100% and 98%-100% respectively for gel-based PCR and 90%-100% and 99%-100% for qPCR. We developed a PCR algorithm that allows simple, rapid and systematic detection and characterisation of most major and minor N. meningitidis capsular groups, including uncommon capsular groups (H, E, Z).
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Affiliation(s)
- Kanny Diallo
- Centre pour le Développement des Vaccins (CVD), Bamako, Mali
- University of Oxford (Department of Zoology), Oxford, United Kingdom
| | | | - Lisa S. Rebbetts
- University of Oxford (Department of Zoology), Oxford, United Kingdom
| | - Odile B. Harrison
- University of Oxford (Department of Zoology), Oxford, United Kingdom
| | - Jay Lucidarme
- Public Health England, (PHE–Vaccine Evaluation Unit), Manchester, United Kingdom
| | - Kadidja Gamougam
- Centre de Support en Santé Internationale (CSSI), Ndjamena, Chad
| | | | - Akalifa Bugri
- Navrongo Health Research Centre (NHRC), Navrongo, Ghana
| | - Aliou Toure
- Centre pour le Développement des Vaccins (CVD), Bamako, Mali
| | - Bassira Issaka
- Centre de Recherche Médicale et Sanitaire (CERMES), Niamey, Niger
| | - Marietou Dieng
- Institut de Recherche pour le Développement (IRD), Dakar, Senegal
| | - Caroline Trotter
- University of Cambridge (Disease Dynamics Unit -Department of Veterinary Medicine), Cambridge, United Kingdom
| | | | - Samba O. Sow
- Centre pour le Développement des Vaccins (CVD), Bamako, Mali
| | - Xin Wang
- Centers for Disease Control and Prevention, Division of Bacterial Diseases, Atlanta, United States of America
| | - Leonard W. Mayer
- Centers for Disease Control and Prevention, Division of Bacterial Diseases, Atlanta, United States of America
| | - Ray Borrow
- Public Health England, (PHE–Vaccine Evaluation Unit), Manchester, United Kingdom
| | - Brian M. Greenwood
- London School of Hygiene and Tropical Medicine (LSHTM), London, United Kingdom
| | | | - Olivier Manigart
- London School of Hygiene and Tropical Medicine (LSHTM), London, United Kingdom
- * E-mail:
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22
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Retchless AC, Congo-Ouédraogo M, Kambiré D, Vuong J, Chen A, Hu F, Ba AK, Ouédraogo AS, Hema-Ouangraoua S, Patel JC, Traoré RO, Sangaré L, Wang X. Molecular characterization of invasive meningococcal isolates in Burkina Faso as the relative importance of serogroups X and W increases, 2008-2012. BMC Infect Dis 2018; 18:337. [PMID: 30021533 PMCID: PMC6052536 DOI: 10.1186/s12879-018-3247-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 07/10/2018] [Indexed: 12/30/2022] Open
Abstract
Background Neisseria meningitidis serogroup A disease in Burkina Faso has greatly decreased following introduction of a meningococcal A conjugate vaccine in 2010, yet other serogroups continue to pose a risk of life-threatening disease. Capsule switching among epidemic-associated serogroup A N. meningitidis strains could allow these lineages to persist despite vaccination. The introduction of new strains at the national or sub-national levels could affect the epidemiology of disease. Methods Isolates collected from invasive meningococcal disease in Burkina Faso between 2008 and 2012 were characterized by serogrouping and molecular typing. Genome sequences from a subset of isolates were used to infer phylogenetic relationships. Results The ST-5 clonal complex (CC5) was identified only among serogroup A isolates, which were rare after 2010. CC181 and CC11 were the most common clonal complexes after 2010, having serogroup X and W isolates, respectively. Whole-genome phylogenetic analysis showed that the CC181 isolates collected during and after the epidemic of 2010 formed a single clade that was closely related to isolates collected in Niger during 2005 and Burkina Faso during 2007. Geographic population structure was identified among the CC181 isolates, where pairs of isolates collected from the same region of Burkina Faso within a single year had less phylogenetic diversity than the CC181 isolate collection as a whole. However, the reduction of phylogenetic diversity within a region did not extend across multiple years. Instead, CC181 isolates collected during the same year had lower than average diversity, even when collected from different regions, indicating geographic mixing of strains across years. The CC11 isolates were primarily collected during the epidemic of 2012, with sparse sampling during 2011. These isolates belong to a clade that includes previously described isolates collected in Burkina Faso, Mali, and Niger from 2011 to 2015. Similar to CC181, reduced phylogenetic diversity was observed among CC11 isolate pairs collected from the same regions during a single year. Conclusions The population of disease-associated N. meningitidis strains within Burkina Faso was highly dynamic between 2008 and 2012, reflecting both vaccine-imposed selection against serogroup A strains and potentially complex clonal waves of serogroup X and serogroup W strains. Electronic supplementary material The online version of this article (10.1186/s12879-018-3247-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Adam C Retchless
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, USA
| | | | - Dinanibè Kambiré
- Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle, Ouagadougou, Burkina Faso
| | - Jeni Vuong
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, USA
| | - Alex Chen
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, USA
| | - Fang Hu
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, USA
| | - Absetou Ky Ba
- Laboratoire National de Santé Public, Ouagadougou, Burkina Faso
| | | | | | - Jaymin C Patel
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, USA.,Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, USA
| | | | - Lassana Sangaré
- Centre Hospitalier Universitaire Yalgado Ouédraogo, Ouagadougou, Burkina Faso
| | - Xin Wang
- Meningitis and Vaccine Preventable Diseases Branch, Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, USA.
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23
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Hlozek J, Kuttel MM, Ravenscroft N. Conformations of Neisseria meningitidis serogroup A and X polysaccharides: The effects of chain length and O-acetylation. Carbohydr Res 2018; 465:44-51. [PMID: 29940397 DOI: 10.1016/j.carres.2018.06.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 06/12/2018] [Accepted: 06/12/2018] [Indexed: 11/28/2022]
Abstract
Neisseria meningitidis is a major cause of bacterial meningitis worldwide especially in Africa. The capsular polysaccharide (CPS) is the main virulence factor and the target antigen for polysaccharide and conjugate vaccines. The high burden of serogroup A disease in the Meningitis Belt of sub-Saharan Africa led to the introduction of MenAfriVac®, which has successfully reduced the number of cases of group A disease. However, several outbreaks caused by other serogroups have been reported, including those due to serogroup X. The capsular polysaccharides of serogroups A and X are both homopolymers of amino sugars (α-D-ManNAc and α-D-GlcNAc) containing phosphodiester linkages at C-6 and C-4, respectively. The similarity of the primary structures of the two polysaccharides suggests that serogroup A vaccination may provide cross-protection against serogroup X disease. Molecular dynamics simulations of a series of serogroup A and X oligosaccharides reveal that the MenA CPS behaves as a flexible random coil which becomes less conformationally defined as the length increases, whereas serogroup X forms a more stable regular helical structure. The presence of the MenX helix is supported by NMR analysis; it has four residues per turn and becomes more stable as the chain length increases. Licensed MenA vaccines are largely O-acetylated at C-3: simulations show that these O-acetyl groups are highly solvent exposed and their presence favors more extended conformations compared to the more compact conformations of MenA without O-acetylation. These findings may have implications for the design of optimal conjugate vaccines.
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Affiliation(s)
- Jason Hlozek
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, South Africa
| | - Michelle M Kuttel
- Department of Computer Science, University of Cape Town, Rondebosch, 7701, South Africa
| | - Neil Ravenscroft
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, South Africa.
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24
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Songane M. Challenges for nationwide vaccine delivery in African countries. INTERNATIONAL JOURNAL OF HEALTH ECONOMICS AND MANAGEMENT 2018; 18:197-219. [PMID: 29047019 DOI: 10.1007/s10754-017-9229-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 10/09/2017] [Indexed: 06/07/2023]
Abstract
Vaccines are very effective in providing individual and community (herd) immunity against a range of diseases. In addition to protection against a range of diseases, vaccines also have social and economic benefits. However, for vaccines to be effective, routine immunization programmes must be undertaken regularly to ensure individual and community protection. Nonetheless, in many countries in Africa, vaccination coverage is low because governments struggle to deliver vaccines to the most remote areas, thus contributing to constant outbreaks of various vaccine-preventable diseases. African governments fail to deliver vaccines to a significant percentage of the target population due to many issues in key areas such as policy setting, programme management and financing, supply chain, global vaccine market, research and development of vaccines. This review gives an overview of the causes of these issues and what is currently being done to address them. This review will discuss the role of philanthropic organisations such as the Bill and Melinda Gates Foundation and global partnerships such as the global alliance for vaccines and immunizations in the development, purchase and delivery of vaccines.
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Affiliation(s)
- Mario Songane
- McGill Life Sciences Complex, McGill University, 3649 Promenade Sir-William-Osler, Montreal, H3G 0B1, Canada.
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25
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Acquisition of virulence genes by a carrier strain gave rise to the ongoing epidemics of meningococcal disease in West Africa. Proc Natl Acad Sci U S A 2018; 115:5510-5515. [PMID: 29735685 PMCID: PMC6003489 DOI: 10.1073/pnas.1802298115] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Historically, Neisseria meningitidis serogroup A strains have caused large epidemics of meningitis across sub-Saharan Africa. Following mass vaccination from 2010, serogroup A outbreaks have been mostly eliminated. Starting in 2013 however, yearly epidemics of a previously unknown serogroup C strain have led to tens of thousands of cases in Nigeria and Niger. We show how this new strain evolved from a benign ancestor through the acquisition of virulence genes encoding the serogroup C capsule and a phage linked to invasiveness, illustrating that minor genetic changes in a microbe can have major public health consequences. Our reconstruction of the spatiotemporal outbreak dynamics in the Niger–Nigeria border region suggests direct epidemiological consequences of contrasting outbreak responses in the two countries. In the African meningitis belt, a region of sub-Saharan Africa comprising 22 countries from Senegal in the west to Ethiopia in the east, large epidemics of serogroup A meningococcal meningitis have occurred periodically. After gradual introduction from 2010 of mass vaccination with a monovalent meningococcal A conjugate vaccine, serogroup A epidemics have been eliminated. Starting in 2013, the northwestern part of Nigeria has been affected by yearly outbreaks of meningitis caused by a novel strain of serogroup C Neisseria meningitidis (NmC). In 2015, the strain spread to the neighboring country Niger, where it caused a severe epidemic. Following a relative calm in 2016, the largest ever recorded epidemic of NmC broke out in Nigeria in 2017. Here, we describe the recent evolution of this new outbreak strain and show how the acquisition of capsule genes and virulence factors by a strain previously circulating asymptomatically in the African population led to the emergence of a virulent pathogen. This study illustrates the power of long-read whole-genome sequencing, combined with Illumina sequencing, for high-resolution epidemiological investigations.
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26
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Balmer P, Burman C, Serra L, York LJ. Impact of meningococcal vaccination on carriage and disease transmission: A review of the literature. Hum Vaccin Immunother 2018; 14:1118-1130. [PMID: 29565712 PMCID: PMC5989891 DOI: 10.1080/21645515.2018.1454570] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 03/06/2018] [Accepted: 03/15/2018] [Indexed: 12/28/2022] Open
Abstract
Colonization of the human nasopharyngeal tract by the bacterium Neisseria meningitidis is usually asymptomatic, but life-threatening meningococcal disease with a clinical presentation of meningitis, septicemia, or more rarely, gastrointestinal symptoms, can develop. Invasive meningococcal disease (IMD) can be fatal within 24 hours, but IMD is vaccine-preventable. Vaccines used to protect against IMD caused by 5 of the 6 most common serogroups (A, B, C, W, and Y) may also influence carriage prevalence in vaccinated individuals. Lower carriage among vaccinated people may reduce transmission to nonvaccinated individuals to provide herd protection against IMD. This article reviews observational and clinical studies examining effects of vaccination on N. meningitidis carriage prevalence in the context of mass vaccination campaigns and routine immunization programs. Challenges associated with carriage studies are presented alongside considerations for design of future studies to assess the impact of vaccination on carriage.
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Affiliation(s)
- Paul Balmer
- Medical Development, Scientific & Clinical Affairs, Pfizer Vaccines, Pfizer Inc, Collegeville, PA, USA
| | - Cynthia Burman
- Medical Development, Scientific & Clinical Affairs, Pfizer Vaccines, Pfizer Inc, Collegeville, PA, USA
| | - Lidia Serra
- Medical Development, Scientific & Clinical Affairs, Pfizer Vaccines, Pfizer Inc, Collegeville, PA, USA
| | - Laura J. York
- Medical Development, Scientific & Clinical Affairs, Pfizer Vaccines, Pfizer Inc, Collegeville, PA, USA
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27
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Meyer SA, Kristiansen PA. Household transmission of Neisseria meningitidis in the meningitis belt. LANCET GLOBAL HEALTH 2018; 4:e885-e886. [PMID: 27855859 PMCID: PMC5776745 DOI: 10.1016/s2214-109x(16)30292-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 10/25/2016] [Indexed: 12/23/2022]
Affiliation(s)
- Sarah A Meyer
- Meningitis and Vaccine Preventable Diseases Branch, US Centers for Disease Control and Prevention, Atlanta, GA 30329, USA.
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28
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Rubilar PS, Barra GN, Gabastou JM, Alarcón P, Araya P, Hormazábal JC, Fernandez J. Increase of Neisseria meningitidis W:cc11 invasive disease in Chile has no correlation with carriage in adolescents. PLoS One 2018; 13:e0193572. [PMID: 29518095 PMCID: PMC5843251 DOI: 10.1371/journal.pone.0193572] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 02/14/2018] [Indexed: 12/15/2022] Open
Abstract
Neisseria meningitidis is a human exclusive pathogen that can lead to invasive meningococcal disease or may be carried in the upper respiratory tract without symptoms. The relationship between carriage and disease remains poorly understood but it is widely accepted that decreasing carriage by immunization should lead to a reduction of invasive cases. Latin America has experienced an increased incidence of serogroup W invasive cases of Neisseria meningitidis in the last decade. Specifically in Chile, despite low total incidence of invasive cases, serogroup W has become predominant since 2011 and has been associated with elevated mortality. Expecting to gain insight into the epidemiology of this disease, this study has used molecular typing schemes to compare Neisseria meningitidis isolates causing invasive disease with those isolates collected from adolescent carriers during the same period in Chile. A lower carriage of the serogroup W clonal complex ST-11/ET37 than expected was found; whereas, the same clonal complex accounted for 66% of total invasive meningococcal disease cases in the country that year. A high diversity of PorA variable regions and fHbp peptides was also ascertained in the carrier isolates compared to the invasive ones. According to the results shown here, the elevated number of serogroup W invasive cases in our country cannot be explained by a rise of carriage of pathogenic isolates. Overall, this study supports the idea that some strains, as W:cc11 found in Chile, possess an enhanced virulence to invade the host. Notwithstanding hypervirulence, this strain has not caused an epidemic in Chile. Finally, as genetic transfer occurs often, close surveillance of Neisseria meningitidis strains causing disease, and particularly hypervirulent W:cc11, should be kept as a priority in our country, in order to prepare the best response to face genetic changes that could lead to enhanced fitness of this pathogen.
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Affiliation(s)
- Paulina S. Rubilar
- Sub-Department of Molecular Genetics, Biomedical Department, Public Health Institute, Santiago, Chile
- Pan American Health Organization/ World Health Organization, Washington, D.C., United States of America
| | - Gisselle N. Barra
- Sub-Department of Molecular Genetics, Biomedical Department, Public Health Institute, Santiago, Chile
| | - Jean-Marc Gabastou
- Pan American Health Organization/ World Health Organization, Washington, D.C., United States of America
| | - Pedro Alarcón
- Bacteriology section, Infectious Diseases Sub-Department, Biomedical Department, Public Health Institute, Santiago, Chile
| | - Pamela Araya
- Bacteriology section, Infectious Diseases Sub-Department, Biomedical Department, Public Health Institute, Santiago, Chile
| | - Juan C. Hormazábal
- Infectious diseases sub-Department, Biomedical laboratory department, Public Health Institute, Santiago, Chile
| | - Jorge Fernandez
- Sub-Department of Molecular Genetics, Biomedical Department, Public Health Institute, Santiago, Chile
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29
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Household transmission of Neisseria meningitidis in the African meningitis belt: a longitudinal cohort study. LANCET GLOBAL HEALTH 2018; 4:e989-e995. [PMID: 27855873 DOI: 10.1016/s2214-109x(16)30244-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 07/28/2016] [Accepted: 09/23/2016] [Indexed: 01/25/2023]
Abstract
BACKGROUND Information on transmission of meningococcal infection in the African meningitis belt is scarce. We aimed to describe transmission patterns of Neisseria meningitidis (meningococcus) in households in the African meningitis belt. METHODS Cross-sectional carriage surveys were done in seven African meningitis belt countries (Chad, Ethiopia, Ghana, Mali, Niger, Nigeria, and Senegal) between Aug 1, 2010, and Oct 15, 2012. Meningococcal carriers identified in these surveys and all available people in their households were recruited into this longitudinal cohort study. We took pharyngeal swabs at first visit and took further swabs twice a month for 2 months and then monthly for a further 4 months. We used conventional bacteriological and molecular techniques to identify and characterise meningococci. We estimated the rates of carriage acquisition and recovery using a multi-state Markov model. FINDINGS Meningococci were isolated from 241 (25%) of 980 members of 133 households in which a carrier had been identified in the cross-sectional survey or at the first household visit. Carriage was detected subsequently in another household member who was not an index carrier in 75 households. Transmission within a household, suggested by detection of a further carrier with the same strain as the index carrier, was found in 52 of these 75 households. Children younger than 5 years were the group that most frequently acquired carriage from other household members. The overall individual acquisition rate was 2·4% (95% CI 1·6-4·0) per month, varying by age and household carriage status. The mean duration of carriage was 3·4 months (95% CI 2·7-4·4). INTERPRETATION In the African meningitis belt, transmission of meningococci within households is important, particularly for young children, and periods of carriage are usually of short duration. FUNDING Bill & Melinda Gates Foundation, Wellcome Trust.
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30
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Abstract
The introduction of a serogroup A meningococcal conjugate vaccine in the African meningitis belt has been a remarkable success. Meningitis due to the serogroup A meningococcus, previously responsible for most epidemics, has fallen by 99% in vaccinated countries. Success must, however, not distract from the continuing burden of meningitis in this region of Africa. The number of all meningitis epidemics at health district level has fallen by 60% following vaccination, but epidemics due to other meningococcal serogroups continue and may be increasing. The introduction of low cost multivalent conjugate vaccines must be given high public health priority.
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Affiliation(s)
- James M Stuart
- a London School of Hygiene and Tropical Medicine , London , UK
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31
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Basta NE, Berthe A, Keita M, Onwuchekwa U, Tamboura B, Traore A, Hassan-King M, Manigart O, Nascimento M, Stuart JM, Trotter C, Blake J, Carr AD, Gray SJ, Newbold LS, Deng Y, Wolfson J, Halloran ME, Greenwood B, Borrow R, Sow SO. Meningococcal carriage within households in the African meningitis belt: A longitudinal pilot study. J Infect 2017; 76:140-148. [PMID: 29197599 PMCID: PMC5790055 DOI: 10.1016/j.jinf.2017.11.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 11/22/2017] [Indexed: 10/29/2022]
Abstract
OBJECTIVES Carriers of Neisseria meningitidis are a key source of transmission. In the African meningitis belt, where risk of meningococcal disease is highest, a greater understanding of meningococcal carriage dynamics is needed. METHODS We randomly selected an age-stratified sample of 400 residents from 116 households in Bamako, Mali, and collected pharyngeal swabs in May 2010. A month later, we enrolled all 202 residents of 20 of these households (6 with known carriers) and collected swabs monthly for 6 months prior to MenAfriVac vaccine introduction and returned 10 months later to collect swabs monthly for 3 months. We used standard bacteriological methods to identify N. meningitidis carriers and fit hidden Markov models to assess acquisition and clearance overall and by sex and age. RESULTS During the cross-sectional study 5.0% of individuals (20/400) were carriers. During the longitudinal study, 73 carriage events were identified from 1422 swabs analyzed, and 16.3% of individuals (33/202) were identified as carriers at least once. The majority of isolates were non-groupable; no serogroup A carriers were identified. CONCLUSIONS Our results suggest that the duration of carriage with any N. meningitidis averages 2.9 months and that males and children acquire and lose carriage more frequently in an urban setting in Mali. Our study informed the design of a larger study implemented in seven countries of the African meningitis belt.
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Affiliation(s)
- Nicole E Basta
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota 55454, USA.
| | - Abdoulaye Berthe
- Centre pour les Vaccins en Developpement-Mali, Centre National d'Appui a la lutte contre la Maladie (CNAM) Ministère de la Santé, Ex-Institut Marchoux, BP 251, Bamako, Mali
| | - Mahamadou Keita
- Centre pour les Vaccins en Developpement-Mali, Centre National d'Appui a la lutte contre la Maladie (CNAM) Ministère de la Santé, Ex-Institut Marchoux, BP 251, Bamako, Mali
| | - Uma Onwuchekwa
- Centre pour les Vaccins en Developpement-Mali, Centre National d'Appui a la lutte contre la Maladie (CNAM) Ministère de la Santé, Ex-Institut Marchoux, BP 251, Bamako, Mali
| | - Boubou Tamboura
- Centre pour les Vaccins en Developpement-Mali, Centre National d'Appui a la lutte contre la Maladie (CNAM) Ministère de la Santé, Ex-Institut Marchoux, BP 251, Bamako, Mali
| | - Awa Traore
- Centre pour les Vaccins en Developpement-Mali, Centre National d'Appui a la lutte contre la Maladie (CNAM) Ministère de la Santé, Ex-Institut Marchoux, BP 251, Bamako, Mali
| | - Musa Hassan-King
- London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Olivier Manigart
- Centre pour les Vaccins en Developpement-Mali, Centre National d'Appui a la lutte contre la Maladie (CNAM) Ministère de la Santé, Ex-Institut Marchoux, BP 251, Bamako, Mali; London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Maria Nascimento
- London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - James M Stuart
- London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Caroline Trotter
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
| | - Jayne Blake
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester, M13 9WL, United Kingdom
| | - Anthony D Carr
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester, M13 9WL, United Kingdom
| | - Stephen J Gray
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester, M13 9WL, United Kingdom
| | - Lynne S Newbold
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester, M13 9WL, United Kingdom
| | - Yangqing Deng
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, Minnesota 55454, USA
| | - Julian Wolfson
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, Minnesota 55454, USA
| | - M Elizabeth Halloran
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA; Department of Biostatistics, University of Washington, Seattle, Washington 98195, USA
| | - Brian Greenwood
- London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Ray Borrow
- Meningococcal Reference Unit, Public Health England, Manchester Royal Infirmary, Manchester, M13 9WL, United Kingdom
| | - Samba O Sow
- Centre pour les Vaccins en Developpement-Mali, Centre National d'Appui a la lutte contre la Maladie (CNAM) Ministère de la Santé, Ex-Institut Marchoux, BP 251, Bamako, Mali
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Cost-effectiveness Comparison of Monovalent C Versus Quadrivalent ACWY Meningococcal Conjugate Vaccination in Canada. Pediatr Infect Dis J 2017; 36:e203-e207. [PMID: 28027288 DOI: 10.1097/inf.0000000000001512] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND In Quebec, 1 dose of monovalent C meningococcal conjugate vaccine (Men-C-Con) is offered at 12 months of age and a booster dose in grade 9 (14-15 years of age). In other Canadian provinces, a quadrivalent vaccine against serogroups ACWY (Men-4-Con) is increasingly used for adolescents. An economic analysis was performed to assess the value of a switch from Men-C-Con to Men-4-Con. METHODS A compartmental static simulation model was developed to assess the burden of invasive meningococcal disease due to serogroups AWY (AWY-IMD) in a cohort of 100,000 persons with different vaccination programs. Univariate and multivariate sensitivity analyses were performed, including variation in vaccine price difference ($12; range: $0-$20), AWY-IMD rate (0.08/100,000 to 0.28/100,000 person-years), level of herd immunity generated by adolescent vaccination (from zero to disease elimination) and discounting rate (0%, 3% or 6%). RESULTS In the low AWY-IMD rate base scenario, replacing Men-C-Con by Men-4-Con for adolescents would reduce disease burden by 16% (no herd effect) to 58% (moderate herd effect), with an incremental cost-effectiveness ratios between $445,000 per quality-adjusted life-year (QALY) and $167,000/QALY in a societal perspective. In the high AWY-IMD rate scenario, incremental cost-effectiveness ratio would be in the range of $97,000/QALY to $19,000/QALY. CONCLUSION Based on the epidemiologic conditions in Quebec and in most other Canadian provinces, the benefits of Men-4-Con in reducing the burden of disease would be low for a high cost. The switch would, however, be more economically attractive with a much higher incidence rate (as in a few provinces) or with a reduced vaccine price in conditions assuming a moderate to high herd effect.
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Gianchecchi E, Piccini G, Torelli A, Rappuoli R, Montomoli E. An unwanted guest:Neisseria meningitidis– carriage, risk for invasive disease and the impact of vaccination with insight on Italy incidence. Expert Rev Anti Infect Ther 2017; 15:689-701. [DOI: 10.1080/14787210.2017.1333422] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - Giulia Piccini
- VisMederi Srl, Siena, Italy
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Alessandro Torelli
- VisMederi Srl, Siena, Italy
- Department of Life Sciences, University of Siena, Siena, Italy
| | | | - Emanuele Montomoli
- VisMederi Srl, Siena, Italy
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
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Vipond C, Swann CJ, Dougall TW, Rigsby P, Gao F, Beresford NJ, Bolgiano B. Evaluation of candidate international standards for meningococcal serogroups A and X polysaccharide. Biologicals 2017; 47:33-45. [DOI: 10.1016/j.biologicals.2017.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 03/03/2017] [Indexed: 12/29/2022] Open
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Abstract
The protective effect of meningococcal vaccines targeting disease causing serogroups exemplified by the introduction of MenAfriVac™ in Africa, is well established and documented in large population-based studies. Due to the emergence of other meningococcal disease causing serogroups, novel vaccine formulations are needed. There is a high potential for novel nanotechnology-based meningococcal vaccine formulations that can provide wider vaccine coverage. The proposed meningococcal vaccine formulation contains spherical shaped micro and nanoparticles that are biological mimics of Niesseria meningitidis, therefore present to immune system as invader and elicit robust immune responses. Vaccine nanoparticles encapsulate meningococcal CPS polymers in a biodegradable material that slowly release antigens, therefore enhance antigen presentation by exerting antigen depot effect. The antigenicity of meningococcal vaccine delivered in nanoparticles is significantly higher when compared to vaccine delivered in solution. Preclinical studies are required to assess the immunogenicity of novel vaccine formulations. Therefore, implementing various in-vitro human immune cell-based assays that mimic in-vivo interactions, would provide good insight on optimal antigen dose, effective antigen presentation, facilitate screening of various vaccine and adjuvant combinations and predict in-vivo immunogenicity. This rapid approach is cost-effective and provides data required for the preclinical immunogenicity assessment of novel meningococcal vaccine formulations.
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Affiliation(s)
- Susu M Zughaier
- a Laboratory of Bacterial Pathogenesis , Department of Veterans Affairs Medical Center , Decatur , GA , USA.,b Department of Microbiology and Immunology , Emory University School of Medicine , Atlanta , GA , USA
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Ganesh K, Allam M, Wolter N, Bratcher HB, Harrison OB, Lucidarme J, Borrow R, de Gouveia L, Meiring S, Birkhead M, Maiden MCJ, von Gottberg A, du Plessis M. Molecular characterization of invasive capsule null Neisseria meningitidis in South Africa. BMC Microbiol 2017; 17:40. [PMID: 28222677 PMCID: PMC5320719 DOI: 10.1186/s12866-017-0942-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 01/31/2017] [Indexed: 12/15/2022] Open
Abstract
Background The meningococcal capsule is an important virulence determinant. Unencapsulated meningococci lacking capsule biosynthesis genes and containing the capsule null locus (cnl) are predominantly non-pathogenic. Rare cases of invasive meningococcal disease caused by cnl isolates belonging to sequence types (ST) and clonal complexes (cc) ST-845 (cc845), ST-198 (cc198), ST-192 (cc192) and ST-53 (cc53) have been documented. The clinical significance of these isolates however remains unclear. We identified four invasive cnl meningococci through laboratory-based surveillance in South Africa from 2003 through 2013, which we aimed to characterize using whole genome data. Results One isolate [NG: P1.7-2,30: F1-2: ST-53 (cc53)] contained cnl allele 12, and caused empyema in an adult male with bronchiectasis from tuberculosis, diabetes mellitus and a smoking history. Three isolates were NG: P1.18-11,42-2: FΔ: ST-192 (cc192) and contained cnl allele 2. One patient was an adolescent male with meningitis. The remaining two isolates were from recurrent disease episodes (8 months apart) in a male child with deficiency of the sixth complement component, and with the exception of two single nucleotide polymorphisms, contained identical core genomes. The ST-53 (cc53) isolate possessed alleles for NHBA peptide 191 and fHbp variant 2; whilst the ST-192 (cc192) isolates contained NHBA peptide 704 and fHbp variant 3. All four isolates lacked nadA. Comparison of the South African genomes to 61 additional cnl genomes on the PubMLST Neisseria database (http://pubmlst.org/neisseria/), determined that most putative virulence genes could be found in both invasive and carriage phenotypes. Conclusions Although rare, invasive disease by cnl meningococci may be associated with host immunodeficiency and such patients may benefit from protein-based meningococcal vaccines. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-0942-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Karistha Ganesh
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa. .,School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Mushal Allam
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Nicole Wolter
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa.,School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | | | | | - Jay Lucidarme
- Meningococcal Reference Unit, Public Health England, Manchester Medical Microbiology Partnership, Manchester Royal Infirmary, Manchester, UK
| | - Ray Borrow
- Meningococcal Reference Unit, Public Health England, Manchester Medical Microbiology Partnership, Manchester Royal Infirmary, Manchester, UK
| | - Linda de Gouveia
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Susan Meiring
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Monica Birkhead
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | | | - Anne von Gottberg
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa.,School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Mignon du Plessis
- National Institute for Communicable Diseases (NICD), A division of the National Health Laboratory Service (NHLS), Johannesburg, South Africa.,School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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Abstract
The incidence of meningococcal disease is at an historic low in the United States, but prevention remains a priority because of the devastating outcomes and risk for outbreaks. Available vaccines are recommended routinely for persons at increased risk for disease to protect against all major serogroups of Neisseria meningitidis circulating in the United States. Although vaccination has virtually eliminated serogroup A meningococcal outbreaks from the Meningitis Belt of Africa and reduced the incidence of serogroup C disease worldwide, eradication of N meningitidis will unlikely be achieved by currently available vaccines because of the continued carriage and transmission of nonencapsulated organisms.
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Affiliation(s)
- Amanda Cohn
- Immunization Services Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - Jessica MacNeil
- Bacterial Diseases Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
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Diallo A, Sow SO, Idoko OT, Hirve S, Findlow H, Preziosi MP, Elie C, Kulkarni PS, Parulekar V, Diarra B, Cheick Haidara F, Diallo F, Tapia M, Akinsola AK, Adegbola RA, Bavdekar A, Juvekar S, Chaumont J, Martellet L, Marchetti E, LaForce MF, Plikaytis BD, Enwere GC, Tang Y, Borrow R, Carlone G, Viviani S. Antibody Persistence at 1 and 4 Years Following a Single Dose of MenAfriVac or Quadrivalent Polysaccharide Vaccine in Healthy Subjects Aged 2-29 Years. Clin Infect Dis 2016; 61 Suppl 5:S521-30. [PMID: 26553684 PMCID: PMC4639491 DOI: 10.1093/cid/civ518] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Mass vaccination campaigns of the population aged 1-29 years with 1 dose of group A meningococcal (MenA) conjugate vaccine (PsA-TT, MenAfriVac) in African meningitis belt countries has resulted in the near-disappearance of MenA. The vaccine was tested in clinical trials in Africa and in India and found to be safe and highly immunogenic compared with the group A component of the licensed quadrivalent polysaccharide vaccine (PsACWY). Antibody persistence in Africa and in India was investigated. METHODS A total of 900 subjects aged 2-29 years were followed up for 4 years in Senegal, Mali, and The Gambia (study A). A total of 340 subjects aged 2-10 years were followed up for 1 year in India (study B). In study A, subjects were randomized in a 2:1 ratio, and in study B a 1:1 ratio to receive either PsA-TT or PsACWY. Immunogenicity was evaluated by measuring MenA serum bactericidal antibody (SBA) with rabbit complement and by a group A-specific immunoglobulin G (IgG) enzyme-linked immunosorbent assay. RESULTS In both studies, substantial SBA decay was observed at 6 months postvaccination in both vaccine groups, although more marked in the PsACWY group. At 1 year and 4 years (only for study A) postvaccination, SBA titers were relatively sustained in the PsA-TT group, whereas a slight increasing trend, more pronounced among the youngest, was observed in the participants aged <18 years in the PsACWY groups. The SBA titers were significantly higher in the PsA-TT group than in the PsACWY group at any time point, and the majority of subjects in the PsA-TT group had SBA titers ≥128 and group A-specific IgG concentrations ≥2 µg/mL at any point in time in both the African and Indian study populations. CONCLUSIONS Four years after vaccination with a single dose of PsA-TT vaccine in Africa, most subjects are considered protected from MenA disease. CLINICAL TRIALS REGISTRATION PsA-TT-003 (ISRCTN87739946); PsA-TT-003a (ISRCTN46335400).
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Affiliation(s)
- Aldiouma Diallo
- Institut de Recherche pour le Développement, Niakhar, Sénégal
| | - Samba O Sow
- Centre pour le Développement des Vaccins, Ministère de la Santé, Bamako, Mali
| | | | - Siddhivinayak Hirve
- Shirdi Sai Baba Hospital, Vadu/King Edward Memorial Hospital and Research Centre, Pune, India
| | - Helen Findlow
- Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom
| | - Marie-Pierre Preziosi
- Meningitis Vaccine Project, PATH, Ferney-Voltaire, France Meningitis Vaccine Project, Department of Immunization, Vaccines and Biologicals, World Health Organization, Geneva, Switzerland
| | - Cheryl Elie
- Centers for Disease Control and Prevention, Atlanta, Georgia
| | | | | | - Bou Diarra
- Institut de Recherche pour le Développement, Niakhar, Sénégal
| | | | - Fatoumata Diallo
- Centre pour le Développement des Vaccins, Ministère de la Santé, Bamako, Mali
| | - Milagritos Tapia
- Department of Pediatrics, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore
| | | | | | - Ashish Bavdekar
- Shirdi Sai Baba Hospital, Vadu/King Edward Memorial Hospital and Research Centre, Pune, India
| | - Sanjay Juvekar
- Shirdi Sai Baba Hospital, Vadu/King Edward Memorial Hospital and Research Centre, Pune, India
| | - Julie Chaumont
- Meningitis Vaccine Project, PATH, Ferney-Voltaire, France
| | | | | | | | | | | | - Yuxiao Tang
- Meningitis Vaccine Project, PATH, Seattle, Washington
| | - Ray Borrow
- Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom
| | - George Carlone
- Centers for Disease Control and Prevention, Atlanta, Georgia
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Basta NE, Borrow R, Berthe A, Dembélé ATE, Onwuchekwa U, Townsend K, Boukary RM, Mabey L, Findlow H, Bai X, Sow SO. Population-Level Persistence of Immunity 2 Years After the PsA-TT Mass-Vaccination Campaign in Mali. Clin Infect Dis 2016; 61 Suppl 5:S547-53. [PMID: 26553687 PMCID: PMC4639504 DOI: 10.1093/cid/civ602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Background. In 2010, Africa's first preventive meningococcal mass vaccination campaign was launched using a newly developed Neisseria meningitidis group A (NmA) polysaccharide–tetanus toxoid conjugate vaccine, PsA-TT (MenAfriVac), designed specifically for the meningitis belt. Given PsA-TT's recent introduction, the duration of protection against meningococcal group A is unknown. Methods. We conducted a household-based, age-stratified seroprevalence survey in Bamako, Mali, in 2012, 2 years after the vaccination campaign targeted all 1- to 29-year-olds. Randomly selected participants who had been eligible for PsA-TT provided a blood sample and responded to a questionnaire. Sera were analyzed to assess NmA-specific serum bactericidal antibody titers using rabbit complement (rSBA) and NmA-specific immunoglobulin G (IgG) by enzyme-linked immunosorbent assay. The proportion of participants putatively protected and the age group- and sex-specific rSBA geometric mean titers (GMTs) and IgG geometric mean concentrations (GMCs) were determined. Results. Two years postvaccination, nearly all of the 800 participants (99.0%; 95% confidence interval [CI], 98.3%–99.7%) maintained NmA-specific rSBA titers ≥8, the accepted threshold for protection; 98.6% (95% CI, 97.8%–99.4%) had titers ≥128, and 89.5% (95% CI, 87.4%–91.6%) had titers ≥1024. The rSBA GMTs were significantly higher in females than in males aged <18 years at vaccination (P < .0001). NmA-specific IgG levels ≥2 µg/mL were found in 88.5% (95% CI, 86.3%–90.7%) of participants. Conclusions. Two years after PsA-TT introduction, a very high proportion of the population targeted for vaccination maintains high antibody titers against NmA. Assessing the duration of protection provided by PsA-TT is a priority for implementing evidence-based vaccination strategies. Representative, population-based seroprevalence studies complement clinical trials and provide this key evidence.
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Affiliation(s)
- Nicole E Basta
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis Fogarty International Center, National Institutes of Health, Bethesda, Maryland
| | - Ray Borrow
- Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom
| | - Abdoulaye Berthe
- Centre pour le Développement des Vaccins, Ministère de la Santé, Bamako, Mali
| | | | - Uma Onwuchekwa
- Centre pour le Développement des Vaccins, Ministère de la Santé, Bamako, Mali
| | - Kelly Townsend
- Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom
| | - Rahamatou M Boukary
- Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom
| | - Lesley Mabey
- Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom
| | - Helen Findlow
- Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom
| | - Xilian Bai
- Vaccine Evaluation Unit, Public Health England, Manchester Royal Infirmary, United Kingdom
| | - Samba O Sow
- Centre pour le Développement des Vaccins, Ministère de la Santé, Bamako, Mali
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Piccini G, Torelli A, Gianchecchi E, Piccirella S, Montomoli E. FightingNeisseria meningitidis: past and current vaccination strategies. Expert Rev Vaccines 2016; 15:1393-1407. [DOI: 10.1080/14760584.2016.1187068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Diallo K, Trotter C, Timbine Y, Tamboura B, Sow SO, Issaka B, Dano ID, Collard JM, Dieng M, Diallo A, Mihret A, Ali OA, Aseffa A, Quaye SL, Bugri A, Osei I, Gamougam K, Mbainadji L, Daugla DM, Gadzama G, Sambo ZB, Omotara BA, Bennett JS, Rebbetts LS, Watkins ER, Nascimento M, Woukeu A, Manigart O, Borrow R, Stuart JM, Greenwood BM, Maiden MCJ. Pharyngeal carriage of Neisseria species in the African meningitis belt. J Infect 2016; 72:667-677. [PMID: 27018131 PMCID: PMC4879866 DOI: 10.1016/j.jinf.2016.03.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/14/2016] [Accepted: 03/16/2016] [Indexed: 12/29/2022]
Abstract
Objectives Neisseria meningitidis, together with the non-pathogenic Neisseria species (NPNs), are members of the complex microbiota of the human pharynx. This paper investigates the influence of NPNs on the epidemiology of meningococcal infection. Methods Neisseria isolates were collected during 18 surveys conducted in six countries in the African meningitis belt between 2010 and 2012 and characterized at the rplF locus to determine species and at the variable region of the fetA antigen gene. Prevalence and risk factors for carriage were analyzed. Results A total of 4694 isolates of Neisseria were obtained from 46,034 pharyngeal swabs, a carriage prevalence of 10.2% (95% CI, 9.8–10.5). Five Neisseria species were identified, the most prevalent NPN being Neisseria lactamica. Six hundred and thirty-six combinations of rplF/fetA_VR alleles were identified, each defined as a Neisseria strain type. There was an inverse relationship between carriage of N. meningitidis and of NPNs by age group, gender and season, whereas carriage of both N. meningitidis and NPNs was negatively associated with a recent history of meningococcal vaccination. Conclusion Variations in the prevalence of NPNs by time, place and genetic type may contribute to the particular epidemiology of meningococcal disease in the African meningitis belt. A prevalence of 10.2% of Neisseria infection was observed during the study. Five Neisseria species were identified in nasopharyngeal samples. High level of genetic diversity was observed in carried isolates. Inverse relationship between carriage of Neisseria meningitidis and non-pathogenic Neisseria.
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Affiliation(s)
- Kanny Diallo
- Centre pour les Vaccins en Développement, Bamako, Mali; Department of Zoology, University of Oxford, Oxford, UK.
| | - Caroline Trotter
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | | | | | - Samba O Sow
- Centre pour les Vaccins en Développement, Bamako, Mali
| | - Bassira Issaka
- Centre de Recherche Médicale et Sanitaire, Niamey, Niger
| | - Ibrahim D Dano
- Centre de Recherche Médicale et Sanitaire, Niamey, Niger
| | | | - Marietou Dieng
- Institut de Recherche pour le Développement, Dakar, Senegal
| | | | - Adane Mihret
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Oumer A Ali
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Abraham Aseffa
- Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | | | | | - Isaac Osei
- Navrongo Health Research Centre, Navrongo, Ghana
| | | | | | | | | | | | | | | | | | | | | | - Arouna Woukeu
- London School of Hygiene & Tropical Medicine, London, UK
| | | | - Ray Borrow
- Vaccine Evaluation Unit, Public Health England, Manchester, UK
| | - James M Stuart
- London School of Hygiene & Tropical Medicine, London, UK
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Baxter R, Keshavan P, Welsch JA, Han L, Smolenov I. Persistence of the immune response after MenACWY-CRM vaccination and response to a booster dose, in adolescents, children and infants. Hum Vaccin Immunother 2016; 12:1300-10. [PMID: 26829877 DOI: 10.1080/21645515.2015.1136040] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Persistence of bactericidal antibodies following vaccination is extremely important for protection against invasive meningococcal disease, given the epidemiology and rapid progression of meningococcal infection. We present an analysis of antibody persistence and booster response to MenACWY-CRM, in adolescents, children and infants, from 7 clinical studies. Immunogenicity was assessed using the serum bactericidal assay with both human and rabbit complement. Post-vaccination hSBA titers were high, with an age- and serogroup-specific decline in titers up to 1 y and stable levels up to 5 y The waning of hSBA titers over time was more pronounced among infants and toddlers and the greatest for serogroup A. However, rSBA titers against serogroup A were consistently higher and showed little decline over time, suggesting that protection against this serogroup may be sustained. A single booster dose of MenACWY-CRM administered at 3 to 5 y induced a robust immune response in all age groups.
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Affiliation(s)
- Roger Baxter
- a Kaiser Permanente Vaccine Study Center , Oakland , CA , USA
| | | | | | - Linda Han
- c GlaxoSmithKline LLC , Cambridge , MA , USA
| | - Igor Smolenov
- b GlaxoSmithKline B.V. , Amsterdam , The Netherlands
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Lee D, Kim EJ, Kilgore PE, Takahashi H, Ohnishi M, Tomono J, Miyamoto S, Omagari D, Kim DW, Seki M. A Novel Loop-Mediated Isothermal Amplification Assay for Serogroup Identification of Neisseria meningitidis in Cerebrospinal Fluid. Front Microbiol 2016; 6:1548. [PMID: 26793181 PMCID: PMC4709847 DOI: 10.3389/fmicb.2015.01548] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/21/2015] [Indexed: 01/01/2023] Open
Abstract
We have developed a novel Neisseria meningitidis serogroup-specific loop-mediated isothermal amplification (LAMP) assay for six of the most common meningococcal serogroups (A, B, C, W, X, and Y). The assay was evaluated using a set of 31 meningococcal LAMP assay positive cerebrospinal fluid (CSF) specimens from 1574 children with suspected meningitis identified in prospective surveillance between 1998 and 2002 in Vietnam, China, and Korea. Primer specificity was validated using 15 N. meningitidis strains (including serogroups A, B, C, E, W, X, Y, and Z) and 19 non-N. meningitidis species. The N. meningitidis serogroup LAMP detected down to ten copies and 100 colony-forming units per reaction. Twenty-nine CSF had N. meningitidis serogroup identified by LAMP compared with two CSF in which N. meningitidis serogroup was identified by culture and multi-locus sequence typing. This is the first report of a serogroup-specific identification assay for N. meningitidis using the LAMP method. Our results suggest that this assay will be a rapid, sensitive, and uniquely serogroup-specific assay with potential for application in clinical laboratories and public health surveillance systems.
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Affiliation(s)
- DoKyung Lee
- Department of Pharmacy, College of Pharmacy, Hanyang UniversityAnsan, South Korea; Institute of Pharmacological Research, Hanyang UniversityAnsan, South Korea
| | - Eun Jin Kim
- Department of Pharmacy, College of Pharmacy, Hanyang UniversityAnsan, South Korea; Institute of Pharmacological Research, Hanyang UniversityAnsan, South Korea
| | - Paul E Kilgore
- Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy & Health Sciences, Wayne State University Detroit, MI, USA
| | - Hideyuki Takahashi
- Department of Bacteriology I, National Institute of Infectious Diseases Tokyo, Japan
| | - Makoto Ohnishi
- Department of Bacteriology I, National Institute of Infectious Diseases Tokyo, Japan
| | | | | | - Daisuke Omagari
- Nihon University School of DentistryTokyo, Japan; Dental Research Center, Nihon University School of DentistryTokyo, Japan
| | - Dong Wook Kim
- Department of Pharmacy, College of Pharmacy, Hanyang UniversityAnsan, South Korea; Institute of Pharmacological Research, Hanyang UniversityAnsan, South Korea
| | - Mitsuko Seki
- Nihon University School of DentistryTokyo, Japan; Dental Research Center, Nihon University School of DentistryTokyo, Japan
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Pajon R, Lujan E, Granoff DM. A meningococcal NOMV-FHbp vaccine for Africa elicits broader serum bactericidal antibody responses against serogroup B and non-B strains than a licensed serogroup B vaccine. Vaccine 2015; 34:643-649. [PMID: 26709637 DOI: 10.1016/j.vaccine.2015.12.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 12/09/2015] [Accepted: 12/11/2015] [Indexed: 11/30/2022]
Abstract
BACKGROUND Meningococcal epidemics in Sub-Sahara caused by serogroup A strains are controlled by a group A polysaccharide conjugate vaccine. Strains with serogroups C, W and X continue to cause epidemics. Protein antigens in licensed serogroup B vaccines are shared among serogroup B and non-B strains. PURPOSE Compare serum bactericidal antibody responses elicited by an investigational native outer membrane vesicle vaccine with over-expressed Factor H binding protein (NOMV-FHbp) and a licensed serogroup B vaccine (MenB-4C) against African serogroup A, B, C, W and X strains. METHODS Human Factor H (FH) transgenic mice were immunized with NOMV-FHbp prepared from a mutant African meningococcal strain containing genetically attenuated endotoxin and a mutant sub-family B FHbp antigen with low FH binding, or with MenB-4C, which contains a recombinant sub-family B FHbp antigen that binds human FH, and three other antigens, NHba, NadA and PorA P1.4, capable of eliciting bactericidal antibody. RESULTS The NOMV-FHbp elicited serum bactericidal activity against 12 of 13 serogroup A, B, W or X strains from Africa, and four isogenic serogroup B mutants with sub-family B FHbp sequence variants. There was no activity against a serogroup B mutant with sub-family A FHbp, or two serogroup C isolates from a recent outbreak in Northern Nigeria, which were mismatched for both PorA and sub-family of the FHbp vaccine antigen. For MenB-4C, NHba was expressed by all 16 African isolates tested, FHbp sub-family B in 13, and NadA in five. However, MenB-4C elicited titers ≥ 1:10 against only one isolate, and against only two of four serogroup B mutant strains with sub-family B FHbp sequence variants. CONCLUSIONS NOMV-FHbp has greater potential to confer serogroup-independent protection in Africa than the licensed MenB-4C vaccine. However, the NOMV-FHbp vaccine will require inclusion of sub-family A FHbp for coverage against recent serogroup C strains causing outbreaks in Northern Nigeria.
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Affiliation(s)
- Rolando Pajon
- Center for Immunobiology and Vaccine Development, UCSF Benioff Children's Hospital Oakland Research Institute, Oakland, CA, USA
| | - Eduardo Lujan
- Center for Immunobiology and Vaccine Development, UCSF Benioff Children's Hospital Oakland Research Institute, Oakland, CA, USA
| | - Dan M Granoff
- Center for Immunobiology and Vaccine Development, UCSF Benioff Children's Hospital Oakland Research Institute, Oakland, CA, USA.
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Price GA, Hollander AM, Plikaytis BD, Mocca BT, Carlone G, Findlow H, Borrow R, Sow SO, Diallo A, Idoko OT, Enwere GC, Elie C, Preziosi MP, Kulkarni PS, Bash MC. Human Complement Bactericidal Responses to a Group A Meningococcal Conjugate Vaccine in Africans and Comparison to Responses Measured by 2 Other Group A Immunoassays. Clin Infect Dis 2015; 61 Suppl 5:S554-62. [DOI: 10.1093/cid/civ504] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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Kristiansen PA, Jørgensen HJ, Caugant DA. Serogroup A meningococcal conjugate vaccines in Africa. Expert Rev Vaccines 2015; 14:1441-58. [PMID: 26358167 DOI: 10.1586/14760584.2015.1084232] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Serogroup A meningococcal epidemics have been a recurrent public health problem, especially in resource-poor countries of Africa. Recently, the administration in mass vaccination campaigns of a single dose of the monovalent meningococcal conjugate vaccine, MenAfriVac, to the 1-29 year-old population of sub-Saharan Africa has prevented epidemics of meningitis caused by serogroup A Neisseria meningitidis. This strategy has also been shown to provide herd protection of the non-vaccinated population. Development of meningococcal conjugate vaccines covering other serogroups and enhanced use of the pneumococcal and Haemophilus influenzae type b conjugate vaccines must be pursued to fully control bacterial meningitis in sub-Saharan Africa.
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Affiliation(s)
- Paul A Kristiansen
- a 1 WHO Collaborating Centre for Reference and Research on Meningococci, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
| | - Hannah J Jørgensen
- a 1 WHO Collaborating Centre for Reference and Research on Meningococci, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway
| | - Dominique A Caugant
- a 1 WHO Collaborating Centre for Reference and Research on Meningococci, Norwegian Institute of Public Health, Lovisenberggata 8, 0456 Oslo, Norway.,b 2 Faculty of medicine, University of Oslo, Kirkeveien 166, 0450 Oslo, Norway
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GABUTTI G, STEFANATI A, KUHDARI P. Epidemiology of Neisseria meningitidis infections: case distribution by age and relevance of carriage. JOURNAL OF PREVENTIVE MEDICINE AND HYGIENE 2015; 56:E116-20. [PMID: 26788731 PMCID: PMC4755119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 07/29/2015] [Indexed: 11/29/2022]
Abstract
Notwithstanding different meningococcal serogroups have changed their distribution and their impact in different age classes over time, N. meningitidis' invasive diseases are a major public health issue worldwide, due to the related complications and severe sequelae. Nowadays, the highest rates of invasive disease are registered in children younger than 1 year of age, with a second lesser peak in adolescents and young adults (15-25 years of age). On the contrary, the prevalence of carriage is low in newborns and in school-age children, and increases during adolescence and young-adult age; then it decreases again in older age. N. meningitidis' infection prevalence has greatly decreased in Europe and North America thanks to the use of conjugate vaccines (MenC and MenACWY) as well as the incidence of invasive disease due to serogroup A in sub-saharian Africa after the introduction of MenAfriVac conjugate vaccine. The great success of conjugate vaccines is related not only to the direct protection from disease but also to the impact on carriage; this latter allows an indirect protection of unimmunized subjects. For these reasons, the implementation of immunization with the new generation vaccines in the age classes most impacted by disease and carriage (first year of life, adolescence and young adulthood) could permit to achieve an extraordinary decrease of the incidence of meningococcal disease.
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Affiliation(s)
- G. GABUTTI
- Correspondence: Giovanni Gabutti, c/o Dept. of Medical Sciences, via Fossato di Mortara 64b, 44121 Ferrara, Italy - Tel. +39 532 455568 - Fax 0039 532 205066 - E-mail:
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