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Hadley L, Soeters HM, Cooper LV, Fernandez K, Latt A, Bita Fouda AA, Trotter C. Modelling control strategies for pneumococcal meningitis outbreaks in the African meningitis belt. Vaccine 2024; 42:125983. [PMID: 38797628 DOI: 10.1016/j.vaccine.2024.05.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 05/29/2024]
Abstract
INTRODUCTION Pneumococcal meningitis outbreaks occur sporadically in the African meningitis belt. Outbreak control guidelines and interventions are well established for meningococcal but not pneumococcal meningitis. Mathematical modelling is a useful tool for assessing the potential impact of different pneumococcal control strategies. This work aimed to estimate the impact of reactive vaccination with pneumococcal conjugate vaccine (PCV) had it been implemented in past African meningitis belt outbreaks and assess their efficiency relative to existing routine infant immunisation with PCV. METHODS & RESULTS Using recent pneumococcal meningitis outbreaks in Burkina Faso, Chad, and Ghana as case studies, we investigated the potential impact of reactive vaccination. We calculated the number needed to vaccinate to avert one case (NNV) in each outbreak setting and over all outbreaks and compared this to the NNV for existing routine infant vaccination. We extended previous analyses of reactive vaccination by considering longer-term protection in vaccinees over five years, incorporating a proxy for indirect effects. We found that implementing reactive vaccination in previous pneumococcal meningitis outbreaks could have averted up to 10-20 % of outbreak cases, with the biggest potential impact in Brong Ahafo, Ghana (2015-2016) and Goundi, Chad (2009). The NNV, and hence the value of reactive vaccination, varied greatly. 'Large' (80 + cumulative modelled cases per 100,000 population) and/or 'prolonged' (exceeding a response threshold of 10 suspected cases per 100,000 per week for four weeks or more) outbreaks had NNV estimates under 10,000. For routine infant vaccination with PCV, the estimated NNV ranged from 3,100-5,600 in Burkina Faso and 1,500-2,600 in Ghana. IMPLICATIONS This analysis provides evidence to inform the design of pneumococcal meningitis outbreak response guidelines. Countries should consider reactive vaccination in each outbreak event, together with maintaining routine infant vaccination as the primary intervention to reduce pneumococcal disease burden and outbreak risk.
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Affiliation(s)
- Liza Hadley
- Disease Dynamics Unit, University of Cambridge, Cambridge, UK.
| | | | - Laura V Cooper
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | | | - Anderson Latt
- World Health Organization, Regional Office for Africa, Brazzaville, Congo
| | - Andre A Bita Fouda
- World Health Organization, Regional Office for Africa, Brazzaville, Congo
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Mahachi K, Kessels J, Boateng K, Jean Baptiste AE, Mitula P, Ekeman E, Nic Lochlainn L, Rosewell A, Sodha SV, Abela-Ridder B, Gabrielli AF. Zero- or missed-dose children in Nigeria: Contributing factors and interventions to overcome immunization service delivery challenges. Vaccine 2022; 40:5433-5444. [PMID: 35973864 PMCID: PMC9485449 DOI: 10.1016/j.vaccine.2022.07.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 06/11/2022] [Accepted: 07/24/2022] [Indexed: 11/28/2022]
Abstract
'Zero-dose' refers to a person who does not receive a single dose of any vaccine in the routine national immunization schedule, while 'missed dose' refers to a person who does not complete the schedule. These peopleremain vulnerable to vaccine-preventable diseases, and are often already disadvantaged due to poverty, conflict, and lack of access to basic health services. Globally, more 22.7 million children are estimated to be zero- or missed-dose, of which an estimated 3.1 million (∼14 %) reside in Nigeria.We conducted a scoping review tosynthesize recent literature on risk factors and interventions for zero- and missed-dosechildren in Nigeria. Our search identified 127 papers, including research into risk factors only (n = 66); interventions only (n = 34); both risk factors and interventions (n = 18); and publications that made recommendations only (n = 9). The most frequently reported factors influencing childhood vaccine uptake were maternal factors (n = 77), particularly maternal education (n = 22) and access to ante- and perinatal care (n = 19); heterogeneity between different types of communities - including location, region, wealth, religion, population composition, and other challenges (n = 50); access to vaccination, i.e., proximity of facilities with vaccines and vaccinators (n = 37); and awareness about immunization - including safety, efficacy, importance, and schedules (n = 18).Literature assessing implementation of interventions was more scattered, and heavily skewed towards vaccination campaigns and polio eradication efforts. Major evidence gaps exist in how to deliver effective and sustainable routine childhood immunization. Overall, further work is needed to operationalise the learnings from these studies, e.g. through applying findings to Nigeria's next review of vaccination plans, and using this summary as a basis for further investigation and specific recommendations on effective interventions.
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Affiliation(s)
- Kurayi Mahachi
- College of Public Health, University of Iowa, Iowa City, Iowa, United States
| | | | - Kofi Boateng
- Nigeria Country Office, World Health Organization, Abuja, Nigeria
| | | | - Pamela Mitula
- Inter-Country Support Team, Regional Office for Africa, World Health Organization, Ouagadougou, Burkina Faso
| | - Ebru Ekeman
- Department of Immunization, Vaccines and Biologicals (IVB), World Health Organization, Geneva, Switzerland
| | - Laura Nic Lochlainn
- Department of Immunization, Vaccines and Biologicals (IVB), World Health Organization, Geneva, Switzerland
| | - Alexander Rosewell
- Department of Immunization, Vaccines and Biologicals (IVB), World Health Organization, Geneva, Switzerland
| | - Samir V Sodha
- Department of Immunization, Vaccines and Biologicals (IVB), World Health Organization, Geneva, Switzerland
| | - Bernadette Abela-Ridder
- Department of Control of Neglected Tropical Diseases (NTD), World Health Organization, Geneva, Switzerland
| | - Albis Francesco Gabrielli
- Department of Control of Neglected Tropical Diseases (NTD), World Health Organization, Geneva, Switzerland.
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Soumahoro L, Abitbol V, Vicic N, Bekkat-Berkani R, Safadi MAP. Meningococcal Disease Outbreaks: A Moving Target and a Case for Routine Preventative Vaccination. Infect Dis Ther 2021; 10:1949-1988. [PMID: 34379309 PMCID: PMC8572905 DOI: 10.1007/s40121-021-00499-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/05/2021] [Indexed: 12/04/2022] Open
Abstract
Outbreaks of invasive meningococcal disease (IMD) are unpredictable, can be sudden and have devastating consequences. We conducted a non-systematic review of the literature in PubMed (1997-2020) to assess outbreak response strategies and the impact of vaccine interventions. Since 1997, IMD outbreaks due to serogroups A, B, C, W, Y and X have occurred globally. Reactive emergency mass vaccination campaigns have encompassed single institutions (schools, universities) through to whole sections of the population at regional/national levels (e.g. serogroup B outbreaks in Saguenay-Lac-Saint-Jean region, Canada and New Zealand). Emergency vaccination responses to IMD outbreaks consistently incurred substantial costs (expenditure on vaccine supplies, personnel costs and interruption of other programmes). Impediments included the limited pace of transmission of information to parents/communities/healthcare workers; issues around collection of informed consents; poor vaccine uptake by older adolescents/young adults, often a target age group; issues of reimbursement, particularly in the USA; and difficulties in swift supply of large quantities of vaccines. For serogroup B outbreaks, the need for two doses was a significant issue that contributed substantially to costs, delayed onset of protection and non-compliance with dose 2. Real-world descriptions of outbreak control strategies and the associated challenges systematically show that reactive outbreak management is administratively, logistically and financially costly, and that its impact can be difficult to measure. In view of the unpredictability, fast pace and potential lethality of outbreak-associated IMD, prevention through routine vaccination appears the most effective mitigation tool. Highly effective vaccines covering five of six disease-causing serogroups are available. Preparedness through routine vaccination programmes will enhance the speed and effectiveness of outbreak responses, should they be needed (ready access to vaccines and need for a single booster dose rather than a primary series).
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Affiliation(s)
| | | | | | | | - Marco A P Safadi
- Department of Pediatrics, Santa Casa de São Paulo School of Medical Sciences, São Paulo, Brazil
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Azam JM, Saitta B, Bonner K, Ferrari MJ, Pulliam JRC. Modelling the relative benefits of using the measles vaccine outside cold chain for outbreak response. Vaccine 2021; 39:5845-5853. [PMID: 34481696 DOI: 10.1016/j.vaccine.2021.08.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/30/2021] [Accepted: 08/13/2021] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Rapid outbreak response vaccination is a strategy for measles control and elimination. Measles vaccines must be stored and transported within a specified temperature range, but this can present significant challenges when targeting remote populations. Measles vaccine licensure for delivery outside cold chain (OCC) could provide more vaccine transport/storage space without ice packs, and a solution to shorten response times. However, due to vaccine safety and wastage considerations, the OCC strategy will require other operational changes, potentially including the use of 1-dose (monodose) instead of 10-dose vials, requiring larger transport/storage equipment currently achieved with 10-dose vials. These trade-offs require quantitative comparisons of vaccine delivery options to evaluate their relative benefits. METHODS We developed a modelling framework combining elements of the vaccine supply chain - cold chain, vial, team, and transport equipment types - with a measles transmission dynamics model to compare vaccine delivery options. We compared 10 strategies resulting from combinations of the vaccine supply elements and grouped into three main classes: OCC, partial cold chain (PCC), and full cold chain (FCC). For each strategy, we explored a campaign with 20 teams sequentially targeting 5 locations with 100,000 individuals each. We characterised the time needed to freeze ice packs and complete the campaign (campaign duration), vaccination coverage, and cases averted, assuming a fixed pre-deployment delay before campaign commencement. We performed sensitivity analyses of the pre-deployment delay, population sizes, and two team allocation schemes. RESULTS The OCC, PCC, and FCC strategies achieve campaign durations of 50, 51, and 52 days, respectively. Nine of the ten strategies can achieve a vaccination coverage of 80%, and OCC averts the most cases. DISCUSSION The OCC strategy, therefore, presents improved operational and epidemiological outcomes relative to current practice and the other options considered.
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Affiliation(s)
- James M Azam
- DSI-NRF Centre of Excellence in Epidemiological Modelling and Analysis, Stellenbosch University, Stellenbosch, South Africa.
| | - Barbara Saitta
- Access Campaign, Médecins Sans Frontières, New York, United States
| | - Kimberly Bonner
- University of Minnesota, Twin Cities, Minneapolis, United States
| | - Matthew J Ferrari
- The Center for Infectious Disease Dynamics, The Pennsylvania State University, PA, United States
| | - Juliet R C Pulliam
- DSI-NRF Centre of Excellence in Epidemiological Modelling and Analysis, Stellenbosch University, Stellenbosch, South Africa
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Hitchings MDT, Coldiron ME, Grais RF, Lipsitch M. Analysis of a meningococcal meningitis outbreak in Niger - potential effectiveness of reactive prophylaxis. PLoS Negl Trop Dis 2019; 13:e0007077. [PMID: 30856166 PMCID: PMC6428357 DOI: 10.1371/journal.pntd.0007077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/21/2019] [Accepted: 02/21/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Seasonal epidemics of bacterial meningitis in the African Meningitis Belt carry a high burden of disease and mortality. Reactive mass vaccination is used as a control measure during epidemics, but the time taken to gain immunity from the vaccine reduces the flexibility and effectiveness of these campaigns. Targeted reactive antibiotic prophylaxis could be used to supplement reactive mass vaccination and further reduce the incidence of meningitis, and the potential effectiveness and efficiency of these strategies should be explored. METHODS AND FINDINGS Data from an outbreak of meningococcal meningitis in Niger, caused primarily by Neisseria meningitidis serogroup C, is used to estimate clustering of meningitis cases at the household and village level. In addition, reactive antibiotic prophylaxis and reactive vaccination strategies are simulated to estimate their potential effectiveness and efficiency, with a focus on the threshold and spatial unit used to declare an epidemic and initiate the intervention. There is village-level clustering of suspected meningitis cases after an epidemic has been declared in a health area. Risk of suspected meningitis among household contacts of a suspected meningitis case is no higher than among members of the same village. Village-wide antibiotic prophylaxis can target subsequent cases in villages: across of range of parameters pertaining to how the intervention is performed, up to 220/672 suspected cases during the season are potentially preventable. On the other hand, household prophylaxis targets very few cases. In general, the village-wide strategy is not very sensitive to the method used to declare an epidemic. Finally, village-wide antibiotic prophylaxis is potentially more efficient than mass vaccination of all individuals at the beginning of the season, and than the equivalent reactive vaccination strategy. CONCLUSIONS Village-wide antibiotic prophylaxis should be considered and tested further as a response against outbreaks of meningococcal meningitis in the Meningitis Belt, as a supplement to reactive mass vaccination.
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Affiliation(s)
- Matt D. T. Hitchings
- Center for Communicable Disease Dynamics and Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA, United States of America
| | | | | | - Marc Lipsitch
- Center for Communicable Disease Dynamics and Departments of Epidemiology and Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, United States of America
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Campeau L, Degroote S, Ridde V, Carabali M, Zinszer K. Containment measures for emerging and re-emerging vector-borne and other infectious diseases of poverty in urban settings: a scoping review. Infect Dis Poverty 2018; 7:95. [PMID: 30173673 PMCID: PMC6120079 DOI: 10.1186/s40249-018-0478-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 08/06/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The emergence and re-emergence of vector-borne and other infectious diseases of poverty pose a threat to the health of populations living in urban and low-income settings. A detailed understanding of intervention strategies, including effectiveness of past outbreak containment, is necessary to improve future practices. The objective was to determine what is known about the effectiveness of containment measures for emerging and re-emerging vector-borne and other infectious diseases of poverty in urban settings and identify research gaps and implications for public health practice. MAIN BODY We conducted a scoping review and systematically searched peer-reviewed and grey literature published between 2000 and 2016. Different data extraction tools were used for data coding and extraction, and data on implementation process and transferability were extracted from all studies. A quality assessment was conducted for each included study. We screened 205 full-text articles and reports for a total of 31 articles included in the review. The quality of the studies was generally low to moderate. The largest body of evidence concerned control activities for Ebola virus and dengue fever. The majority of interventions (87%) relied on multiple types of measures, which were grouped into four categories: 1) healthcare provision; 2) epidemiological investigation and/or surveillance; 3) environmental or sanitary interventions; and 4) community-based interventions. The quality of the majority of studies (90%) was poor or moderate, and one-third of the studies did not provide a clear description of the outcomes and of the procedures and/or tools used for the intervention. CONCLUSIONS Our results highlight the difficulty of establishing causation when assessing the effect of containment measures. Studies that extend beyond solely reporting on effectiveness and take into account the complexity of real-world settings are urgently needed. We recommend the allocation of research efforts to the evaluation of the implementation processes of interventions as well as their comprehensive and systematic description using validated checklists.
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Affiliation(s)
- Laurence Campeau
- University of Montreal Public Health Research Institute (IRSPUM), Montreal, Quebec, Canada
| | - Stéphanie Degroote
- University of Montreal Public Health Research Institute (IRSPUM), Montreal, Quebec, Canada.
| | - Valery Ridde
- University of Montreal Public Health Research Institute (IRSPUM), Montreal, Quebec, Canada
- French Institute For Research on sustainable Development (IRD), IRD-Paris Descartes University (CEPED), Paris Sorbonne Cités University, Erl Inserm Sagesud, Paris, France
| | | | - Kate Zinszer
- University of Montreal Public Health Research Institute (IRSPUM), Montreal, Quebec, Canada
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Coldiron ME, Assao B, Page AL, Hitchings MDT, Alcoba G, Ciglenecki I, Langendorf C, Mambula C, Adehossi E, Sidikou F, Tassiou EI, De Lastours V, Grais RF. Single-dose oral ciprofloxacin prophylaxis as a response to a meningococcal meningitis epidemic in the African meningitis belt: A 3-arm, open-label, cluster-randomized trial. PLoS Med 2018; 15:e1002593. [PMID: 29944651 PMCID: PMC6019097 DOI: 10.1371/journal.pmed.1002593] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 05/21/2018] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Antibiotic prophylaxis for contacts of meningitis cases is not recommended during outbreaks in the African meningitis belt. We assessed the effectiveness of single-dose oral ciprofloxacin administered to household contacts and in village-wide distributions on the overall attack rate (AR) in an outbreak of meningococcal meningitis. METHODS AND FINDINGS In this 3-arm, open-label, cluster-randomized trial during a meningococcal meningitis outbreak in Madarounfa District, Niger, villages notifying a suspected case were randomly assigned (1:1:1) to standard care (the control arm), single-dose oral ciprofloxacin for household contacts within 24 hours of case notification, or village-wide distribution of ciprofloxacin within 72 hours of first case notification. The primary outcome was the overall AR of suspected meningitis after inclusion. A random sample of 20 participating villages was enrolled to document any changes in fecal carriage prevalence of ciprofloxacin-resistant and extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae before and after the intervention. Between April 22 and May 18, 2017, 49 villages were included: 17 to the control arm, 17 to household prophylaxis, and 15 to village-wide prophylaxis. A total of 248 cases were notified in the study after the index cases. The AR was 451 per 100,000 persons in the control arm, 386 per 100,000 persons in the household prophylaxis arm (t test versus control p = 0.68), and 190 per 100,000 persons in the village-wide prophylaxis arm (t test versus control p = 0.032). The adjusted AR ratio between the household prophylaxis arm and the control arm was 0.94 (95% CI 0.52-1.73, p = 0.85), and the adjusted AR ratio between the village-wide prophylaxis arm and the control arm was 0.40 (95% CI 0.19‒0.87, p = 0.022). No adverse events were notified. Baseline carriage prevalence of ciprofloxacin-resistant Enterobacteriaceae was 95% and of ESBL-producing Enterobacteriaceae was >90%, and did not change post-intervention. One limitation of the study was the small number of cerebrospinal fluid samples sent for confirmatory testing. CONCLUSIONS Village-wide distribution of single-dose oral ciprofloxacin within 72 hours of case notification reduced overall meningitis AR. Distributions of ciprofloxacin could be an effective tool in future meningitis outbreak responses, but further studies investigating length of protection, effectiveness in urban settings, and potential impact on antimicrobial resistance patterns should be carried out. TRIAL REGISTRATION ClinicalTrials.gov NCT02724046.
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Affiliation(s)
| | | | | | - Matt D. T. Hitchings
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | | | | | | | | | | | - Fati Sidikou
- Centre de Recherche Médicale et Sanitaire, Niamey, Niger
| | | | - Victoire De Lastours
- Department of Internal Medicine, Hôpital Beaujon, Assistance Publique–Hôpitaux de Paris, Paris, France
- IAME Research Group UMC1137, Université Paris Diderot, Paris, France
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Yaesoubi R, Trotter C, Colijn C, Yaesoubi M, Colombini A, Resch S, Kristiansen PA, LaForce FM, Cohen T. The cost-effectiveness of alternative vaccination strategies for polyvalent meningococcal vaccines in Burkina Faso: A transmission dynamic modeling study. PLoS Med 2018; 15:e1002495. [PMID: 29364884 PMCID: PMC5783340 DOI: 10.1371/journal.pmed.1002495] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 12/19/2017] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND The introduction of a conjugate vaccine for serogroup A Neisseria meningitidis has dramatically reduced disease in the African meningitis belt. In this context, important questions remain about the performance of different vaccine policies that target remaining serogroups. Here, we estimate the health impact and cost associated with several alternative vaccination policies in Burkina Faso. METHODS AND FINDINGS We developed and calibrated a mathematical model of meningococcal transmission to project the disability-adjusted life years (DALYs) averted and costs associated with the current Base policy (serogroup A conjugate vaccination at 9 months, as part of the Expanded Program on Immunization [EPI], plus district-specific reactive vaccination campaigns using polyvalent meningococcal polysaccharide [PMP] vaccine in response to outbreaks) and three alternative policies: (1) Base Prime: novel polyvalent meningococcal conjugate (PMC) vaccine replaces the serogroup A conjugate in EPI and is also used in reactive campaigns; (2) Prevention 1: PMC used in EPI and in a nationwide catch-up campaign for 1-18-year-olds; and (3) Prevention 2: Prevention 1, except the nationwide campaign includes individuals up to 29 years old. Over a 30-year simulation period, Prevention 2 would avert 78% of the meningococcal cases (95% prediction interval: 63%-90%) expected under the Base policy if serogroup A is not replaced by remaining serogroups after elimination, and would avert 87% (77%-93%) of meningococcal cases if complete strain replacement occurs. Compared to the Base policy and at the PMC vaccine price of US$4 per dose, strategies that use PMC vaccine (i.e., Base Prime and Preventions 1 and 2) are expected to be cost saving if strain replacement occurs, and would cost US$51 (-US$236, US$490), US$188 (-US$97, US$626), and US$246 (-US$53, US$703) per DALY averted, respectively, if strain replacement does not occur. An important potential limitation of our study is the simplifying assumption that all circulating meningococcal serogroups can be aggregated into a single group; while this assumption is critical for model tractability, it would compromise the insights derived from our model if the effectiveness of the vaccine differs markedly between serogroups or if there are complex between-serogroup interactions that influence the frequency and magnitude of future meningitis epidemics. CONCLUSIONS Our results suggest that a vaccination strategy that includes a catch-up nationwide immunization campaign in young adults with a PMC vaccine and the addition of this new vaccine into EPI is cost-effective and would avert a substantial portion of meningococcal cases expected under the current World Health Organization-recommended strategy of reactive vaccination. This analysis is limited to Burkina Faso and assumes that polyvalent vaccines offer equal protection against all meningococcal serogroups; further studies are needed to evaluate the robustness of this assumption and applicability for other countries in the meningitis belt.
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Affiliation(s)
- Reza Yaesoubi
- Department of Health Policy and Management, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - Caroline Trotter
- Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Caroline Colijn
- Department of Mathematics, Imperial College London, London, United Kingdom
- Centre for Mathematics of Precision Healthcare, Imperial College London, London, United Kingdom
| | - Maziar Yaesoubi
- Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, New Mexico, United States of America
| | | | - Stephen Resch
- Department of Health Policy and Management, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Paul A. Kristiansen
- Department of Bacteriology, Norwegian Institute of Public Health, Oslo, Norway
| | | | - Ted Cohen
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, United States of America
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LaForce FM, Djingarey M, Viviani S, Preziosi MP. Lessons from the Meningitis Vaccine Project. Viral Immunol 2017; 31:109-113. [PMID: 29116892 DOI: 10.1089/vim.2017.0120] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
From 2001 to 2017 the Meningitis Vaccine Project (MVP), a Gates Foundation funded partnership between PATH and the World Health Organization (WHO), successfully developed, tested, licensed, and introduced an affordable new Group A meningococcal conjugate vaccine, MenAfriVac, in sub-Saharan Africa. The vaccine was well received, and from 2010 to 2016, over 260 million Africans have received a dose of the vaccine in campaigns largely directed at 1–29-year olds. The public health impact has been dramatic with the elimination of Group A meningococcal infections wherever the vaccine has been used at public health scale. Over its 16-year life span, MVP faced many challenges, and lessons were learned that may be of interest to other groups seeking to develop vaccine products for resource-poor countries. We have chosen to highlight six elements that were keys to the success of the project: (a) country and African regional engagement during all phases of the project; (b) the evolution of the WHO/PATH partnership; (c) funding the introduction of MenAfriVac in meningitis belt countries; (d) regulatory challenges; (e) clinical trials in Africa and India; and (f ) the realities of vaccine development partnerships.
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Coldiron ME, Alcoba G, Ciglenecki I, Hitchings M, Djibo A, Page AL, Langendorf C, Grais RF. Ciprofloxacin for contacts of cases of meningococcal meningitis as an epidemic response: study protocol for a cluster-randomized trial. Trials 2017; 18:294. [PMID: 28646924 PMCID: PMC5482956 DOI: 10.1186/s13063-017-2028-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 05/31/2017] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Epidemics of meningococcal meningitis are common in the "African meningitis belt." Current response strategies include reactive vaccination campaigns, which are often organized too late to have maximal impact. A novel strain of Neisseria meningitidis serogroup C has been circulating in recent years, and vaccine supplies are limited. An evaluation of chemoprophylaxis with single-dose ciprofloxacin for household contacts of meningitis cases has therefore been recommended. METHODS/DESIGN A three-arm cluster-randomized trial has been designed for implementation during a meningococcal meningitis epidemic in a health district in Niger in which at least two Health Zones (HZs) have met the weekly epidemic threshold. The primary outcome is the incidence (attack rate) of meningitis during the epidemic. Villages will be randomized in a 1:1:1 ratio to one of three different arms: standard care, household-level prophylaxis, or village-wide prophylaxis. After study launch, when a case of meningococcal meningitis is identified in an HZ, the first reported case from a village will trigger the inclusion and randomization of the village. Household-level prophylaxis with single-dose ciprofloxacin will be offered in the home to all household members within 24 hours of the notification of the case, and village-wide distributions will occur within 72 hours of the notification of the case. The sample size necessary to detect differences between each of the two intervention arms and the standard care arm will be set after 4 weeks of data collection, in order to quantify multiple variables that could be particular to a given area. The primary analysis will compare attack rates at the end of the epidemic in each of the three arms. A nested sub-study will assess the effects of ciprofloxacin prophylaxis on the prevalence of ciprofloxacin-resistant enterobacteriaceae. A total of 200 participants in the standard care arm and 200 in the village-wide prophylaxis arm will provide stool samples at days 0, 7, and 28 following their village's inclusion in the study. DISCUSSION An innovative trial is proposed for implementation during an epidemic that will assess the impact of a novel strategy for meningitis outbreak response. In parallel, we will describe potential negative effects of the intervention. TRIAL REGISTRATION ClinicalTrials.gov, NCT02724046 . Registered on 15 March 2016. Last updated on 13 June 2017.
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Affiliation(s)
| | - Gabriel Alcoba
- Médecins Sans Frontières, 78 rue de Lausanne, Geneva, Switzerland
| | - Iza Ciglenecki
- Médecins Sans Frontières, 78 rue de Lausanne, Geneva, Switzerland
| | - Matt Hitchings
- Harvard T.H. Chan School of Public Health, Boston, MA USA
| | - Ali Djibo
- Niamey National Hospital, Niamey, Niger
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Buckee CO, Tatem AJ, Metcalf CJE. Seasonal Population Movements and the Surveillance and Control of Infectious Diseases. Trends Parasitol 2016; 33:10-20. [PMID: 27865741 DOI: 10.1016/j.pt.2016.10.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 10/08/2016] [Accepted: 10/19/2016] [Indexed: 10/20/2022]
Abstract
National policies designed to control infectious diseases should allocate resources for interventions based on regional estimates of disease burden from surveillance systems. For many infectious diseases, however, there is pronounced seasonal variation in incidence. Policy-makers must routinely manage a public health response to these seasonal fluctuations with limited understanding of their underlying causes. Two complementary and poorly described drivers of seasonal disease incidence are the mobility and aggregation of human populations, which spark outbreaks and sustain transmission, respectively, and may both exhibit distinct seasonal variations. Here we highlight the key challenges that seasonal migration creates when monitoring and controlling infectious diseases. We discuss the potential of new data sources in accounting for seasonal population movements in dynamic risk mapping strategies.
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Affiliation(s)
- Caroline O Buckee
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, USA; Center for Communicable Disease Dynamics, Harvard T.H. Chan School of Public Health, Boston, USA.
| | - Andrew J Tatem
- Flowminder Foundation, Stockholm, Sweden; WorldPop, Department of Geography and Environment, University of Southampton, Southampton, UK
| | - C Jessica E Metcalf
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, USA; Office of Population Research, Woodrow Wilson School, Princeton University, Princeton, USA
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Colombini A, Trotter C, Madrid Y, Karachaliou A, Preziosi MP. Costs of Neisseria meningitidis Group A Disease and Economic Impact of Vaccination in Burkina Faso. Clin Infect Dis 2016; 61 Suppl 5:S473-82. [PMID: 26553677 PMCID: PMC4639502 DOI: 10.1093/cid/civ600] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Background. Five years since the successful introduction of MenAfriVac in a mass vaccination campaign targeting 1- to 29-year-olds in Burkina Faso, consideration must be given to the optimal strategies for sustaining population protection. This study aims to estimate the economic impact of a range of vaccination strategies in Burkina Faso. Methods. We performed a cost-of-illness study, comparing different vaccination scenarios in terms of costs to both households and health systems over a 26-year time horizon. These scenarios are (1) reactive vaccination campaign (baseline comparator); (2) preventive vaccination campaign; (3) routine immunization at 9 months; and (4) a combination of routine and an initial catchup campaign of children under 5. Costs were estimated from a literature review, which included unpublished programmatic documents and peer-reviewed publications. The future disease burden for each vaccination strategy was predicted using a dynamic transmission model of group A Neisseria meningitidis. Results. From 2010 to 2014, the total costs associated with the preventive campaign targeting 1- to 29-year-olds with MenAfriVac were similar to the estimated costs of the reactive vaccination strategy (approximately 10 million US dollars [USD]). Between 2015 and 2035, routine immunization with or without a catch-up campaign of 1- to 4-year-olds is cost saving compared with the reactive strategy, both with and without discounting costs and cases. Most of the savings are accrued from lower costs of case management and household costs resulting from a lower burden of disease. After the initial investment in the preventive strategy, 1 USD invested in the routine strategy saves an additional 1.3 USD compared to the reactive strategy. Conclusions. Prevention strategies using MenAfriVac will be significantly cost saving in Burkina Faso, both for the health system and for households, compared with the reactive strategy. This will protect households from catastrophic expenditures and increase the development capacity of the population.
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Affiliation(s)
- Anaïs Colombini
- Independent Consultant, World Health Organization Initiative for Vaccine Research, Geneva, Switzerland
| | - Caroline Trotter
- Disease Dynamics Unit, Department of Veterinary Medicine, University of Cambridge, United Kingdom
| | | | - Andromachi Karachaliou
- Disease Dynamics Unit, Department of Veterinary Medicine, University of Cambridge, United Kingdom
| | - Marie-Pierre Preziosi
- Meningitis Vaccine Project, Department of Immunization, Vaccines and Biologicals, World Health Organization, Geneva, Switzerland Meningitis Vaccine Project, PATH, Ferney-Voltaire, France
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Control of meningitis outbreaks in the African meningitis belt. THE LANCET. INFECTIOUS DISEASES 2016; 16:400-2. [PMID: 27036337 DOI: 10.1016/s1473-3099(16)00121-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 02/18/2016] [Indexed: 11/20/2022]
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Trotter CL, Cibrelus L, Fernandez K, Lingani C, Ronveaux O, Stuart JM. Response thresholds for epidemic meningitis in sub-Saharan Africa following the introduction of MenAfriVac®. Vaccine 2015; 33:6212-7. [PMID: 26463444 DOI: 10.1016/j.vaccine.2015.09.107] [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: 07/28/2015] [Revised: 09/28/2015] [Accepted: 09/29/2015] [Indexed: 10/22/2022]
Abstract
BACKGROUND Since 2010, countries in the African meningitis belt have been introducing a new serogroup A meningococcal conjugate vaccine (MenAfriVac(®)) through mass campaigns. With the subsequent decline in meningitis due to Neisseria meningitidis serogroup A (NmA) and relative increase in meningitis due to other serogroups, mainly N. meningitidis serogroup W (NmW), the World Health Organisation (WHO) initiated a review of the incidence thresholds that guide response to meningitis epidemics in the African meningitis belt. METHODS Meningitis surveillance data from African meningitis belt countries from 2002 to 2013 were used to construct a single NmW dataset. The performance of different weekly attack rates, used as thresholds to initiate vaccination response, on preventing further cases was estimated. The cumulative seasonal attack rate used to define an epidemic was also varied. RESULTS Considerable variation in effect at different thresholds was observed. In predicting epidemics defined as a seasonal cumulative incidence of 100/10(5) population, an epidemic threshold of 10 cases/10(5) population/week performed well. Based on this same epidemic threshold, with a 6 week interval between crossing the epidemic threshold and population protection from a meningococcal vaccination campaign, an estimated 17 cases per event would be prevented by vaccination. Lowering the threshold increased the number of cases per event potentially prevented, as did shortening the response interval. If the interval was shortened to 4 weeks at the threshold of 10/10(5), the number of cases prevented would increase to 54 per event. CONCLUSIONS Accelerating time to vaccination could prevent more cases per event than lowering the threshold. Once the meningitis epidemic threshold is crossed, it is of critical importance that vaccination campaigns, where appropriate, are initiated rapidly.
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Affiliation(s)
| | - Laurence Cibrelus
- Department of Pandemic and Epidemic Diseases, World Health Organization, Geneva, Switzerland
| | - Katya Fernandez
- Department of Pandemic and Epidemic Diseases, World Health Organization, Geneva, Switzerland
| | - Clément Lingani
- World Health Organization, AFRO Inter-Country Support Team for West Africa, Ouagadougou, Burkina Faso
| | - Olivier Ronveaux
- Department of Pandemic and Epidemic Diseases, World Health Organization, Geneva, Switzerland
| | - James M Stuart
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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Carod Artal FJ. Meningococcal meningitis: vaccination outbreak response and epidemiological changes in the African meningitis belt. Int Health 2015; 7:226-7. [DOI: 10.1093/inthealth/ihv025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 03/25/2015] [Indexed: 11/12/2022] Open
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