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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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Brotes de Enfermedades , Meningitis Neumocócica , Vacunas Neumococicas , Humanos , Brotes de Enfermedades/prevención & control , Meningitis Neumocócica/prevención & control , Meningitis Neumocócica/epidemiología , Ghana/epidemiología , Burkina Faso/epidemiología , Lactante , Vacunas Neumococicas/administración & dosificación , Modelos Teóricos , Vacunación , Chad/epidemiología , Vacunas Conjugadas/administración & dosificación , Preescolar , Niño , FemeninoRESUMEN
BACKGROUND: The Banalia health zone in the Democratic Republic of Congo reported a meningitis epidemic in 2021 that evolved outside the epidemic season. We assessed the effects of the meningitis epidemic response. METHODS: The standard case definition was used to identify cases. Care was provided to 2651 in-patients, with 8% of them laboratory tested, and reactive vaccination was conducted. To assess the effects of reactive vaccination and treatment with ceftriaxone, a statistical analysis was performed. RESULTS: Overall, 2662 suspected cases of meningitis with 205 deaths were reported. The highest number of cases occurred in the 30-39 years age group (927; 38.5%). Ceftriaxone contributed to preventing deaths with a case fatality rate that decreased from 70.4% before to 7.7% after ceftriaxone was introduced (p = 0.001). Neisseria meningitidis W was isolated, accounting for 47/57 (82%), of which 92% of the strains belonged to the clonal complex 11. Reactive vaccination of individuals in Banalia aged 1-19 years with a meningococcal multivalent conjugate (ACWY) vaccine (Menactra®) coverage of 104.6% resulted in an 82% decline in suspected meningitis cases (incidence rate ratio, 0.18; 95% confidence interval, 0.02-0.80; p = 0.041). CONCLUSION: Despite late detection (two months) and reactive vaccination four months after crossing the epidemic threshold, interventions implemented in Banalia contributed to the control of the epidemic.
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Following the West Africa Ebola virus disease outbreak (2013-2016), the Joint External Evaluation (JEE) is one of the three voluntary components recommended by the WHO for evaluating the International Health Regulations (2005) capacities in countries. Here, we share experience implementing JEEs in all 47 countries in the WHO African region. In February 2016, the United Republic of Tanzania (Mainland) was the first country globally to conduct a JEE. By April 2022, JEEs had been conducted in all 47 countries plus in the island of Zanzibar. A total of 360 subject matter experts (SMEs) from 88 organisations were deployed 607 times. Despite availability of guidelines, the process had to be contextualised while avoiding jeopardising the quality and integrity of the findings. Key challenges were: inadequate understanding of the process by in-country counterparts; competing country priorities; limited time for validating subnational capacities; insufficient availability of SMEs for biosafety and biosecurity, antimicrobial resistance, points of entry, chemical events and radio-nuclear emergencies; and inadequate financing to fill gaps identified. Key points learnt were: importance of country leadership and ownership; conducting orientation workshops before the self-assessment; availability of an external JEE expert to support the self-assessment; the skills, attitudes and leadership competencies of the team lead; identifying national experts as SMEs for future JEEs to promote capacity building and experience sharing; the centrality of involving One Health stakeholders from the beginning to the end of the process; and the need for dedicated staff for planning, coordination, implementation and timely report writing. Moving forward, it is essential to draw from this learning to plan future JEEs. Finally, predictable financing is needed immediately to fill gaps identified.
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Salud Global , Salud Pública , Humanos , Organización Mundial de la Salud , Cooperación Internacional , Reglamento Sanitario InternacionalRESUMEN
Background: As of the end of 2021, twenty-four countries in the African meningitis belt have rolled out mass campaigns of MenAfriVac®, a meningococcal A conjugate vaccine (MACV) first introduced in 2010. Twelve have completed introduction of MACV into routine immunisation (RI) schedules. Although select post-campaign coverage data are published, no study currently comprehensively estimates MACV coverage from both routine and campaign sources in the meningitis belt across age, country, and time. Methods: In this modelling study, we assembled campaign data from the twenty-four countries that had introduced any immunisation activity during or before the year 2021 (Benin, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Côte d'Ivoire, Democratic Republic of the Congo, Ethiopia, Eritrea, the Gambia, Ghana, Guinea, Guinea Bissau, Kenya, Mali, Mauritania, Niger, Nigeria, Senegal, South Sudan, Sudan, Togo and Uganda) via WHO reports and RI data via systematic review. Next, we modelled RI coverage using Spatiotemporal Gaussian Process Regression. Then, we synthesized these estimates with campaign data into a cohort model, tracking coverage for each age cohort from age 1 to 29 years over time for each country. Findings: Coverage in high-risk locations amongst children aged 1-4 in 2021 was estimated to be highest in Togo with 96.0% (95% uncertainty interval [UI] 92.0-99.0), followed by Niger with 87.2% (95% UI 85.3-89.0) and Burkina Faso, with 86.4% (95% UI 85.1-87.6). These countries had high coverage values driven by an initial successful mass immunisation campaign, followed by a catch-up campaign, followed by introduction of RI. Due to the influence of older mass vaccination campaigns, coverage proportions skewed higher in the 1-29 age group than the 1-4 group, with a median coverage of 82.9% in 2021 in the broader age group compared to 45.6% in the narrower age group. Interpretation: These estimates highlight where gaps in immunisation remain and emphasise the need for broader efforts to strengthen RI systems. This methodological framework can be applied to estimate coverage for any vaccine that has been delivered in both routine and supplemental immunisation activities. Funding: Bill and Melinda Gates Foundation.
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West African countries are hit annually by meningitis outbreaks which occur during the dry season and are linked to atmospheric variability. This paper describes an innovative co-production process between the African Centre of Meteorological Applications for Development (ACMAD; forecast producer) and the World Health Organisation Regional Office for Africa (WHO AFRO; forecast user) to support awareness, preparedness and response actions for meningitis outbreaks. Using sub-seasonal to seasonal (S2S) forecasts, this co-production enables ACMAD and WHO AFRO to build initiative that increases the production of useful climate services in the health sector. Temperature and relative humidity forecasts are combined with dust forecasts to operationalize a meningitis early warning system (MEWS) across the African meningitis belt with a two-week lead time. To prevent and control meningitis, the MEWS is produced from week 1 to 26 of the year. This study demonstrates that S2S forecasts have good skill at predicting dry and warm atmospheric conditions precede meningitis outbreaks. Vigilance levels objectively defined within the MEWS are consistent with reported cases of meningitis. Alongside developing a MEWS, the co-production process provided a framework for analysis of climate and environmental risks based on reanalysis data, meningitis burden, and health service assessment, to support the development of a qualitative roadmap of country prioritization for defeating meningitis by 2030 across the WHO African region. The roadmap has enabled the identification of countries most vulnerable to meningitis epidemics, and in the context of climate change, supports plans for preventing, preparing, and responding to meningitis outbreaks.
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BACKGROUND: From May 2018 to September 2022, the Democratic Republic of Congo (DRC) experienced seven Ebola virus disease (EVD) outbreaks within its borders. During the 10th EVD outbreak (2018-2020), the largest experienced in the DRC and the second largest and most prolonged EVD outbreak recorded globally, a WHO risk assessment identified nine countries bordering the DRC as moderate to high risk from cross border importation. These countries implemented varying levels of Ebola virus disease preparedness interventions. This case study highlights the gains and shortfalls with the Ebola virus disease preparedness interventions within the various contexts of these countries against the background of a renewed and growing commitment for global epidemic preparedness highlighted during recent World Health Assembly events. MAIN TEXT: Several positive impacts from preparedness support to countries bordering the affected provinces in the DRC were identified, including development of sustained capacities which were leveraged upon to respond to the subsequent coronavirus disease 2019 (COVID-19) pandemic. Shortfalls such as lost opportunities for operationalizing cross-border regional preparedness collaboration and better integration of multidisciplinary perspectives, vertical approaches to response pillars such as surveillance, over dependence on external support and duplication of efforts especially in areas of capacity building were also identified. A recurrent theme that emerged from this case study is the propensity towards implementing short-term interventions during active Ebola virus disease outbreaks for preparedness rather than sustainable investment into strengthening systems for improved health security in alignment with IHR obligations, the Sustainable Development Goals and advocating global policy for addressing the larger structural determinants underscoring these outbreaks. CONCLUSIONS: Despite several international frameworks established at the global level for emergency preparedness, a shortfall exists between global policy and practice in countries at high risk of cross border transmission from persistent Ebola virus disease outbreaks in the Democratic Republic of Congo. With renewed global health commitment for country emergency preparedness resulting from the COVID-19 pandemic and cumulating in a resolution for a pandemic preparedness treaty, the time to review and address these gaps and provide recommendations for more sustainable and integrative approaches to emergency preparedness towards achieving global health security is now.
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COVID-19 , Fiebre Hemorrágica Ebola , Humanos , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , República Democrática del Congo/epidemiología , Pandemias/prevención & control , COVID-19/epidemiología , COVID-19/prevención & control , Brotes de Enfermedades/prevención & controlRESUMEN
On August 14, 2017, a 6-kilometer mudslide occurred in Regent Area, Western Area District of Sierra Leone following a torrential downpour that lasted 3 days. More than 300 houses along River Juba were submerged; 1141 people were reported dead or missing and 5905 displaced. In response to the mudslide, the World Health Organization (WHO) Country Office in Sierra Leone moved swiftly to verify the emergency and constitute an incident management team to coordinate the response. Early contact was made with the Ministry of Health and Sanitation and health sector partners. A Public Health Emergency Operations Center was set up to coordinate the response. Joint assessments, planning, and response among health sector partners ensured effectiveness and efficiency. Oral cholera vaccination was administered to high-risk populations to prevent a cholera outbreak. Surveillance for 4 waterborne diseases was enhanced through daily reporting from 9 health facilities serving the affected population. Performance standards from the WHO Emergency Response Framework were used to monitor the emergency response. An assessment of the country's performance showed that the country's response was well executed. To improve future response, we recommend enhanced district level preparedness, update of disaster response protocols, and pre-disaster mapping of health sector partners.
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Deslizamientos de Tierra/estadística & datos numéricos , Salud Pública/métodos , Defensa Civil/instrumentación , Defensa Civil/tendencias , Humanos , Salud Pública/estadística & datos numéricos , Sierra LeonaRESUMEN
BACKGROUND: The Ministry of Health and Sanitation (MOHS) in Sierra Leone partially rolled out the implementation of Integrated Disease Surveillance and Response (IDSR) in 2003. After the Ebola virus disease outbreak in 2014-2015, there was need to strengthen IDSR to ensure prompt detection and response to epidemic-prone diseases. We describe the processes, successes and challenges of revitalizing public health surveillance in a country recovering from a protracted Ebola virus disease outbreak. METHODS: The revitalization process began with adaptation of the revised IDSR guidelines and development of customized guidelines to suit the health care systems in Sierra Leone. Public health experts defined data flow, system operations, case definitions, frequency and channels of reporting and dissemination. Next, phased training of IDSR focal persons in each health facility and the distribution of data collection and reporting tools was done. Monitoring activities included periodic supportive supervision and data quality assessments. Rapid response teams were formed to investigate and respond to disease outbreak alerts in all districts. RESULTS: Submission of reports through the IDSR system began in mid-2015 and by the 35th epidemiologic week, all district health teams were submitting reports. The key performance indicators measuring the functionality of the IDSR system in 2016 and 2017 were achieved (WHO Africa Region target ≥80%); the annual average proportion of timely weekly health facility reports submitted to the next level was 93% in 2016 and 97% in 2017; the proportion of suspected outbreaks and public health events detected through the IDSR system was 96% (n = 87) in 2016 and 100% (n = 85) in 2017. CONCLUSION: With proper planning, phased implementation and adequate investment of resources, it is possible to establish a functional IDSR system in a country recovering from a public health crisis. A functional IDSR system requires well trained workforce, provision of the necessary tools and guidelines, information, communication and technology infrastructure to support data transmission, provision of timely feedback as well as logistical support.