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1.
Am J Trop Med Hyg ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39378872

RESUMO

During the COVID-19 pandemic, the need for making testing readily available was recognized as an important factor for individuals to help make informed decisions, including to isolate or seek care, and for policymakers to control transmission. Toward this end, FIND and the Access to COVID-19 Tools Accelerator funded 16 rapid operational research studies and one implementation project in Africa, the Caribbean, and Asia evaluating the utility, acceptability, and feasibility of different community-based SARS-CoV-2 testing approaches. Here, we discuss common factors and challenges encountered during study implementation. We note six key factors essential for success: 1) collaboration and partnerships; 2) buy-in of local stakeholders, including communities; 3) access to affordable supplies; 4) flexible financing; 5) effective approval systems; and 6) a skilled and motivated workforce. We also note various challenges that must be addressed to fully capitalize on these success factors. In particular, ethics committees are often not well equipped to assess operational research during outbreaks. Outbreaks, especially of novel pathogens, are unpredictable, and transmission dynamics are even more likely to change if the pathogen is prone to frequent mutations, such as SARS-CoV-2. Research that aims to evaluate strategies for curbing transmission must hence be easily and swiftly adaptable. This requires flexibility from researchers, funders, staff conducting the studies, and ethics and other approval committees. International guidelines for evaluating operational research protocols in outbreaks are needed to provide timely evidence to enable informed decisions by individuals, communities, and policymakers, thereby reducing both the human and the economic impact of outbreaks.

2.
Vaccines (Basel) ; 12(8)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39203955

RESUMO

During the 2018-2020 Ebola virus disease outbreak in Democratic Republic of the Congo, a phase 3 trial of the Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine (DRC-EB-001) commenced in Goma, with participants being offered the two-dose regimen given 56 days apart. Suspension of trial activities in 2020 due to the COVID-19 pandemic led to some participants receiving a late dose 2 outside the planned interval. Blood samples were collected from adults, adolescents, and children prior to their delayed dose 2 vaccination and 21 days after, and tested for IgG binding antibodies against Ebola virus glycoprotein using the Filovirus Animal Nonclinical Group (FANG) ELISA. Results from 133 participants showed a median two-dose interval of 9.3 months. The pre-dose 2 antibody geometric mean concentration (GMC) was 217 ELISA Units (EU)/mL (95% CI 157; 301) in adults, 378 EU/mL (281; 510) in adolescents, and 558 EU/mL (471; 661) in children. At 21 days post-dose 2, the GMC increased to 22,194 EU/mL (16,726; 29,449) in adults, 37,896 EU/mL (29,985; 47,893) in adolescents, and 34,652 EU/mL (27,906; 43,028) in children. Participants receiving a delayed dose 2 had a higher GMC at 21 days post-dose 2 than those who received a standard 56-day regimen in other African trials, but similar to those who received the regimen with an extended interval.

3.
Vaccines (Basel) ; 12(8)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39203952

RESUMO

During the 2018-2020 Ebola virus disease (EVD) outbreak, residents in Goma, Democratic Republic of the Congo, were offered a two-dose prophylactic EVD vaccine. This was the first study to evaluate the safety of this vaccine in pregnant women. Adults, including pregnant women, and children aged ≥1 year old were offered the Ad26.ZEBOV (day 0; dose 1), MVA-BN-Filo (day 56; dose 2) EVD vaccine through an open-label clinical trial. In total, 20,408 participants, including 6635 (32.5%) children, received dose 1. Fewer than 1% of non-pregnant participants experienced a serious adverse event (SAE) following dose 1; one SAE was possibly related to the Ad26.ZEBOV vaccine. Of the 1221 pregnant women, 371 (30.4%) experienced an SAE, with caesarean section being the most common event. No SAEs in pregnant women were considered related to vaccination. Of 1169 pregnancies with a known outcome, 55 (4.7%) ended in a miscarriage, and 30 (2.6%) in a stillbirth. Eleven (1.0%) live births ended in early neonatal death, and five (0.4%) had a congenital abnormality. Overall, 188/891 (21.1%) were preterm births and 79/1032 (7.6%) had low birth weight. The uptake of the two-dose regimen was high: 15,328/20,408 (75.1%). The vaccine regimen was well-tolerated among the study participants, including pregnant women, although further data, ideally from controlled trials, are needed in this crucial group.

4.
Lancet Infect Dis ; 24(11): e696-e706, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38964363

RESUMO

In 2016, WHO designated Lassa fever a priority disease for epidemic preparedness as part of the WHO Blueprint for Action to Prevent Epidemics. One aspect of preparedness is to promote development of effective medical countermeasures (ie, diagnostics, therapeutics, and vaccines) against Lassa fever. Diagnostic testing for Lassa fever has important limitations and key advancements are needed to ensure rapid and accurate diagnosis. Additionally, the only treatment available for Lassa fever is ribavirin, but controversy exists regarding its effectiveness. Finally, no licensed vaccines are available for the prevention and control of Lassa fever. Ongoing epidemiological and behavioural studies are also crucial in providing actionable information for medical countermeasure development, use, and effectiveness in preventing and treating Lassa fever. This Personal View provides current research priorities for development of Lassa fever medical countermeasures based on literature published primarily in the last 5 years and consensus opinion of 20 subject matter experts with broad experience in public health or the development of diagnostics, therapeutics, and vaccines for Lassa fever. These priorities provide an important framework to ensure that Lassa fever medical countermeasures are developed and readily available for use in endemic and at-risk areas by the end of the decade.


Assuntos
Febre Lassa , Febre Lassa/prevenção & controle , Febre Lassa/diagnóstico , Febre Lassa/epidemiologia , Humanos , Vírus Lassa , Contramedidas Médicas , Pesquisa , Antivirais/uso terapêutico , Pesquisa Biomédica/tendências , Organização Mundial da Saúde
7.
BMC Med ; 21(1): 439, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964296

RESUMO

BACKGROUND: Marburg virus disease is an acute haemorrhagic fever caused by Marburg virus. Marburg virus is zoonotic, maintained in nature in Egyptian fruit bats, with occasional spillover infections into humans and nonhuman primates. Although rare, sporadic cases and outbreaks occur in Africa, usually associated with exposure to bats in mines or caves, and sometimes with secondary human-to-human transmission. Outbreaks outside of Africa have also occurred due to importation of infected monkeys. Although all previous Marburg virus disease outbreaks have been brought under control without vaccination, there is nevertheless the potential for large outbreaks when implementation of public health measures is not possible or breaks down. Vaccines could thus be an important additional tool, and development of several candidate vaccines is under way. METHODS: We developed a branching process model of Marburg virus transmission and investigated the potential effects of several prophylactic and reactive vaccination strategies in settings driven primarily by multiple spillover events as well as human-to-human transmission. Linelist data from the 15 outbreaks up until 2022, as well as an Approximate Bayesian Computational framework, were used to inform the model parameters. RESULTS: Our results show a low basic reproduction number which varied across outbreaks, from 0.5 [95% CI 0.05-1.8] to 1.2 [95% CI 1.0-1.9] but a high case fatality ratio. Of six vaccination strategies explored, the two prophylactic strategies (mass and targeted vaccination of high-risk groups), as well as a combination of ring and targeted vaccination, were generally most effective, with a probability of potential outbreaks being terminated within 1 year of 0.90 (95% CI 0.90-0.91), 0.89 (95% CI 0.88-0.90), and 0.88 (95% CI 0.87-0.89) compared with 0.68 (0.67-0.69) for no vaccination, especially if the outbreak is driven by zoonotic spillovers and the vaccination campaign initiated as soon as possible after onset of the first case. CONCLUSIONS: Our study shows that various vaccination strategies can be effective in helping to control outbreaks of MVD, with the best approach varying with the particular epidemiologic circumstances of each outbreak.


Assuntos
Quirópteros , Doença do Vírus de Marburg , Marburgvirus , Vacinas , Animais , Humanos , Doença do Vírus de Marburg/epidemiologia , Doença do Vírus de Marburg/prevenção & controle , Teorema de Bayes , Surtos de Doenças/prevenção & controle , Vacinação , Modelos Teóricos
10.
Lancet ; 401(10390): 1822-1824, 2023 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-37146622

RESUMO

Mpox (formerly known as monkeypox) is a zoonotic viral disease endemic in parts of Africa. In May, 2022, the world was alerted to circulation of monkeypox virus in many high-income countries outside of Africa. Continued spread resulted in a WHO declaration of a Public Health Emergency of International Concern. Although there has been much attention on the global outbreak, most of the focus has been on high-income countries outside of Africa, despite the fact that monkeypox virus has been causing disease in parts of Africa for at least 50 years. Furthermore, the long-term consequences of this event, especially the risk that mpox fills the niche vacated through smallpox eradication, have not been sufficiently considered. The heart of the problem is the historical neglect of mpox in Africa where the disease is endemic, and the actual and potential consequences if this neglect is left uncorrected.


Assuntos
Mpox , Varíola , Humanos , Animais , Varíola/epidemiologia , Mpox/epidemiologia , Zoonoses , África/epidemiologia , Surtos de Doenças , Monkeypox virus
12.
Soc Sci Med ; 323: 115833, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36934528

RESUMO

During the 10th Ebola virus disease (EVD) epidemic in the eastern Democratic Republic of the Congo (DRC) (2018-2020), two experimental EVD vaccines were deployed in North Kivu. This province has been at the centre of conflict in the region for the last 25 years. Amidst ambivalence towards protracted foreign intervention and controversy about introducing two experimental vaccines, the existing literature has focused on mistrust and 'resistance' towards the Ebola response and vaccines. In this article, we examine why people in the eastern DRC did decide to volunteer for a trial of a second EVD vaccine in North Kivu, despite the controversy. Drawing on ethnographic observation, interviews, and focus groups with trial participants conducted between September 2020 and April 2021, we analyse three motivations for participating: protection, health seeking, and expectations surrounding travel requirements. We make three points. First, participation in vaccine trials may be understood locally to have advantages which have not been considered by the trial, because they go beyond medical considerations and are specific to a particular social setting. Second, despite much of the literature focusing on a causal relationship between rumours and 'vaccine hesitancy', some rumours may in fact encourage participation. Third, material objects associated with trial participation - such as participant vaccine cards - can hold social and political meaning beyond the confines of the vaccine clinic, and influence decisions surrounding participation. Empirical investigation of how medical interventions become entangled in political economies is essential to understanding the perceived functions of participation, and thus the reasons why people volunteer in clinical trials. Participants' narratives about their decision-making provide an insight into how international bioethical debates interact with, but may also stand apart from, the situated social and economic realities driving decision-making around clinical trials on the ground. This highlights the need for ethical approaches that foreground the political, social, and economic context.


Assuntos
Ebolavirus , Epidemias , Doença pelo Vírus Ebola , Humanos , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/epidemiologia , República Democrática do Congo/epidemiologia , Surtos de Doenças/prevenção & controle
14.
Ann N Y Acad Sci ; 1518(1): 209-225, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36183296

RESUMO

The COVID-19 pandemic caught the world largely unprepared, including scientific and policy communities. On April 10-13, 2022, researchers across academia, industry, government, and nonprofit organizations met at the Keystone symposium "Lessons from the Pandemic: Responding to Emerging Zoonotic Viral Diseases" to discuss the successes and challenges of the COVID-19 pandemic and what lessons can be applied moving forward. Speakers focused on experiences not only from the COVID-19 pandemic but also from outbreaks of other pathogens, including the Ebola virus, Lassa virus, and Nipah virus. A general consensus was that investments made during the COVID-19 pandemic in infrastructure, collaborations, laboratory and manufacturing capacity, diagnostics, clinical trial networks, and regulatory enhancements-notably, in low-to-middle income countries-must be maintained and strengthened to enable quick, concerted responses to future threats, especially to zoonotic pathogens.


Assuntos
COVID-19 , Ebolavirus , Humanos , Pandemias , COVID-19/epidemiologia , Surtos de Doenças
16.
BMJ Open ; 12(3): e055596, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260458

RESUMO

INTRODUCTION: Ebola virus disease (EVD) continues to be a significant public health problem in sub-Saharan Africa, especially in the Democratic Republic of the Congo (DRC). Large-scale vaccination during outbreaks may reduce virus transmission. We established a large population-based clinical trial of a heterologous, two-dose prophylactic vaccine during an outbreak in eastern DRC to determine vaccine effectiveness. METHODS AND ANALYSIS: This open-label, non-randomised, population-based trial enrolled eligible adults and children aged 1 year and above. Participants were offered the two-dose candidate EVD vaccine regimen VAC52150 (Ad26.ZEBOV, Modified Vaccinia Ankara (MVA)-BN-Filo), with the doses being given 56 days apart. After vaccination, serious adverse events (SAEs) were passively recorded until 1 month post dose 2. 1000 safety subset participants were telephoned at 1 month post dose 2 to collect SAEs. 500 pregnancy subset participants were contacted to collect SAEs at D7 and D21 post dose 1 and at D7, 1 month, 3 months and 6 months post dose 2, unless delivery was before these time points. The first 100 infants born to these women were given a clinical examination 3 months post delivery. Due to COVID-19 and temporary suspension of dose 2 vaccinations, at least 50 paediatric and 50 adult participants were enrolled into an immunogenicity subset to examine immune responses following a delayed second dose. Samples collected predose 2 and at 21 days post dose 2 will be tested using the Ebola viruses glycoprotein Filovirus Animal Non-Clinical Group ELISA. For qualitative research, in-depth interviews and focus group discussions were being conducted with participants or parents/care providers of paediatric participants. ETHICS AND DISSEMINATION: Approved by Comité National d'Ethique et de la Santé du Ministère de la santé de RDC, Comité d'Ethique de l'Ecole de Santé Publique de l'Université de Kinshasa, the LSHTM Ethics Committee and the MSF Ethics Review Board. Findings will be presented to stakeholders and conferences. Study data will be made available for open access. TRIAL REGISTRATION NUMBER: NCT04152486.


Assuntos
Vacinas contra Ebola , Doença pelo Vírus Ebola , Adulto , COVID-19 , Criança , Ensaios Clínicos Fase III como Assunto , República Democrática do Congo/epidemiologia , Vacinas contra Ebola/efeitos adversos , Feminino , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Esquemas de Imunização
17.
PLoS Negl Trop Dis ; 16(1): e0010089, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34990453

RESUMO

BACKGROUND: Only one recommendation currently exists for the treatment of Lassa fever (LF), which is ribavirin administered in conjunction with supportive care. This recommendation is primarily based on evidence generated from a single clinical trial that was conducted more than 30 years ago-the methodology and results of which have recently come under scrutiny. The requirement for novel therapeutics and reassessment of ribavirin is therefore urgent. However, a significant amount of work now needs to be undertaken to ensure that future trials for LF can be conducted consistently and reliably to facilitate the efficient generation of evidence. METHODOLOGY: We convened a consultation group to establish the position of clinicians and researchers on the core components of future trials. A Core Eligibility Criteria (CEC), Core Case Definition (CCD), Core Outcome Set (COS) and Core Data Variables (CDV) were developed through the process of a multi-stakeholder consultation that took place using a modified-Delphi methodology. RESULTS: A consensus position was achieved for each aspect of the framework, which accounts for the inclusion of pregnant women and children in future LF clinical trials. The framework consists of 8 core criteria, as well as additional considerations for trial protocols. CONCLUSIONS: This project represents the first step towards delineating the clinical development pathway for new Lassa fever therapeutics, following a period of 40 years without advancement. Future planned projects will bolster the work initiated here to continue the advancement of LF clinical research through a regionally-centred, collaborative methodology, with the aim of delineating a clear pathway through which LF clinical trials can progress efficiently and ensure sustainable investments are made in research capacity at a regional level.


Assuntos
Antivirais/farmacologia , Ensaios Clínicos Fase III como Assunto/métodos , Desenvolvimento de Medicamentos/métodos , Febre Lassa/tratamento farmacológico , Descoberta de Drogas/métodos , Humanos , Vírus Lassa/efeitos dos fármacos , Projetos de Pesquisa , Inquéritos e Questionários
18.
PLOS Glob Public Health ; 2(8): e0000246, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36962712

RESUMO

The Joint External Evaluation (JEE) assesses national capacities to implement the International Health Regulations (IHR). Previous studies have found that higher JEE scores are associated with fewer communicable disease deaths. But given the impact of COVID-19 in many countries, including those believed to have developed IHR capacities, the validity of the JEE for pandemic preparedness has been questioned. We constructed univariable and multivariable linear regression models to investigate the relationship between JEE scores and i) deaths from communicable diseases before the pandemic and ii) deaths from COVID-19. We adjusted for country differences in age, health system access, national wealth, health expenditure, democratic governance, government restrictions, pre-pandemic tourist arrivals and testing capacity (estimated by test positivity rates). For COVID-19 deaths, we calculated cumulative deaths per 100,000 at 3, 6 and 12 months into the pandemic. A total of 91 countries were included, with a median JEE score of 50%. On multivariable linear regression the association between JEE scores and log COVID-19 deaths was significant and positive at 3 months (ß 0.05, p = 0.02), becoming statistically non-significant, at 6 (ß 0.02, p = 0.27) and 12 months (ß -0.03, p = 0.19), while the association with log communicable disease deaths was significant and negative (ß -0.03, p = 0.003). A higher Stringency Index was significantly associated with higher log COVID-19 deaths at 3 (ß 0.04, p = 0.003) and 6 (ß 0.04, p = 0.001) months, but not at 12 months (ß 0.02, p = 0.08). Higher test positivity rates were associated with higher log COVID-19 deaths at all time points, at least partially attenuating the positive association between Stringency Index and log COVID-19 deaths. While universal health coverage indices (ß -0.04 p<0.001) and international tourist arrivals were associated with log communicable disease deaths (ß 0.02, p = 0.002), they were not associated with log COVID-19 deaths. Although the same tool is used to assess capacities for both epidemics and pandemics, the JEE may be better suited to small outbreaks of known diseases, compared to pandemics of unknown pathogens.

19.
BMJ Glob Health ; 6(9)2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34535490

RESUMO

INTRODUCTION: COVID-19 vaccines are now being distributed to low- and middle-income countries (LMICs), with global urgency surrounding national vaccination plans. LMICs have significant experience implementing vaccination campaigns to respond to epidemic threats but are often hindered by chronic health system challenges. We sought to identify transferable lessons for COVID-19 vaccination from the rollout of three vaccines that targeted adult groups in Africa and South America: MenAfriVac (meningitis A); 17D (yellow fever) and rVSV-ZEBOV (Ebola virus disease). METHODS: We conducted a rapid literature review and 24 semi-structured interviews with technical experts who had direct implementation experience with the selected vaccines in Africa and South America. We identified barriers, enablers, and key lessons from the literature and from participants' experiences. Interview data were analysed thematically according to seven implementation domains. RESULTS: Participants highlighted multiple components of vaccination campaigns that are instrumental for achieving high coverage. Community engagement is an essential and effective tool, requiring dedicated time, funding and workforce. Involving local health workers is a key enabler, as is collaborating with community leaders to map social groups and tailor vaccination strategies to their needs. Vaccination team recruitment and training strategies need to be enhanced to support vaccination campaigns. Although recognised as challenging, integrating vaccination campaigns with other routine health services can be highly beneficial if well planned and coordinated across health programmes and with communities. CONCLUSION: As supplies of COVID-19 vaccines become available to LMICs, countries need to prepare to efficiently roll out the vaccine, encourage uptake among eligible groups and respond to potential community concerns. Lessons from the implementation of these three vaccines that targeted adults in LMICs can be used to inform best practice for COVID-19 and other epidemic vaccination campaigns.


Assuntos
COVID-19 , Vacinas contra Ebola , Doença pelo Vírus Ebola , Meningite , Febre Amarela , Adulto , Vacinas contra COVID-19 , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Programas de Imunização , SARS-CoV-2 , Febre Amarela/epidemiologia , Febre Amarela/prevenção & controle
20.
Curr Opin Infect Dis ; 34(5): 393-400, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34342301

RESUMO

PURPOSE OF REVIEW: The COVID-19 pandemic is a global catastrophe that has led to untold suffering and death. Many previously identified policy challenges in planning for large epidemics and pandemics have been brought to the fore, and new ones have emerged. Here, we review key policy challenges and lessons learned from the COVID-19 pandemic in order to be better prepared for the future. RECENT FINDINGS: The most important challenges facing policymakers include financing outbreak preparedness and response in a complex political environment with limited resources, coordinating response efforts among a growing and diverse range of national and international actors, accurately assessing national outbreak preparedness, addressing the shortfall in the global health workforce, building surge capacity of both human and material resources, balancing investments in public health and curative services, building capacity for outbreak-related research and development, and reinforcing measures for infection prevention and control. SUMMARY: In recent years, numerous epidemics and pandemics have caused not only considerable loss of life, but billions of dollars of economic loss. The COVID-19 pandemic served as a wake-up call and led to the implementation of relevant policies and countermeasures. Nevertheless, many questions remain and much work to be done. Wise policies and approaches for outbreak control exist but will require the political will to implement them.


Assuntos
COVID-19/prevenção & controle , Epidemias/legislação & jurisprudência , Epidemias/prevenção & controle , Pandemias/legislação & jurisprudência , Pandemias/prevenção & controle , Animais , Surtos de Doenças/legislação & jurisprudência , Surtos de Doenças/prevenção & controle , Saúde Global/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Mão de Obra em Saúde/legislação & jurisprudência , Humanos , Saúde Pública/legislação & jurisprudência
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