Reemergence of Marburgvirus disease: Update on current control and prevention measures and review of the literature

Therapeutic advances in Marburg virus disease: from experimental treatments to vaccine development

The Marburg virus (MARV), discovered in 1967, has led to devastating outbreaks over the world; the mortality rate of Marburg virus disease (MVD) varies according to the outbreak and viral type. The very first known filovirus hemorrhagic fever outbreaks occurred in Germany and the former Yugoslavia. MVD is a deadly illness caused by the MARV virus, part of the Filoviridae family. It progresses with early viral replication that damages immune cells, followed by destruction of organs like the spleen, liver, and lymphoid tissues. Combatting this disease requires proper health education, and strong strategies. MVD is a lethal single-stranded RNA virus transmitted by Egyptian rousette bats, with a fatality rate of approximately 90%. This work explored ongoing studies on the recent vaccine developments and experimental therapies, such as a recombinant vesicular stomatitis virus (VSV)-based vaccine and MVA-BN-Filo, aiming to combat this deadly infection. Over the previous years, MARV has also spread to non-endemic African countries, demonstrating its potential to cause epidemics. Although MARV-specific vaccines are evaluated in preclinical and clinical research, none have been approved for human use. Studies revealed that Modified Vaccinia virus Ankara, a well-established viral vector used to generate vaccines against emerging pathogens, can deliver multiple antigens and has a remarkable clinical safety and immunogenicity record. MVD has been recently reported in Rwanda in 2024, an African country, and nearly 15 outbreaks of MVD have been reported. This review describes the nature of the MVD, key outbreaks, the virus's pathogenesis, mode of transmission, clinical and laboratory diagnosis, and control and prevention measures to advance MVD treatment, drug development, vaccine creation, and prevention of MVD.

Improving risk analysis of the environmental drivers of the spillover, emergence/re-emergence and spread of Crimean-Congo haemorrhagic fever virus, Marburg virus and Middle East respiratory syndrome coronavirus in the East Africa Region

INTRODUCTION

Emerging and/or re-emerging infectious diseases (EIDs) in the East Africa region are associated with climate change-induced environmental drivers. There is a need for a comprehensive understanding of these environmental drivers and to adopt an integrated risk analysis (IRA) framework for addressing a combination of the biological, environmental and socioeconomic factors that increase population vulnerabilities to EID risks to inform biological risk mitigation and cross-sectoral decision-making. The aim of this integrative review was to identify knowledge gaps and contribute to a holistic understanding about the environmental drivers of Crimean-Congo haemorrhagic fever virus (CCHFV), Marburg virus (MARV) and Middle East respiratory syndrome coronavirus (MERS-CoV) infections in the East Africa Region to improve IRA processes at the environment-animal-human exposure interface.

METHODS

An integrative review search was carried out to identify relevant studies and reports from 2000 to 2024. Searches were conducted in bibliographic databases and global institutional websites. Inclusion criteria were studies and reports (in English) addressing environmental drivers of CCHFV, MARV and MERS-CoV infections across countries in the East Africa region, existing risk frameworks/methodological tools and/or One Health policy recommendations for risk analysis of environmentally driven biological threats.

RESULTS

Of the total number of studies retrieved from database searches (n=18 075) and website searches (n=44), 242 studies and reports combined were included in the review with the majority covering the environmental drivers (n=137), the risk frameworks/methodological tools (n=73) and the policy recommendations (n=32). We identified 10 categories of environmental drivers, four thematic groups of risk frameworks and three categories of policy recommendations. Overall, many of the included records on the risk frameworks/methodological tools expounded on the adoption of ecological niche modelling (ENM) for environmental monitoring of potential transmission pathways of EIDs and other biological threats.

CONCLUSION

This integrative review recommends the adoption of specialised risk mapping approaches such as ENM for environmental monitoring of EIDs under IRA processes. Findings from the review were used for the conceptualisation of an IRA framework for addressing environmentally driven EIDs.

Mapping knowledge landscapes and emerging trends of Marburg virus: A text-mining study

Background

Marburg virus (MARV), a close relative of Ebola virus, could induce hemorrhagic fevers in humans with high mortality rate. In recent years, increasing attention has been paid to this highly lethal virus due to sporadic outbreaks observed in various African nations. This bibliometric analysis endeavors to elucidate the trends, dynamics, and focal points of knowledge that have delineated the landscape of research concerning MARV.

Methods

Relevant literature on MARV from 1968 to 2023 was extracted from the Web of Science Core Collection database. Following this, the data underwent bibliometric analysis and visualization procedures utilizing online analysis platform, CiteSpace 6.2R6, and VOSviewer 1.6.20. Three different types of bibliometric indicators including quantitative indicator, qualitative indicators, and structural indicators were used to gauge a researcher's productivity, assess the quality of their work, and analyze publication relationships, respectively.

Results

MARV is mainly prevalent in Africa. And approximately 643 confirmed cases have been described in the literature to date, and mortality observed was 81.2 % in overall patients. A total of 1014 papers comprising 869 articles and 145 reviews were included. The annual publications showed an increasing growth pattern from 1968 to 2023 (R2 = 0.8838). The United States stands at the forefront of this discipline, having dedicated substantial financial and human resources to scientific inquiry. However, co-authorship analysis showed the international research collaboration needs to be further strengthened. Based on reference and keywords analysis, contemporary MARV research encompasses pivotal areas: primarily, prioritizing the creation of prophylactic vaccines to impede viral spread, and secondarily, exploring targeted antiviral strategies, including small-molecule antivirals or MARV-specific monoclonal antibodies. Additionally, a comprehensive grasp of viral transmission, transcription, and replication mechanisms remains a central focus in ongoing investigations. And future MARV studies are expected to focus on evaluating clinical trial safety and efficacy, developing inhibitors to contain viral spread, exploring vaccine immunogenicity, virus-host association studies, and elucidating the role of neutralizing antibodies in MARV treatment.

Conclusion

The present study offered comprehensive insights into the contemporary status and trajectories of MARV over the past decades. This enables researchers to discern novel collaborative prospects, institutional partnerships, emerging topics, and research forefronts within this domain.

Emergence of Marburg virus: a global perspective on fatal outbreaks and clinical challenges

The Marburg virus (MV), identified in 1967, has caused deadly outbreaks worldwide, the mortality rate of Marburg virus disease (MVD) varies depending on the outbreak and virus strain, but the average case fatality rate is around 50%. However, case fatality rates have varied from 24 to 88% in past outbreaks depending on virus strain and case management. Designated a priority pathogen by the National Institute of Allergy and Infectious Diseases (NIAID), MV induces hemorrhagic fever, organ failure, and coagulation issues in both humans and non-human primates. This review presents an extensive exploration of MVD outbreak evolution, virus structure, and genome, as well as the sources and transmission routes of MV, including human-to-human spread and involvement of natural hosts such as the Egyptian fruit bat (Rousettus aegyptiacus) and other Chiroptera species. The disease progression involves early viral replication impacting immune cells like monocytes, macrophages, and dendritic cells, followed by damage to the spleen, liver, and secondary lymphoid organs. Subsequent spread occurs to hepatocytes, endothelial cells, fibroblasts, and epithelial cells. MV can evade host immune response by inhibiting interferon type I (IFN-1) synthesis. This comprehensive investigation aims to enhance understanding of pathophysiology, cellular tropism, and injury sites in the host, aiding insights into MVD causes. Clinical data and treatments are discussed, albeit current methods to halt MVD outbreaks remain elusive. By elucidating MV infection's history and mechanisms, this review seeks to advance MV disease treatment, drug development, and vaccine creation. The World Health Organization (WHO) considers MV a high-concern filovirus causing severe and fatal hemorrhagic fever, with a death rate ranging from 24 to 88%. The virus often spreads through contact with infected individuals, originating from animals. Visitors to bat habitats like caves or mines face higher risk. We tailored this search strategy for four databases: Scopus, Web of Science, Google Scholar, and PubMed. we primarily utilized search terms such as "Marburg virus," "Epidemiology," "Vaccine," "Outbreak," and "Transmission." To enhance comprehension of the virus and associated disease, this summary offers a comprehensive overview of MV outbreaks, pathophysiology, and management strategies. Continued research and learning hold promise for preventing and controlling future MVD outbreaks. GRAPHICAL ABSTRACT.

Preparing for future outbreaks in Ghana: An overview of current COVID-19, monkeypox, and Marburg disease outbreaks

Amidst the ongoing COVID-19 pandemic, Ghana is currently grappling with simultaneous outbreaks of Marburg virus disease and human monkeypox virus. The coexistence of these outbreaks emphasizes the imperative for a collaborative and global approach to enhance surveillance and expedite case detection. While Ghana has made efforts to respond to these outbreaks, this paper outlines the lessons learned and proposes recommendations in this regard. It is crucial to intensify response efforts at the local, regional, and national levels to effectively contain the spread of these infectious diseases. Therefore, this paper suggests prioritizing the following recommendations as crucial for assisting Ghana in adequately preparing for future outbreaks and safeguarding global public health: strengthening surveillance system through digitization, rapid and effective response; risk communication and community engagement; healthcare system readiness; and research and collaboration. Also, prioritizing building healthy public policies and developing personal skills of health personnel across the country is key for future outbreak response.