Rise of Marburg virus in Africa: a call for global preparedness

Ebola virus disease mathematical models and epidemiological parameters: a systematic review

Ebola virus disease poses a recurring risk to human health. We conducted a systematic review (PROSPERO CRD42023393345) of Ebola virus disease transmission models and parameters published from database inception to July 7, 2023, from PubMed and Web of Science. Two people screened each abstract and full text. Papers were extracted with a bespoke Access database, 10% were double extracted. We extracted 1280 parameters and 295 models from 522 papers. Basic reproduction number estimates were highly variable, as were effective reproduction numbers, likely reflecting spatiotemporal variability in interventions. Random-effect estimates were 15·4 days (95% CI 13·2-17·5) for the serial interval, 8·5 days (7·7-9·2) for the incubation period, 9·3 days (8·5-10·1) for the symptom-onset-to-death delay, and 13·0 days (10·4-15·7) for symptom-onset-to-recovery. Common effect estimates were similar, albeit with narrower CIs. Case-fatality ratio estimates were generally high but highly variable, which could reflect heterogeneity in underlying risk factors. Although a substantial body of literature exists on Ebola virus disease models and epidemiological parameter estimates, many of these studies focus on the west African Ebola epidemic and are primarily associated with Zaire Ebola virus, which leaves a key gap in our knowledge regarding other Ebola virus species and outbreak contexts.

Unveiling the hidden threats: a review of pathogen diversity and public health risks from bats, rodents, and non-human primates in Zambia (1990-2022)

Background

Infectious disease agents of animal origin, which can cause mild to severe illnesses in humans, are increasingly spilling over into human populations. Southern Africa, particularly Zambia as a regional transport hub, has experienced notable outbreaks of zoonotic pathogens in recent years. This context underscores the importance of research, as numerous studies over the past 33 years have reported various infectious agents with differing zoonotic potential from bats, rodents, and non-human primates (NHPs) in Zambia. However, the data remained unaggregated, hampering comprehensive and organized understanding of these threats.

Methods

A review spanning January 1990 to December 2022 synthesised data from selected studies conducted in bats, rodents, and NHPs across 14 of Zambia's 116 districts.

Results

Among the reported pathogens, viruses predominated (62%, 31/50), followed by parasites (20%, 10/50)), and bacteria (18%, 9/50). Notable pathogens included Ebola virus, Marburg virus, Hantavirus, Zika virus, Human parainfluenza virus-3, Anaplasma phagocytophilum, Borrelia faini, Coxiella burnetii, Trypanosoma brucei rhodesiense, Calodium hepaticum, and Trichinella spiralis. Most identified infectious agents came from short term cross-sectional investigations, thus, the temporal dynamics related to abundance and likelihood of outbreaks remain unknown.

Conclusion

The findings starkly illuminate significant zoonotic public health threats amidst glaring under-surveillance of zoonoses in humans in Zambia. This critical gap calls urgently for enhanced active, passive and syndromic surveillance activities to identify new diseases and provide evidence-based measures to safeguard public health from emerging infectious risks in Zambia and the Southern African sub-region, considering the country's position as a regional transport hub.

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.

The Current Pathogenicity and Potential Risk Evaluation of Marburg Virus to Cause Mysterious "Disease X"-An Update on Recent Evidences

The World Health Organization (WHO) defined Disease X as an upcoming disease with the potential to cause a pandemic. Pathogen X is responsible for Disease X. Marburg virus disease (MVD) is one of the diseases from the priority disease list published by WHO. Marburg virus is a filamentous, negative-sense RNA virus that belongs to the same filovirus family as the lethal Ebola virus. Since the first discovery of this virus in 1967, 17 outbreaks occurred sporadically till 2023. Rousettus aegyptiacus acts as the natural reservoir of the virus. With an average incubation period of 5 to 10 days, its first target is the mononuclear phagocytic system cells. It is highly contagious and can be easily transmitted from animal to human and human to human via direct contact with blood or body fluid, feces, and semen of the infected host. Although Marburg disease has a high case fatality rate of close to 90%, unfortunately, there is no approved vaccines or treatments are available. The most recent outbreak of Marburg virus in Equatorial Guinea and Tanzania in 2023 caused an alert for global health. However, based on the last global pandemic of COVID-19 and the sudden re-emerging of monkeypox around the world, we can assume that the Marburg virus has the potential to cause a global pandemic. Our modern world depends on globalization, which helps the virus transmission among countries. The Marburg virus can easily be transmitted to humans by fruit bats of the Pteropodidae family. This virus causes severe hemorrhagic disease, and there are no specific vaccines and treatments available to combat it. Therefore, community engagement and early supportive care for patients are keys to successfully controlling MVD.