Pan - #Ebolavirus nanoparticle #vaccine provides protection in rodents from lethal #infection by #Zaire and #Sudan viruses

 

Abstract

Both Zaire ebolavirus (EBOV) and Sudan ebolavirus (SUDV) are members of the genus Ebolavirus and cause outbreaks marked by high fatality rates and repeated spillover from animal reservoirs. Filoviral glycoproteins (GPs) are the primary targets of neutralizing antibodies and form the basis of current vaccines. Here we describe the design, structural characterization, and evaluation of two-component self-assembling icosahedral I53-50 nanoparticles displaying prefusion EBOV or SUDV GP antigens, either individually or in cocktail and mosaic multivalent formats. EBOV-GP-I53-50 and SUDV-GP-I53-50 nanoparticles elicited strong homologous protection in mice and guinea pigs. In the mouse-adapted EBOV model (maEBOV), mosaic and cocktail formulations produced weak survival below that of the matched EBOV-GP-I53-50 GP immunogen. In contrast, in the gpaSUDV guinea pig model (gpSUDV), cocktail and mosaic nanoparticles elicited robust protection against gpSUDV, and detectable antibody responses to both SUDV and EBOV GPs. These findings demonstrate that multivalent GP-I53-50 nanoparticle immunogens can protect rodents from death, severe clinical signs of disease, and weight loss in relevant models. Together with the established clinical safety of the I53-50 platform, these results support continued efforts toward the development of a pan-ebolavirus vaccine.

Source: 

Link: https://www.nature.com/articles/s41467-026-76114-1

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#Phylogenetic analysis of the 2025 #Ebola #outbreak in the #DRC

 

Abstract

On 4 September 2025, the Ministry of Public Health, Hygiene and Social Welfare officially declared the 16th Ebola disease outbreak in the Democratic Republic of the Congo (DRC). This outbreak ended on 1 December 2025 and occurred in Bulape Health Zone, Kasaï Province, an area with limited access to appropriate healthcare facilities and resources. Here, we describe the probable index patient and molecular investigations of samples obtained from six suspected patients from the initial outbreak phase. We identified Orthoebolavirus zairense (EBOV) in five samples from different patients. In addition, we performed whole-genome sequencing and generated four complete EBOV genomes. These genomes form a well-supported phylogenetic cluster with genomes from the 1976 Yambuku/Mayinga outbreak. This study suggests a likely new zoonotic spillover event from an as-yet unidentified natural reservoir. While the close relationship to 1976 EBOV Yambuku/Mayinga genomes is striking, this poses additional challenges on the comprehension of the animal reservoir species.

Source: 

Link: https://www.nature.com/articles/s41467-026-77542-9

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A #review of #Bundibugyo virus and the 2026 #outbreak: lessons for #epidemic #preparedness

 

Summary

The ongoing 2026 outbreak of Ebola virus disease caused by Bundibugyo virus (BDBV) in the Democratic Republic of the Congo and Uganda has renewed attention to one of the least studied human-pathogenic orthoebolaviruses. Since its discovery in western Uganda in 2007, only two recognised outbreaks of BDBV had been reported, limiting opportunities to define the epidemiology, pathogenesis, diagnosis, clinical spectrum, and optimal management of BDBV or to develop species-specific countermeasures. The current outbreak, declared a Public Health Emergency of International Concern by WHO on May 17, 2026, has also exposed the gap between scientific innovation and operational readiness. Although pan-filovirus diagnostics, investigational vaccines, therapeutics, and adaptive clinical trial platforms are now available, their deployment has been constrained by delayed diagnosis, limited access to species-inclusive diagnostics, insecurity due to conflict, population displacement, and fragile health systems. In this Review, we synthesise evidence on BDBV from its discovery to the current 2026 outbreak, highlighting advances in epidemiology, clinical management, diagnostics, vaccines, therapeutics, and preparedness. More broadly, the outbreak shows that scientific innovation alone is insufficient; its public health impact depends on integrated, species-inclusive systems capable of rapidly detecting, evaluating, and responding to outbreaks caused by any human-pathogenic Orthoebolavirus spp.

Source: 

Link: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(26)00414-7/fulltext

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#Development and Characterization of a Recombinant #Bundibugyo Virus Expressing a Fluorescent Reporter Protein

 

Abstract

Bundibugyo virus disease (BVD), caused by Bundibugyo virus (BDBV), is associated with substantial morbidity and mortality, with previous outbreaks reporting case fatality rates of 30%–50%. The ongoing BDBV outbreak in the Democratic Republic of the Congo and Uganda highlights the urgent need for virus-specific research tools and medical countermeasures. Unlike Ebola virus disease caused by Zaire ebolavirus, no licensed vaccines or specific therapeutics are currently available for BVD. The lack of research tools has limited studies with BDBV. To facilitate antiviral testing and neutralization studies, we developed the first recombinant BDBV expressing the fluorescent reporter protein ZsGreen (rBDBV-ZsG). As a proof of concept, we tested a set of previously characterized antiviral compounds and demonstrated comparable inhibitory profiles between rBDBV-ZsG and the wild-type BDBV parental strain. Furthermore, the utility of rBDBV-ZsG was successfully evaluated in neutralization assays, demonstrating robust sensitivity and specificity using monoclonal antibodies and convalescent serum samples.

Source: 

Link: https://www.tandfonline.com/doi/full/10.1080/22221751.2026.2709847

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#Filovirus #Surveillance in Communities Bordering Equatorial Guinea, #Marburg #Outbreak, #Cameroon, 2023

 

Abstract

After the 2023 Equatorial Guinea Marburg virus (MARV) outbreak, surveillance of 181 persons in southern Cameroon detected MARV antibodies in 3 persons and Ebola virus antibodies in 7. Testing of 289 captured bats, including 158 Rousettus aegyptiacus bats, did not detect MARV RNA. Enhanced surveillance for regional filovirus spillover risks is warranted.

Source: 

Link: https://wwwnc.cdc.gov/eid/article/32/8/26-0117_article

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Past #lessons for the 2026 #Bundibugyo virus #outbreak: #filovirus infection #prevention in #conflict-affected settings

 

Summary

In May 2026, the World Health Organization declared a Public Health Emergency of International Concern after Bundibugyo virus disease re-emerged in Ituri Province, Democratic Republic of the Congo, with cross-border transmission to Uganda. The suspected index case was a healthcare worker, and at least four healthcare workers had died before the outbreak was confirmed. The outbreak is unfolding in a region characterised by armed conflict, mass displacement, fragile governance and disrupted clinical infrastructure — a setting in which the high-containment infection prevention measures developed for filovirus disease in well-resourced facilities are difficult to implement reliably. In this narrative, evidence-informed review we propose an achievable infection prevention bundle for filovirus outbreaks in conflict-affected settings, framing personal protective equipment, training, supervised doffing, supply chains, staffing, environmental controls and facility organisation as interdependent components of a single coherent system rather than as alternatives. We summarise outbreak situation reports, operational documentation and simulation evidence; identify operational failure modes in austere conditions; and propose an eight-element bundle prioritised by implementation urgency. The bundle is anchored in WHO core IPC programme guidance. Most of the available evidence base is filovirus-general or Zaire ebolavirus-derived; extrapolation to Bundibugyo virus is reasonable but limited, and the bundle should be understood as a framework for decision-making rather than as a validated intervention package.

Source: Journal of Hospital Infection, https://www.journalofhospitalinfection.com/

Link: https://www.journalofhospitalinfection.com/article/S0195-6701(26)00266-5/abstract

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#Sudan virus disease in #humans

 

Summary

In 2025, Uganda had Africa’s ninth outbreak of disease caused by Sudan virus (SUDV), a filovirus similar to Ebola virus (EBOV) that causes severe febrile disease in humans. In this Review, we summarise the evidence on the epidemiology, natural history, and immunology of Sudan virus disease (SVD) from outbreaks since 1976. Following an incubation period averaging about 1 week, SVD typically presents with an influenza-like illness followed by a severe diarrhoeal disease, often accompanied by cardiorespiratory symptoms and dehydration. Clinical findings can include kidney and liver injury, acute inflammation, and coagulopathy. Severe cases can progress rapidly to shock, multiorgan failure, and death. The pooled case-fatality rate until 2022 was 49% (95% CI 39–58), although a lower case-fatality rate of 29% was recorded during the 2025 outbreak. The virus is detectable in blood from symptom onset, peaking during acute illness. Transmission occurs mainly through close contact with acutely symptomatic individuals and their body fluids, driving household and nosocomial spread. Early T-cell responses and SUDV-specific antibodies might be important for survival, and suppressed immunity and uncontrolled inflammation might predict fatal outcomes. Survivors present durable humoral and cellular immunity for up to 15 years after infection. Although outbreaks to date offer valuable insights into SVD, substantial evidence gaps and limitations exist. Future outbreak preparedness should include prospective planning for high-quality research that can be rapidly implemented to address key evidence gaps. Strengthening these data, together with advancing the development and evaluation of vaccines and therapeutics, will be essential for timely and effective outbreak response.

Source: The Lancet Global Health, https://www.thelancet.com/journals/langlo/home

Link: https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(26)00072-0/fulltext

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#WHO issues comprehensive #guidelines on #filovirus disease, including #Ebola and #Marburg disease (June 17 '26)

 

    As the Democratic Republic of the Congo is battling an Ebola disease outbreak caused by the Bundibugyo virus, the World Health Organization (WHO) has released its first comprehensive guidelines for the clinical management of filovirus disease which include all types of Ebola and Marburg viruses. 

    The new guidelines highlight the importance of early supportive care to improve patient survival and health outcomes, outlining 16 evidence-based recommendations.

    Ebola and Marburg diseases are serious and often fatal, with case fatality rates ranging from 25% to 90% in the most severe outbreaks. 

    There have been 72 outbreaks of Ebola and Marburg diseases reported in Africa since 1967, when Marburg virus was first discovered. 

    These outbreaks often have significant socio-economic and psychological impact on communities affected. 

    In the absence of licensed vaccines and treatments for Marburg virus disease, Bundibugyo and Sudan virus diseases, early supportive care significantly improves survival.

    “These new guidelines are a perfect example of how WHO leverages science to better protect and care for people during outbreaks and health emergencies,” WHO Director-General Dr Tedros Adhanom Ghebreyesus says. 

    “The current Bundibugyo virus outbreak is a stark reminder of the need for diligent, holistic and person-focused medical care, to save lives and preserve human dignity. We encourage governments and authorities to integrate these new recommendations into preparedness and outbreak response, to ensure high-quality care for everyone.”

    Developed through global expert consultations and based on the most up-to-date scientific evidence and clinical knowledge, the guidelines translate lessons learned from recent Ebola and Marburg disease outbreaks into practical recommendations for improved patient care. 

    WHO has previously issued several guidelines on clinical care and therapeutics specific to Ebola virus disease.

    The new guidelines have been developed primarily to guide health workers when caring for patients, to harmonize clinical approaches, and enable health facility administrators and policy makers to better plan, prepare for and respond to filovirus disease outbreaks through adequate provision of medical supplies, biomedical equipment, laboratory support, and human resources.

    The practical recommendations aim to support frontline health workers in identifying clinical deterioration, managing dehydration and shock, improving patient monitoring, delivering critical supportive interventions safely, and providing structured follow-up for patients who recovered from Ebola and Marburg diseases. 

    Some of the key recommendations include:

        ° Using prioritized clinical laboratory tests to monitor patients with filovirus disease, to identify and manage treatable problems (such as hypoglycaemia, metabolic disruptions);

        ° Quickly and accurately treating dehydration in patients with filovirus disease using oral and intravenous rehydration;

        ° Promoting early and precise use of intravenous fluids and vasoactive medications to treat shock in patients with filovirus disease (low blood pressure caused by the infection, which if not properly addressed leads to organ failure), guided by serial monitoring of vital signs and markers of perfusion;

        ° Ensuring that if other bacterial infections, including bacterial sepsis, are present in patients with filovirus disease, appropriate treatment with antibiotics is initiated;

        ° Providing structured after-care to patients who have survived filovirus disease to promote well-being, and to prevent further infections linked to viral persistence in people who recovered from the disease.

    For Bundibugyo virus disease, as with other filovirus diseases, early recognition, rapid referral and optimized supportive care remain fundamental components of patient care. 

    Optimized supportive care can reduce complications and provide the foundation on which all other clinical interventions are delivered. 

    It is also a pre-requisite for clinical research evaluating antiviral treatments. These clinical guidelines complement existing WHO guidance and operational tools designed to support safe and effective care delivery.

About WHO

    Dedicated to the well-being of all people and guided by science, the World Health Organization leads and champions global efforts to give everyone, everywhere an equal chance at a safe and healthy life.

    We are the UN agency for health that connects nations, partners and people on the front lines in 150+ locations – leading the world’s response to health emergencies, preventing disease, addressing the root causes of health issues and expanding access to medicines and health care. Our mission is to promote health, keep the world safe and serve the vulnerable.

    “Together for health. Stand with science”, the theme of World Health Day 2026 marks a year-long campaign to highlight science as the foundation for protecting health and well-being worldwide.

Source: 

Link: https://www.who.int/news/item/17-06-2026-who-issues-comprehensive-guidelines-on-filovirus-disease--including-ebola-and-marburg-disease

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Regional #Signals Preceding the 2026 #Bundibugyo Virus Disease #Outbreak

 

Highlights

    • Bundibugyo virus circulated undetected for months prior to outbreak declaration.

    • Four earlier regional hemorrhagic fever clusters flagged by open surveillance are unresolved.

    • These clusters warrant urgent reanalysis due to concern for regional spread.

Abstract

Background

The May 2026 Bundibugyo virus disease (BVD) outbreak in the Democratic Republic of the Congo was declared a Public Health Emergency of International Concern after substantial undetected community transmission. We describe regional surveillance signals detected by the Biothreats Emergence, Analysis, and Communications Network (BEACON), our open access event based surveillance program, in the weeks preceding outbreak declaration.

Methods

We reviewed BEACON reports of VHF-compatible illness clusters detected in the transboundary DRC-Uganda-Burundi-South Sudan region during March–April 2026, prior to the May 15 laboratory confirmation of BDBV.

Results

BEACON detected four temporally proximal VHF-compatible illness signals: (1) March 9, North Kivu Province—suspected Ebola case under investigation with unresolved laboratory results; (2) March 10, Kasaï Province—fatal hemorrhagic illness with secondary cases and negative Ebola PCR; (3) March 30, Burundi—35-case undiagnosed cluster near the DRC border with 5 deaths, negative testing for major filoviruses and >200 pathogens, pending metagenomic sequencing; (4) April 22, South Sudan—three suspected VHF cases with negative initial testing. All four signals shared a similar diagnostic phenotype: VHF-compatible presentation, mobilization of investigation teams, negative initial testing, and no publicly reported confirmed etiology. None were formally reported to have been resolved.

Conclusions

Our detection of four unresolved VHF signals preceding the confirmed BDBV outbreak highlights gaps in formal follow-up mechanisms for negative cases and fragmented regional diagnostic coordination. In light of confirmed BDBV circulation and Africa CDC's identification of 10 countries at high risk for spread, these preceding signals warrant urgent retrospective investigation and laboratory.

Source: 

Link: https://www.ijidonline.com/article/S1201-9712(26)00497-2/fulltext

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Cryo-EM structures of #Měnglà virus GP reveal combined #Ebola- and #Marburg-like epitope masking strategies for #antibody evasion

 

Abstract

Ebola virus (EBOV) and Marburg virus (MARV) are highly lethal filoviruses that cause severe hemorrhagic fever in humans. A recently identified bat-borne filovirus, Měnglà virus (MLAV), uses the same NPC1 receptor as EBOV and MARV, raising concerns about its potential cross-species transmission. Here, we report cryo-EM structures of the MLAV surface glycoprotein (GP) in its unbound form and in complex with the MARV-neutralizing antibody MR191. MLAV GP exhibits distinctive structural features in the Wing and heptad repeat 1D (HR1D) regions, retains a visible Cap structure even after protease treatment, and contains a MARV GP-like α2 helix. MR191, a broadly neutralizing marburgvirus antibody that targets the conserved NPC1 receptor-binding pocket in MLAV GP, nonetheless exhibits impaired neutralizing activity, likely due to shielding by the MLAV Cap. In addition, the MLAV mucin-like domain, α2 helix, and HR1A region hinder binding by representative broadly neutralizing ebolavirus antibodies targeting the GP-waist, including 6D6, CA45, ADI-15878, and ADI-15946. Together, these results provide the first structural insights into MLAV GP and identify immune evasion driven by structural and sequence divergence as a major challenge for pan-filovirus antibody development.

Source: 

Link: https://www.pnas.org/doi/abs/10.1073/pnas.2529436123?af=R

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#Africa #CDC Calls for Urgent Regional Coordination Following #Ebola Virus Disease #Outbreak in #Ituri Province, #DRC, and Imported Ebola #Bundibugyo Case Reported by #Uganda (May 16 '26)

 

    Addis Ababa, Ethiopia / Kinshasa, Democratic Republic of the Congo / Kampala, Uganda, 15 May 2026 — The Africa Centres for Disease Control and Prevention (Africa CDC) is closely monitoring the confirmed Ebola Virus Disease outbreak in Ituri Province, Democratic Republic of the Congo (DRC), and the imported Ebola Bundibugyo case reported by the Uganda Ministry of Health. 

    Africa CDC is working with national authorities and partners to support a rapid, coordinated regional response aimed at interrupting transmission, protecting communities and reducing the risk of cross-border spread.

    Following consultations with the DRC Ministry of Health and national public health institutions, preliminary laboratory results from the Institut National de Recherche Biomedicale (INRB) detected Ebola virus in 13 of 20 samples tested with the Bundibugyo Virus.

    As of the latest update from DRC, approximately 246 suspected cases and 65 deaths have been reported, mainly in Mongwalu and Rwampara health zones. 

    Four deaths have been reported among laboratory-confirmed cases. 

    Suspected cases have also been reported in Bunia and are pending confirmation. 

    These figures remain provisional and are being validated through laboratory confirmation, line-list harmonization, contact identification and epidemiological investigation.

    In a statement issued on 15 May 2026, Uganda’s Ministry of Health reported a confirmed Ebola Bundibugyo Virus Disease case in a 59-year-old Congolese male who was admitted to Kibuli Muslim Hospital on 11 May 2026 and died on 14 May 2026. 

    Uganda has reported the case as imported from DRC and has indicated that no local case has yet been confirmed. 

    Africa CDC is supporting coordination to align laboratory information, contact management and cross-border risk assessment across affected and at-risk settings.

    The confirmation of an imported case reported by Uganda underscores the importance of rapid regional coordination. 

    Africa CDC remains concerned by the urban context of Bunia and Rwampara, with insecurity intense population movement, mining-related mobility in Mongwalu, gaps in contact listing, infection prevention and control challenges, and the proximity of affected areas to Uganda and South Sudan.

    Due to the cabinet meeting in DRC to discuss this outbreak, Africa CDC agreed to postpone the meeting that was planned and convene this urgent high-level regional coordination meeting today 16 May 2026 with health authorities from DRC, Uganda and South Sudan, together with the WHO, UNICEF, the Pandemic Fund, African Medicines Agency (AMA), U.S. CDC and other response partners. 

    The meeting will focus on immediate response priorities, cross-border surveillance and alert management, laboratory support and sequencing, infection prevention and control, case management, risk communication and community engagement, safe and dignified burials, contact management, logistics and resource mobilization.

    “Africa CDC stands in solidarity with the Governments and people of the Democratic Republic of the Congo and Uganda as they respond to this outbreak,” said H.E. Dr Jean Kaseya, Director General of Africa CDC. 

    “The situation requires speed, scientific rigour and regional solidarity. We are working with DRC, Uganda, South Sudan and partners to strengthen surveillance, preparedness and response, and to help contain transmission as quickly as possible.”

    To respond in a more coherent and holistic way to this regional outbreak, Africa CDC took the following immediate actions:

        ° Activate the Incident management Support Team (IMST) including all partners as the regional coordinating mechanism for the 3 countries and approve a 72-hour Incident Action Plan covering DRC and Uganda responses and South Sudan preparedness.

        ° Deploy multidisciplinary surge teams to support DRC and Uganda where the disease is cleared, with parallel readiness support for neighboring countries.

        ° Establish a medical countermeasures workstream to assess diagnostics, PPE, therapeutics, vaccines and cold chain needs, pending final sequencing.

        ° Mandate the Science, Innovation and R&D team, to coordinate sequencing follow-up, evidence review, product options, research protocols and partner engagement.

        ° Convene the regional partner coordination meeting on 16 May at 3pm Geneva time with DRC, Uganda, South Sudan, WHO, AMA and key technical and financing partners,

        ° Hold an evening press briefing on 16 May at 6pm Geneva time to brief the media on this outbreak

        ° Escalate political engagement through President Ramaphosa as the AU PPPR Champion, the AU Commission Chairperson and AU Bureau to secure high-level support for access and coordination.

    Africa CDC urges communities in affected and at-risk areas to follow guidance from national health authorities, report symptoms promptly, avoid direct physical contact with suspected cases, avoid contact with body fluids or contaminated materials, maintain hand hygiene, and support response teams working to protect communities. 

    Health facilities and health workers should maintain a high index of suspicion, apply infection prevention and control measures, and immediately report suspected cases through national reporting channels.

    Ebola Virus Disease is a severe and often fatal illness. It spreads through direct contact with the bodily fluids of infected persons, contaminated materials, or the bodies of persons who have died from the disease. Early detection, prompt isolation and care, contact tracing, infection prevention and control, community engagement, and safe and dignified burials are critical to stopping transmission.

    Africa CDC will continue to provide updates as additional information becomes available, including sequencing results, updates from national health authorities and outcomes of the regional coordination meeting.

###

About Africa CDC

    The Africa Centres for Disease Control and Prevention (Africa CDC) is the public health agency of the African Union. As an autonomous institution, Africa CDC supports AU Member States to strengthen health systems, improve disease surveillance, and enhance emergency preparedness and response. For more information, visit: http://www.africacdc.org and follow Africa CDC on LinkedIn, X, Facebook, and YouTube.

Media Contact: Wilson Johwa, Senior Communications Officer, Directorate of Communication & Public Information | JohwaW@africacdc.org

Source: 

Link: https://africacdc.org/news-item/africa-cdc-calls-for-urgent-regional-coordination-following-ebola-virus-disease-outbreak-in-ituri-province-drc-and-imported-ebola-bundibugyo-case-reported-by-uganda/

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#DRC confirms new #Ebola #outbreak, #WHO scales up support (#WHO Regional Office for Africa, May 15 '26)

 

    Kinshasa/Brazzaville — The World Health Organization (WHO) is rapidly scaling up support to the Government of the Democratic Republic of the Congo following confirmation of an outbreak of Ebola Bundibugyo in the country’s north-eastern Ituri Province.  

    Laboratory analysis conducted by the National Institute of Biomedical Research (INRB), the country’s reference laboratory in the capital Kinshasa, confirmed the Ebola outbreak caused by the Bundibugyo species in 13 of 20 samples collected from suspected cases linked to a cluster of severe illness and deaths reported in  Mongbwalu  and  Rwampara health zones in Ituri  Province.

     The Bundibugyo species was first identified in 2007 in Bundibugyo district in western Uganda, during which 131 cases were reported with 42 deaths (case fatality rate of 32%).  

    In the current outbreak in the Democratic Republic of the Congo, a total of 67 community deaths suspected to be due to Ebola Bundibugyo have been reported so far. 

    Patients presented with symptoms including fever, generalized body pain, weakness, vomiting and, in some cases, bleeding. 

    Several cases deteriorated rapidly and died. 

    Given the uncertainties and severity of the illness, there is  concern about the scale of transmission in affected communities.  

    A WHO mission including the WHO representative, the emergency preparedness and response team had already been deployed in Ituri  to support the provincial authorities with investigations that led to the confirmation of the outbreak in the two health zones.

     The team is also working with the national and provincial health authorities to strengthen outbreak control measures and prevent further spread of the virus.

     National authorities have activated emergency coordination mechanisms and deployed additional multidisciplinary rapid response teams to affected areas.  

    Additional WHO experts in epidemiology, infection prevention and control, laboratory diagnostics, clinical care, logistics, risk communication and community engagement are being mobilized to reinforce the frontline response. 

    Priority actions include strengthening disease surveillance, active case finding, contact tracing, infection prevention and control in health facilities, expanding access to safe care, laboratory testing capacity, ensuring safe burials and community sensitization to prevent further spread of the disease.    

    “The Democratic Republic of the Congo has extensive experience responding to Ebola outbreaks, and WHO is rapidly scaling up support to the ongoing response,” said Dr Mohamed Janabi, WHO Regional Director for Africa. 

    "Working closely with national authorities and partners, we are mobilizing swiftly, deploying additional expertise and resources to halt the spread of the virus, protect and save lives.”  

    WHO is airlifting 5 metric tonnes of supplies, including infection prevention and control, materials, laboratory sample transportation equipment, case management, tents and other supplies currently available in Kinshasa to Bunia to support frontline health workers and treatment facilities.    

    The outbreak is affecting areas that present significant operational challenges, including urban areas with intense population movements associated with mining activities, insecurity, and frequent cross- border movement—all of which increase the risk of further transmission.  

    In neighbouring Uganda, the Ministry of Health confirmed Ebola Bundibugyo in a patient from the Democratic Republic of the Congo who was being treated at a health facility but later died. 

    Ugandan health authorities have activated outbreak control measures, including disease surveillance, screening and response readiness.  

    This marks the 17th recorded outbreak of Ebola disease in the Democratic Republic of the Congo since the virus was first identified in 1976 in Yambuku, in Equateur Province. 

    The last one was an outbreak of Ebola virus disease that ended in December 2025.  

    Ebola disease is a severe and often fatal illness transmitted through direct contact with the blood, secretions, organs or other bodily fluids of infected people, as well as contaminated surfaces and materials. 

    Early detection, supportive treatment and rapid public health measures significantly improve survival and are critical to stopping transmission.

Source: 

Link: https://www.afro.who.int/countries/democratic-republic-of-congo/news/democratic-republic-congo-confirms-new-ebola-outbreak-who-scales-upsupport

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Characterization of atypical #Ebola virus disease in #ferrets

 

Abstract

Ebola virus (EBOV) infection typically results in severe—and often lethal—acute disease. However, increasing evidence suggests that EBOV can persist in certain immune-privileged tissues, which may then serve as reservoirs for the later reemergence of EBOV and disease recrudescence. Here, we report atypical EVD recrudescence in a ferret model inoculated with an otherwise lethal dose of EBOV and treated with low doses of a highly potent monoclonal antibody cocktail. Among 32 antibody-treated ferrets, 14 animals survived, while 8 succumbed to acute EVD within about 5–8 days. The remaining 10 animals succumbed to atypical EVD between 12 and 18 days post-infection (DPI) despite having shown no, or very minor, signs of illness during the acute phase of disease. While viremia disappeared by 14 DPI in most animals that succumbed to atypical EVD, it rebounded modestly just prior to death. Unlike animals that died of acute EVD, those that died of atypical EVD showed only a moderate systemic inflammatory response and few signs of organ dysfunction, in line with low levels of virus in the liver and spleen. Interestingly, however, ferrets that died of atypical EVD showed high levels of virus in the brain, consistent with increased markers of inflammation in the central nervous system and significant pathological changes, including a breakdown in the blood-brain barrier and severe meningoencephalitis. Not only does this study shed important light on the atypical and underappreciated manifestations of EVD, but it also establishes the ferret as a valuable model of EBOV recrudescence.

Source: 

Link: https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1013916

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The #Mengla virus (Filoviridae: #Dianlovirus)

 

Abstract

Introduction. 

Filoviruses associated with various species of pteropodid bats (Chiroptera: Pteropodidae) are traditionally regarded as potential causative agents of hemorrhagic fevers with epidemic potential. The known agents of Ebola and Marburg fevers periodically cause sporadic cases and epidemic outbreaks in African countries. Recent discoveries of novel filoviruses associated with pteropodid bats in South and Southeast Asia highlight the necessity to investigate their genetic diversity and pathogenic potential.

The aim of this study was to investigate the genetic diversity and pathogenic potential of new filoviruses associated with bats, based on literature data.

Materials and methods. 

This review is based on an analysis of published literature describing the detection and molecular characterization of novel filoviruses identified in different geographic regions, with a particular focus on filoviruses associated with pteropodid bats in South and Southeast Asia. The analyzed studies include data on virus discovery, genome organization, taxonomic classification, and experimental assessment of biological properties. 

Results. 

Several novel filoviruses have been identified by metagenomic RNA sequencing of tissues from pteropodid bats captured in South and Southeast Asia. Among them, Mengla virus was detected in tissues of pteropodid bats (Rousettus spp.) captured in Mengla County, Yunnan Province, People’s Republic of China. Owing to a high level of genetic divergence, Mengla virus was classified as a representative of a new genus, Dianlovirus, within the family Filoviridae. Although a live isolate of Mengla virus has not yet been obtained, experimental studies using chimeric minigenome systems and virus-like particles suggest that the virus may exhibit tropism for tissues of various vertebrate hosts, including humans.

Conclusion. 

Members of the family Filoviridae are widely distributed within the geographic range of their natural reservoir–pteropodid bats–across South and Southeast Asia, including viruses evolutionarily related to Ebola and Marburg viruses. Although human disease caused by Mengla virus and other recently discovered filoviruses has not been documented, the potential for cross-species transmission and the emergence of novel filovirus infections in endemic regions remains.

Source: 

Link: https://virusjour.crie.ru/jour/article/view/16805

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Confirming #ERVEBO #Vaccination to Support #Ebola Virus #Surveillance

 

Abstract

Accurate confirmation of Ebola vaccination (ERVEBO) is essential for interpreting serologic data and assessing vaccine coverage during Ebola virus (EBOV) outbreaks. Current GP1,2-based assays cannot reliably distinguish vaccine-induced immunity from responses generated by natural infection. We developed a multiplex Luminex assay incorporating EBOV GP1,2, secreted glycoprotein (sGP), and a modified vesicular stomatitis virus nucleoprotein (VSV-P-N), a vector antigen encoded by ERVEBO but absent from wild-type EBOV. By using samples from US vaccinees and controls and a small comparison set from the Democratic Republic of the Congo, we found sGP and VSV-P-N demonstrated 100% sensitivity and >97.6% specificity for identifying vaccinees. In samples collected after a ring vaccination campaign in Guinea, combined sGP and VSV-P-N positivity confirmed vaccination in 94.8% of persons with written and 90.8% of persons with verbal confirmation of vaccination history. Our findings show that sGP and VSV-P-N provide a reliable signature of ERVEBO vaccination and support improved Ebola surveillance.

Source: 

Link: https://wwwnc.cdc.gov/eid/article/32/4/25-1906_article

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#Glycoprotein-specific transcriptional response contributes to differential #vaccine #protection against lethal #Ebola virus #infection

 

Abstract

Since the West African Ebola virus (EBOV) epidemic in 2014-2016, recurrent outbreaks of the EBOV-Makona variant have been driven by recrudescence and human-to-human transmission emphasizing the need for effective vaccination strategies. A live-attenuated recombinant vesicular stomatitis virus (VSV)-based vaccine expressing the EBOV-Kikwit variant glycoprotein (VSV-Kik) received FDA approval in December 2019 and provides complete, rapid protection against EBOV-Makona as early as 7 days post-vaccination (DPV). During the 2018-2020 Ebola outbreak, the VSV-Kik vaccine, known as ERVEBO, was administered to lower-risk individuals at a 5-fold dose reduction of the standard 2 × 107 PFU to provide broader population protection. Identification of a protective lower dose providing rapid protection would ease supply burdens during future outbreaks and enhance vaccine coverage. We previously generated a VSV-based vaccine expressing the glycoprotein of the Makona variant (VSV-Mak) which provided complete protection against homologous challenge 28 DPV at as low as 1 × 101 PFU. However, the transcriptional responses engendered by VSV-Mak and VSV-Kik vaccines in the context of early EBOV-Makona challenge have not yet been evaluated. In the current study, we compared transcriptional responses following a low dose (1 × 104 PFU) of lab-grade VSV-Mak or GMP-grade VSV-Kik and subsequent EBOV-Makona challenge 10 DPV. VSV-Kik provided complete protection against heterologous challenge and elicited rapid antiviral transcriptional changes followed by the activation of adaptive immunity. On the other hand, VSV-Mak only provided partial protection and induced minimal transcriptional response. These results highlight a glycoprotein-specific transcriptional response after vaccination despite the high EBOV variant homology.

Source: Vaccine, https://www.sciencedirect.com/journal/vaccine/vol/79/suppl/C

Link: https://www.sciencedirect.com/science/article/abs/pii/S0264410X26002185?via%3Dihub

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Structures of #Marburgvirus #glycoprotein and its complex with NPC1 #receptor

 

Abstract

Marburgviruses (MBVs) cause severe haemorrhagic fever with higher fatality rates than Ebola virus (EBOV). Here we show that the MBV glycoprotein (GP) mediates viral entry more efficiently than EBOV GP. Using cryo-EM, we determined structures of MBV GP in three states: (1) unbound; (2) bound to its endosomal receptor NPC1; and (3) complexed with a neutralizing nanobody. The glycan cap shields the receptor-binding site from NPC1 but only partially from the nanobody, enabling limited immune evasion. After glycan cap cleavage, NPC1 binds to MBV GP in a distinct orientation compared with EBOV GP, providing an additional anchor and enhancing receptor affinity. NPC1 engagement also induces substantial conformational changes in MBV GP, probably facilitating membrane fusion. Furthermore, MBV GP is susceptible to the neutralizing nanobody, which mimics NPC1 at the receptor-binding site. Together, our findings reveal MBV GP as a highly efficient entry mediator and suggest structural mechanisms that may contribute to its enhanced entry efficiency.

Source: Nature, https://www.nature.com/

Link: https://www.nature.com/articles/s41586-026-10240-0

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#Marburg virus disease - #Ethiopia [End of the Outbreak] (#WHO, Jan. 26 '26)

 

{Excerpt}

26 January 2026

Situation at a glance

On 26 January 2026, the Ministry of Health of Ethiopia declared the end of the Marburg virus disease (MVD) outbreak. 

This declaration came after two consecutive incubation periods (a total of 42 days) since the last person confirmed with MVD died and was given a safe and dignified burial, in accordance with WHO recommendations on 14 December 2025. 

As of 25 January 2026, a cumulative total of 19 cases, including 14 confirmed (including nine deaths) and five probable cases (all deaths), were reported. 

A total of 857 contacts listed for monitoring all had completed their 21-day follow-up as of 25 January 2026. 

WHO, through its country office and partners, provided technical, operational and financial support to the government to contain this outbreak.

Description of the situation

On 14 November 2025, after the laboratory confirmation of suspected viral hemorrhagic fever (VHF) cases in Jinka town, South Ethiopia Regional State, Ethiopia, the Ministry of Health of Ethiopia declared an outbreak of Marburg Virus Disease (MVD). 

Molecular testing conducted by the National Reference Laboratory at the Ethiopian Public Health Institute (EPHI) identified Marburg virus (MARV) in patient samples. 

This was the first time Ethiopia was reporting a MVD outbreak.

The first known case was an adult from Jinka town who developed symptoms on 23 October. 

The patient presented to the General Hospital the following day with vomiting, loss of appetite, and abdominal cramps. 

As of 25 January 2026, a cumulative total of 14 confirmed cases, including nine deaths (Case Fatality Rate (CFR) 64.3%) and five probable cases, all of whom had died, were reported by the Ministry of Health from Jinka, Malle and Dasench woredas in South Ethiopia Region and Hawassa in Sidama Region.

As of 25 January 2026, a total of 857 contacts were listed who completed 21 days of follow-up, 760 from the South Ethiopia Region and 97 from the Sidama Region. 

As of 5 January 2026, 3800 samples were tested for the virus.

On 26 January 2026, after two consecutive incubation periods (a total of 42 days), without a new confirmed case reported, after the last confirmed case died and was given a safe and dignified burial, on 14 December 2025, the Ministry of Health of Ethiopia declared the end of the MVD outbreak, as per WHO recommendations.

(...)

Source: 

Link: https://www.who.int/emergencies/disease-outbreak-news/item/2026-DON592

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An #mRNA #vaccine encoding the #Ebola virus glycoprotein induces high neutralizing #antibody titers and provides strong protection against lethal infections in mouse models

 

Abstract

Ebola virus (EBOV) is the causative agent of Ebola disease (EBOD), a viral hemorrhagic fever with a notably high case fatality rate. Current treatments for EBOD are limited to monoclonal antibodies or two licensed viral vector vaccines, a recombinant vesicular stomatitis virus (rVSV)-vectored vaccine or an adenovirus and modified vaccinia Ankara regimen. However, comparisons of protection, efficacy, and durability with alternative nucleotide platforms remain understudied. Here, we evaluated the immunogenicity of an mRNA vaccine expressing the EBOV glycoprotein (GP) in parallel with rVSV- and DNA-based vaccine platforms. The mRNA EBOV-GP vaccine, formulated in lipid nanoparticles, elicited significantly higher levels of total IgG and neutralizing antibody titers compared to the rVSV-EBOV-GP vaccine. Linear antibody epitope analysis indicated a preference for targeting the mucin-like domain in EBOV-GP1 following rVSV-based vaccination, while the mRNA platform distinctly targeted the internal fusion loop of EBOV-GP2. After characterizing the immunogenicity of the mRNA vaccine, two models of EBOD were used to demonstrate its protective efficacy: a surrogate rVSV-based challenge model of EBOD using type-I interferon deficient C57BL/6 mice and infection of BALB/c mice with authentic mouse-adapted EBOV. In both studies, the EBOV mRNA vaccine fully protected the mouse cohorts against morbidity and mortality. Additionally, the EBOV mRNA vaccine produced greater neutralizing antibody titers compared to the DNA EBOV-GP vaccine. These results suggest that an mRNA vaccine expressing EBOV-GP can induce robust, functional humoral responses that are protective against EBOD, warranting further development as an alternative to, or as part of a vaccine strategy including, viral vectored vaccines.

Source: Frontiers in Immunology, https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2025.1682418/full

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#Genomic Insights into #Marburg Virus Strains from 2023 and 2025 #Outbreaks in Kagera, #Tanzania

 

Abstract

Marburg virus (MARV) is the primary cause of Marburg virus disease (MVD), a severe hemorrhagic fever with a high case-fatality rate. The first reported MVD outbreak in Tanzania occurred in 2023, followed by a second outbreak in 2025, both within the Kagera region. During those MVD outbreaks, 174 suspected cases were identified; of those, 10 were laboratory confirmed. After complete genome assembly and bioinformatic analyses, we found the MARV strains of the 2023 and 2025 outbreaks to be closely related and clustered with MARV strains that caused outbreaks in Rwanda (2024) and Uganda (2014). The sequences from both MVD outbreaks in Tanzania showed >99.71% nucleotide identity, suggesting a possible single spillover event followed by limited human-to-human virus transmission. Further ecologic studies are essential to identify potential spillover events, but our findings indicate that closely related MARV strains circulate in Kagera, Tanzania, posing a risk for future outbreak recurrence.

Source: 

Link: https://wwwnc.cdc.gov/eid/article/32/1/25-1314_article

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