by Vaibhavi M.
7 minutes
Managing "Bleeding Eye Virus" Risks & Vaccine Pipelines
Marburg virus: 20–90% fatality rate, transmission routes, healthcare worker risks, IAVI vaccine pipeline (Phase 1 2026) and infection control.
AT A GLANCE
Pathogen | Family | Fatality Rate | Reservoir Host | Approved Vaccine? |
|---|---|---|---|---|
Marburg virus / Ravn virus | Filoviridae (same as Ebola) | 20% – 90% | Egyptian Rousette bat | None as of 2026 |
1. What Is the 'Bleeding Eye Virus'?
Marburg virus disease (MVD) is a rare but extremely dangerous viral hemorrhagic fever. It gets its alarming nickname 'bleeding eye virus' because, in severe cases, the body can start bleeding from the eyes, nose, mouth, and gut. It belongs to the Filoviridae family, the same virus family as Ebola, and can be just as deadly.
The virus was first identified in 1967 in Marburg, Germany, when laboratory workers became ill after handling monkeys imported from Uganda. Since then, sporadic outbreaks have been recorded across sub-Saharan Africa. Two types of orthomarburgviruses cause the disease: Marburg virus and Ravn virus.
The natural host for the virus is the Egyptian rousette bat (Rousettus aegyptiacus). People can get infected through direct contact with these bats or their body waste. Once the virus 'spills over' into humans, it can spread from person to person through contact with infected individuals' body fluids.
2. How Does It Spread & Who Is at Risk?
Transmission Routes
Marburg spreads through direct contact, not through the air like the flu. The key routes of transmission are:
- Contact with body fluids (blood, saliva, urine, semen) of a sick or deceased person
- Handling items contaminated with an infected person's fluids (bedding, needles, clothing)
- Contact with infected Egyptian rousette bats or their excretions in caves or mines
- Sexual transmission is possible: the virus can persist in the semen of recovered male patients
Who Is Most at Risk?
Risk Group | Reason for Elevated Risk |
|---|---|
Healthcare workers | Direct exposure to infected patients without adequate PPE, 80% of Rwanda 2024 cases were healthcare workers |
Cave/mine workers in Africa | Contact with Egyptian rousette bats that carry the virus |
Family caregivers | Close contact with ill patients at home, often without protective equipment |
Travelers to endemic regions | Visiting areas with active bat populations or during outbreak periods |
Laboratory workers | Handling primate samples or live virus in research settings |
3. Clinical Picture: What Happens in the Body?
MVD develops in stages. Understanding these stages is critical for early detection, isolation, and treatment decisions.
Stage | Timeframe | Key Symptoms |
|---|---|---|
Early (Dry phase) | Days 1–4 | Sudden fever, chills, severe headache, muscle pain, fatigue symptoms look like flu or malaria |
Middle (Wet phase) | Days 5–7 | Nausea, vomiting, diarrhoea, abdominal cramps and a non-itchy rash on the torso |
Severe/Haemorrhagic | Days 7–9 | Bleeding from eyes, nose, gums, and GI tract; liver failure; delirium; shock |
Outcome | Days 8–10 | Death (in 20–90% of cases) or slow recovery over weeks in survivors |
A key clinical challenge is that early symptoms closely mimic malaria, typhoid fever, and bacterial pneumonia. This makes early diagnosis extremely difficult, especially in resource-limited settings in Africa. Clinicians must rule out these more common diseases while simultaneously taking infection control precautions.
Survivors can face long-lasting complications, including inflammation of the testicles, liver, and eye (uveitis), as well as psychiatric symptoms. Importantly, the virus can persist in immune-privileged sites, including the eyes and semen, even after full recovery.
4. History of Outbreaks: A Rising Concern
MVD has been recorded in 14 countries across four decades, with outbreaks becoming more frequent in recent years.
Year | Country | Cases | Deaths | Case Fatality Rate |
|---|---|---|---|---|
1967 | Germany / Yugoslavia | 31 | 7 | ~23% |
2004–2005 | Angola | 252 | 227 | 90% |
2012 | Uganda | 15 | 4 | 27% |
2021 | Guinea | 1 | 1 | 100% |
2022 | Ghana | 3 | 2 | 67% |
2023 | Equatorial Guinea | 16 confirmed + 23 probable | 12 confirmed + 23 probable | 75%+ |
2023 | Tanzania | 9 | 6 | 67% |
2024 | Rwanda | 66 | 15 | 23% |
2025 | Tanzania | ~10 | 10 | ~100% |
2025–2026 | Ethiopia | 14 | 9 | 64% |
The 2024 Rwanda outbreak was particularly alarming for the pharmaceutical and healthcare sector: 80% of confirmed cases were healthcare workers in Kigali hospitals. This highlighted how hospital-acquired (nosocomial) transmission can rapidly amplify an outbreak when infection control protocols are not strictly followed.
Ethiopia's 2025–2026 outbreak, the country's first ever, was declared over on January 26, 2026, with 14 laboratory-confirmed cases and 9 deaths. Ethiopia is now in a 90-day enhanced surveillance period.
5. Current Risk Level: What Pharma & Healthcare Organisations Need to Know
Global Risk
The World Health Organisation (WHO) has listed the Marburg virus as a priority pathogen requiring urgent research and countermeasure development, citing its epidemic potential and potential as a bioweapon. Outbreaks are becoming more geographically diverse. In 2025 alone, Ethiopia became the sixth new country in four years to report its first outbreak.
Risk to Healthcare Workers
The secondary attack rate of Marburg is estimated at 21%. For healthcare organisations, key risks include:
- Inadequate PPE during patient care, full PPE, including gown, gloves, face shield, and respirator, is required
- Insufficient isolation facilities in hospitals treating suspected or confirmed cases
- Post-recovery sexual transmission risk in male survivors, viral persistence in semen
- Staff managing recovered patients may still face exposure without testing confirmation
Risk Outside Africa
So far, all major outbreaks have been in sub-Saharan Africa. However, imported cases have occurred in the USA (2008) and the Netherlands (2008) in returning travellers. The CDC currently assesses the risk to the United States as low but continues active monitoring.
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6. Vaccine Pipeline: Where Does the Science Stand?
As of 2026, there are no licensed vaccines or approved specific treatments for Marburg virus disease. This represents a significant gap in global health preparedness. However, multiple candidates are in the pipeline:
Vaccine Candidate | Developer | Technology | Stage | Key Notes |
|---|---|---|---|---|
rVSV∆G-MARV-GP | IAVI + Partners (BARDA-funded) | Recombinant vesicular stomatitis virus (rVSV), same platform as Merck's approved Ebola vaccine ERVEBO® | Phase 1 (IAVI C104 trial scheduled early 2026) | Single-dose; complete protection in non-human primates; both intramuscular and intranasal delivery tested |
cAd3-MARV | GlaxoSmithKline / NIH | Chimpanzee adenovirus vector | Preclinical / Early Phase 1 | Part of the broader filovirus vaccine programme |
VRC-MARVDNA023-00-VP | NIH Vaccine Research Centre | DNA vaccine | Preclinical | Research-stage; not yet in human trials |
MV-MARV (Measles vector) | Various academic groups | Measles virus vector | Preclinical | Investigational; early-stage research only |
IAVI's Candidate: Key Data Points
- Platform: Built on the same rVSV backbone as ERVEBO® (licensed Ebola vaccine), giving it regulatory precedent
- Animal data: A single intramuscular dose fully protected non-human primates against lethal MARV challenge
- Intranasal route: Animals vaccinated via the nasal route were also fully protected against aerosolised MARV, which is important for biodefence scenarios
- Funding: Supported by BARDA and the U.S. Department of Defence's Defence Threat Reduction Agency
- Human trials: Phase 1 clinical trial (IAVI C104) planned to begin in early 2026
The use of a proven platform (rVSV) is significant, as it reduces the regulatory and manufacturing uncertainty compared to completely novel technologies. If Phase 1 safety data are favourable, this candidate could move rapidly to Phase 2/3 trials, especially if an outbreak creates an emergency use context.
7. Current Treatment: Supportive Care Only
There are no approved antivirals or specific drugs for MVD. Current clinical management is entirely supportive, meaning the goal is to keep the patient alive and stable while the body fights the virus. Supportive care includes:
- Intravenous fluid replacement to prevent dehydration from vomiting and diarrhoea
- Maintaining oxygen levels and blood pressure
- Treating secondary bacterial infections with antibiotics
- Pain and fever management
- Electrolyte balancing
Research into specific treatments is ongoing. Experimental approaches include monoclonal antibodies, small-molecule antivirals (such as remdesivir analogues), and RNA interference, but none have reached the approval stage for MVD.
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8. Infection Control: What Healthcare Facilities Must Do
Strict infection prevention and control (IPC) is the primary defence until a vaccine is available.
IPC Area | Recommended Action |
|---|---|
Patient isolation | Immediate placement in a private room with a closed door; ideally, negative-pressure isolation for confirmed cases |
Personal Protective Equipment (PPE) | Full PPE: gloves, fluid-resistant gown, face shield or goggles, N95 or higher respirator |
PPE donning/doffing | Trained in the supervision of PPE removal, as incorrect removal is a leading cause of healthcare worker infection |
Waste management | All clinical waste from MVD cases is treated as Category A infectious material |
Contact tracing | All contacts monitored for 21 days (maximum incubation period) after last exposure |
Deceased patient care | Safe and dignified burial practices; the family members should not wash the body |
Survivor monitoring | Male survivors should use condoms and have semen tested until a virus-free status is confirmed. |
9. Key Takeaways for Pharma & Healthcare Stakeholders
- Marburg is a high-priority pathogen; outbreaks are increasing in frequency and geographic spread.
- No approved vaccine or treatment exists; this is both a public health gap and a significant market opportunity for developers.
- IAVI's rVSV-based candidate is the most advanced, entering Phase 1 human trials in 2026, with strong preclinical data
- Healthcare workers are disproportionately affected; robust IPC training and PPE supply chains are critical investments.
- The pharma industry should prepare medical countermeasure (MCM) plans for MVD, particularly organisations operating in or sourcing from sub-Saharan Africa.
- Regulatory agencies (FDA, EMA) have emergency use and accelerated approval pathways that could be triggered during a large outbreak; vaccine developers should engage early.
References
- African Journal of Biomedical Research. Marburg Virus Disease. https://africanjournalofbiomedicalresearch.com/index.php/AJBR/article/view/5575/4320
- Centres for Disease Control and Prevention. Marburg Virus Disease. https://www.cdc.gov/marburg/index.html
- CDC. Marburg Outbreak in Ethiopia: Current Situation (Updated January 2026). https://www.cdc.gov/marburg/situation-summary/index.html
- CDC. About Marburg Virus Disease. https://www.cdc.gov/marburg/about/index.html
- CDC. History of Marburg Outbreaks. https://www.cdc.gov/marburg/outbreaks/index.html
- CDC. Clinical Overview of Marburg Virus Disease. https://www.cdc.gov/marburg/hcp/clinical-overview/index.html
International AIDS Vaccine Initiative (IAVI). Marburg Virus Vaccine Program. https://www.iavi.org/our-work/emerging-infectious-diseases/marburg-virus-vaccine/
