OUTBREAK: Marburg Virus

Background

Marburg virus disease (MVD) is a zoonotic infectious disease caused by the Marburg virus (MARV) or Ravn virus (RAVV), belonging to the Filoviridae viral family. It was first discovered in 1967 after two simultaneous outbreaks occurred among laboratory workers in Germany and Serbia (formerly Yugoslavia). The laboratory workers were handling African Green Monkeys imported from Uganda. Since then, several MVD outbreaks have occurred predominantly in sub-Saharan Africa. Rousettus aegyptiactus bats are considered the natural animal reservoir for these viruses, and human infections have occurred after prolonged exposure to mines and caves where these bats live. 

MVD is a severe disease with a case-fatality ratio of up to 88%. Clinical presentation is similar to Ebola virus disease. Infected individuals commonly develop fever, severe gastrointestinal symptoms, and haemorrhagic manifestations. MVD is transmitted via direct contact with an infected person’s (or animal’s) blood, bodily fluids, deceased body, or surfaces contaminated with these fluids, putting healthcare workers at increased risk. Among those who survive MVD, the virus is known to persist in the placenta, breast milk, and semen. There are no licensed vaccines or therapeutics against MVD however, several medical countermeasures are in development. 

MVD Outbreak in Ethiopia

On 12th November 2025, the Federal Ministry of Health of Ethiopia and the Ethiopian Public Health Institute (EPHI) issued a press release following a cluster of suspected viral haemorrhagic fever cases in Jinka Town, South Ethiopia Regional State. 

On 14th November 2025, the National Reference Laboraratory confirmed detection of Marburg Virus, and the Federal Ministry of Health of Ethiopia confirmed the first MVD outbreak in the country. 

On 21st November, . WHO reported a potential risk for community transmission following unsupervised burial of fatal confirmed and suspected cases early in the  outbreak, and noted that cases in healthcare workers may have been evidence of potential exposure within health facilities. 

The Ministry of Health of Ethiopia publishes daily updates on the outbreak. As of 16th December, a total of 1938 laboratory tests have been conducted, leading to confirmation of 14 cases – nine of these confirmed cases have been fatal, and five have recovered. No cases were being treated as of 16th December; the last case completed treatment on the 13th December. 

Genomic analysis by the Ethiopia Public Health Institute (EPHI) has shown that that the virus belongs to the same strain as viruses known to have caused previous outbreaks in East Africa. .

The MOH and EPHI have launched a costed 3-month response plan. The national response has included public awareness campaigns, community screening, contact tracing, infection prevention and control, and treatment. Two hospitals have been designated as treatment centres, and a further site in Arba Minch has been designated for a new isolation center, with 12 beds for suspected cases and two beds for confirmed cases. 

The Ministry of Health of Ethiopia has reported receiving 2,500 doses of the investigational vaccine cAd3-Marburg developed by The Sabin Institute for use in vulnerable populations such as front-line health workers, and 640 doses for a phase II trial, with distribution being due to start in early December.

WHO assesses the public health risk posed by the outbreak as high at the national level, moderate at the regional level and low at the global level. Ethiopia’s response capacity is affected by concurrent emergencies and multiple disease outbreaks, including cholera, measles and dengue. The World Health Organization (WHO) and partners are supporting the government in its response.

For more information about the ongoing Marburg outbreak, click here.

Key Public Health and Research Updates

November 2025:

• Ethiopia declares its first outbreak of MVD.

March 2025:

• Tanzania declared the end of the Marburg Virus Disease outbreak after 2 confirmed and 8 probable cases were reported since it began in January, with a case fatality ratio of 100%. During the outbreak, the WHO Filovirus Research Consortium (CORC) met and released 10 research priorities for the ongoing outbreak in Tanzania and beyond. This was the second MVD outbreak in the country, the first occurring in 2023.

December 2024: 

• The Rwandan government declared the end of the Marburg Virus Disease outbreak, which lasted aproximately 3 months from September to December. During the outbreak, WHO published the ‘Marburg virus disease: Strategic preparedness and response plan for Rwanda. October – December 2024’ outlining a response strategy to rapidly contain the outbreak, establish treatment centers, strengthen infection prevention and control, and engage with communities. WHO published an appeal classifying this outbreak as Grade 3, the highest level requiring major WHO support, and estimated that 7.7 million USD would be required between October and December 2024 to provide necessary support.

August 2024: 

• WHO published infection prevention and control research priorities in healthcare settings for Ebola and Marburg.

April 2023: 

• The WHO Technical Advisory Group published candidate vaccines prioritised for inclusion in a Phase 1/2/3 study against MVD. 

March 2023: 

• A WHO R&D meeting with the MARVAC consortium was held to discuss medical countermeasures in development and integrating research during an outbreak.

February 2023: 

• WHO published a Marburg virus therapeutics and vaccine landscape outlining candidates in development.

July 2022: 

• A protocol for an international, randomized clinical trial platform based on a ring vaccination trial design, was developed by the Marburg Vaccine Trial Core Protocol Working Group.

June 2022: 

• The WHO R&D blueprint team published a Strategic Research Agenda for Filovirus Research and Monitoring (WHO-AFIRM) which outlines a long-term global strategy for filovirus research and monitoring between 2021-2031. 

Outbreak-Specific Research Priorities

The WHO R&D team published a Roadmap outlining research priorities for Ebola/Marburg in 2019. A recent Strategic Research Agenda for Filovirus (2021-2031) was published in 2021. This outlines strategic goals and milestones for Filovirus research under three pillars: Anticipation (to prevent and control outbreaks), Reinforcement (to develop and evaluate vaccines), and Cure (to develop post-exposure therapies).

Relevant Links

• WHO Disease Outbreak News on Marburg Virus Disease in Ethiopia, 24 November 2025
• Africa CDC Statement on Confirmed Marburg Virus Disease in Jinka, Southern Region, Ethiopia
• Ethiopia confirms first outbreak of Marburg virus disease | WHO | Regional Office for Africa
• A WHO-Strategic Research Agenda for Filovirus. Research and Monitoring (WHO AFIRM). WHO-AFRIM Strategy Roadmap 2021-2031. 

Clinical Trials Landscape 

A review of the landscape of our funding data on clinical trials can be obtained by applying the filters: Disease =Marburg > Study type = Clinical > Research categories = Therapeutics research development and implementation AND/OR vaccines research development and implementation on the left-hand filter bar.   

Pandemic PACT Data

See below our data visualisations for Marburg research grant funding.