6 Things to Know About Marburg Virus Disease

On September 27, Rwanda's Ministry of Health reported the country’s first outbreak of Marburg virus disease (MVD), a contagious viral infection that affects multiple organ systems and can lead to death. Rwanda has confirmed 66 cases and 15 deaths as of November 8th, making this the third largest known outbreak of MVD. 

As of November 8, the Rwandan Ministry of Health declared the outbreak under control, and the last remaining patients receiving treatment recovered. The Rwandan government led a comprehensive and notably effective response, and outbreak activities are now focused on research and disease surveillance.  

The World Health Organization (WHO) and other partner organizations are supporting the Rwandan government in their response by deploying experts and providing critical supplies needed for the outbreak response. A coordinated initiative to run critical vaccine and therapeutic clinical trials has reached over 1,600 frontline health care providers and high-risk individuals, such as mine workers.  

Inshuti Mu Buzima (IMB), as Partner’s In Health is known in Rwanda, and the University of Global Health Equity (UGHE) are closely aligned with the Rwandan government and have also supported the coordinated response. IMB is providing support and technical expertise, specifically in mental health and psychosocial support and helping ensure routine health care services remain available. UGHE provided technical expertise to the effort to identify the first documented patient and confirm the transmission source. 

Due to Rwanda’s highly effective response, no new deaths have been reported in more than four weeks. 

Considered a neglected tropical disease, progress toward the elimination of MVD has historically been slow. Limited MVD‐specific funding, research, and drug and vaccine development heightened the importance of public awareness and community involvement in reducing viral transmission. 

Infectious disease specialist Dr. Marta Lado, PIH’s director of clinical programs and health policy in Sierra Leone, and IMB’s MVD response clinical lead Dr. Erick Baganizi, head of the division for clinical programs at IMB, agree that broader and more detailed clinical data is required to better understand the disease. 

As candidate vaccines and therapeutics emerge, Lado and Baganizi focus on prevention methods and improved patient care. Below are six things they think you should know about MVD: 

1. MVD is not a new disease.

Since its initial detection in 1967, simultaneously in Germany and Serbia, cases and outbreaks have been sporadic. Often found in remote regions, the disease has previously been reported in Angola, the Democratic Republic of Congo, Ghana, Guinea, Kenya, South Africa, and Uganda, with the most recent outbreaks occurring in Equatorial Guinea and Tanzania between February and June 2023.

2. MVD is a contagious viral infection.

MVD spreads through direct contact with the blood, organs, or bodily fluids of infected humans or animals, and with surfaces, objects, and materials contaminated with the virus. 

The disease is introduced to human populations through infected bats and primates, usually after prolonged exposure to mines or caves inhabited by wildlife. In fact, the first outbreaks in Frankfurt and Marburg, Germany, and in Belgrade, Serbia, were associated with laboratory work using green monkeys imported from Uganda. The current outbreak in Rwanda is linked to transmission from a fruit bat. 

Once MVD is transmitted from animals to humans, it can spread to other people through contact with contaminated bodily fluids from those who are infected. 

People infected with MVD can infect others as soon as they are symptomatic, and they remain infectious as long as the virus is present in their blood. 

3. Symptoms can develop quickly as the illness advances.

The time between exposure to MVD and the appearance of symptoms varies from two to 21 days. Once symptoms appear, the disease can progress rapidly. 

In the first stage of MVD, symptoms can seem malaria-like and occur abruptly with high fever, headaches, fatigue, feelings of weakness, and localized pain in joints and muscles. Gastrointestinal symptoms, such as diarrhea, abdominal pain, nausea, and vomiting can also occur in this stage of the disease; but amid the current and most recent outbreaks, they have not been commonly observed. 

As it advances, MVD can become more severe, leading to multi-organ dysfunction. In days, renal and liver failure can develop, as well as respiratory distress, seizures, loss of consciousness, anemia, hepatitis, hemorrhaging, blood vessel damage, and delirium. 

4. MVD can be fatal.

The average MVD case fatality rate is around 50%, ranging from 24% to 88% in past outbreaks. Through supportive care facilitated by a robust health care system, most of Rwanda’s infected patients survived, putting the case mortality rate for this outbreak at around 23%, among the lowest ever recorded for the disease. 

Some patients only experience fever symptoms that resolve on their own, without treatment. Others, however, arrive at care facilities already suffering from organ failure, difficulty breathing, and central nervous system disruptions, making their cases more difficult to manage and lowering their chances of recovery. 

Moreover, the time needed to accurately diagnose MVD can put patients and health care workers at a lethal disadvantage. Symptoms of the disease, similar to other infectious diseases commonly found in areas where MVD is detected, are often mistaken for typhoid fever, food poisoning, and malaria, as was the case in Rwanda for the earliest cases. 

In fatal cases, death is usually preceded by severe blood loss and shock, occurring most often between eight to nine days after symptoms start.

5. Survival depends on effective supportive care.

While other medical conditions can further complicate the disease, even people who are considered healthy can have poor outcomes. 

There are currently no fully approved vaccines or antiviral treatments for MVD. 

The most effective approach to managing the disease, proven to increase chances of survival, is the delivery of intensive supportive care, which includes rehydration, antibiotics to prevent complications and super infections from bacteria, blood transfusions, medical oxygen therapy, and other treatments for specific symptoms. 

Access to supportive care played a critical role in lowering the MVD case fatality rate in Rwanda.  

6. Health care workers are especially vulnerable to MVD.

Clinicians, laboratory workers, and other people caring for individuals sick with the disease face an increased risk of infection. Because of difficulties clinically distinguishing MVD from other diseases, health care workers not yet aware of the need for isolation protocols and proper protective equipment are vulnerable to prolonged and potentially deadly virus exposure. 

Despite a swift and effective response to the MVD outbreak, over 80% of Rwanda’s confirmed cases were among health care workers, emphasizing the need for enhanced protection for frontline workers, surveillance and contact tracing, and additional resources for infection prevention and control practices within health facilities.