Understanding Marburg Virus Disease

Marburg Virus Disease (MVD) is a deadly and emerging disease that all nurses and other healthcare workers should know. You may have seen the recent news about the outbreaks in Equatorial Guinea and Tanzania. The Centers for Disease Control and Prevention (CDC) recently issued an official health advisory urging clinicians and public health authorities to be alert for the possibility of travel-associated cases of MVD in the United States. Nurses and other healthcare workers should be educated and informed about MVD so that they can protect themselves, each other, and their patients and assist in limiting the spread of this rare and highly fatal hemorrhagic fever illness. Education and early recognition can help limit the spread of all infectious diseases, and MVD is no different.

Marburg Virus Disease is caused by two closely related zoonotic viruses that belong to the Filoviridae family: Marburg virus and Ravn virus. They are closely related to ebolaviruses and produce a very similar pathophysiological response to Ebola Virus Disease. The natural reservoir for these viruses is the Egyptian fruit bat which can be found across sub-Saharan Africa and parts of India and Pakistan. Case-fatality rates are estimated to be in the range of 23-90% without early identification and supportive medical interventions. It is important to remember that many recorded cases of MVD have occurred in impoverished parts of the world where access to quality medical care may be greatly delayed or completely unavailable, and early diagnosis and appropriate medical care may improve patient outcomes.

Transmission and Risk Factors

When assessing or triaging patients who present with febrile illness, a thorough travel history and exposure history are critically important. MVD can be transmitted to humans from interactions with infected animals (usually bats or rodents, although rarely, other non-human primates). This often occurs after spending time in caves or mines where bats live.  Human-to-human transmission of MVD may occur as a result of several different situations:

• Direct contact with the body fluids of an infected person (blood, urine, saliva, breast milk, vomit, stool, or semen)
• Direct contact with a deceased person's body who was infected (often through funeral practices)
• Contact with surfaces contaminated by infected body fluids (this includes unsafe injection practices)
• Rarely, infection resulting from contact with the semen of persons who have recovered from MVD

Symptoms and Progression of Illness

Marburg Virus has an incubation period of 2-21 days after exposure, meaning that a person may become sick at any point during that time. People with MVD are not contagious until symptoms appear, and not every person who contracts MVD will experience all symptoms associated with the illness.

Illness onset typically looks like a sudden high fever with severe headache and body aches, with GI symptoms such as abdominal pain, nausea, vomiting, and severe watery diarrhea appearing by day 3. Critically ill cases often suffer unexplained bruising and/or bleeding from multiple body sites by day 7. Neurological symptoms such as confusion and aggression may be evidenced during the late stages of illness. Complications related to blood loss, dehydration, and shock may lead to death by days 8-10 in severe cases of MVD, especially if intensive supportive care is not available.

Infection Control and Personal Protective Equipment (PPE)

If travel or exposure history findings are concerning and the patient presents with clinically compatible symptoms, immediately isolate the patient to prevent the potential further spread of MVD. According to the CDC, current isolation guidance for persons under evaluation for hemorrhagic fever illnesses such as Ebola or MVD is as follows:

• Single room with a private bathroom or a covered bedside commode
• Allow only essential healthcare workers who are competent in their roles to enter the room
• Keep a log of everyone who enters and leaves the room
• Avoid aerosol-generating procedures if possible

The use of pathogen-appropriate and well-fitting PPE should be a top priority for any healthcare team involved in the care of a patient who is suspected of having or diagnosed with MVD or any other hemorrhagic fever. Refer to your facility's infection control policy for their policy and procedure on this topic. Current and evidence-based infection control guidance may also be found on the websites of the World Health Organization and the Centers for Disease Control and Prevention.

Diagnosis and Treatment

Clinical diagnosis of Marburg Virus Disease can be difficult even for practitioners who are familiar with it because many of the symptoms are shared with other infectious diseases. Still, laboratory testing can confirm a suspected diagnosis. Currently, there are no FDA-approved therapeutics for MVD, but several immune therapies, vaccines, and drugs are under investigation. Early identification and aggressive supportive care, including fluid balance monitoring, oxygen supplementation, blood transfusions, and medications to address symptoms, may improve prognoses and reduce case-fatality rates. 

In summary, Marburg Virus is a rare pathogen in the West, but the presence of outbreaks in other parts of the world increases the chances that US-based healthcare workers could encounter travel-related cases. The increasing global connectedness of our modern society has made it possible for people and pathogens to travel long distances in a short time and raises the chances that we may encounter exotic and unfamiliar infections from time to time. Climate change and the continued encroachment of human civilization into animal habitats also create the potential for future novel pathogens to emerge from animal reservoirs. Education and preparedness about these rare and emerging diseases will help nurses and other healthcare workers optimize patient outcomes, slow the spread of infectious diseases, and improve health and safety across our populations.

References/Resources

Marburg (Marburg Virus Disease): Centers for Disease Control and Prevention

Perilous Pathogens: How Climate Change Is Increasing the Threat of Diseases: Council on Foreign Relations

Marburg virus disease: World Health Organization

Image Caption: Micrograph of Marburg virus. Image credit: University of Texas Medical Branch at Galveston.