The Marburg virus, together with the four known Ebola viruses, makes up the virus family known as filoviruses. These viruses cause a rare type of serious illness known as hemorrhagic (bleeding) fever. Marburg hemorrhagic fever can occur in both humans and other primates.

The Marburg virus was discovered in 1967 when some laboratory workers in Marburg and Frankfurt, Germany became ill with hemorrhagic fever. Some other medical personnel and family members of those affected also contracted the illness along with researchers in Belgrade, Serbia (formerly Yugoslavia). The outbreak was traced to exposure to African green monkeys which had been sent to Germany for research purposes and for preparation of polio vaccine.

Relatively little is known about the rare Marburg virus, which has only caused sporadic cases of hemorrhagic fever in the decades since its discovery. People have contracted the disease in Africa, but the exact region of Africa to which the virus is native is uncertain. Judging from the outbreaks so far, this region is thought to include parts of Uganda, Kenya and possibly Zimbabwe.

It is known that the virus is carried by animals, but the actual animal host for Marburg virus (and for the Ebola viruses) has not been identified. It is also unknown how the animal host transmits the virus to humans, but humans with Marburg hemorrhagic fever may pass the disease to other people, probably through contact with bodily fluids and secretions.

The signs and symptoms of Marburg hemorrhagic fever strike suddenly 5 to 10 days after infection with the virus and usually include fever, chills, headache, and myalgia (muscle aches). Nausea, vomiting, and chest or abdominal pain may also occur. A maculopapular rash (with both of flat and raised lesions) appears about 5 days after symptoms have begun. The disease can worsen to include pancreatitis, jaundice, delirium, and ultimately shock and multi-organ failure.

Up to a quarter of cases of Marburg hemorrhagic fever are fatal. Since the condition is rare and its signs and symptoms are similar to those of many other severe infections, the diagnosis of Marburg hemorrhagic fever can be difficult. Special immunological and molecular biological tests can identify the virus in body fluids and confirm the diagnosis.

There is no specific treatment for Marburg hemorrhagic fever. People with it should be hospitalized and receive supportive care that includes maintenance of circulation and blood pressure and regulation of fluids and electrolyte levels in the blood. Transfusions of blood and blood clotting factors may also be required.