What is the Marburg virus?
The Marburg virus, like the related Ebola virus, belongs to the group of filoviruses (Filoviridae). It is a virus with RNA genetic material and is named after the city in Hesse because people first became ill with the virus there in 1967. The laboratory employees were infected with the previously unknown virus in test monkeys that were imported from Uganda.
How dangerous is the virus?
People who become infected with the Marburg virus develop what is known as Marburg Virus Disease (MVD). The disease resembles the appearance of an Ebola infection. Those affected show symptoms of hemorrhagic fever, which begins with flu-like symptoms: high fever, chills, headache and muscle pain as well as gastrointestinal complaints and nausea. The symptoms increase as the disease progresses. After about a week, a rash and bleeding in the skin, mucous membranes and gastrointestinal tract appear. Neurological symptoms including coma can also occur.
If sufferers do not receive sufficient fluid and blood replacement, many of them ultimately die from internal bleeding and organ failure. According to the World Health Organization (WHO), the death rate is between 24 and 88 percent. There is no vaccination or specific therapy. However, an experimental vaccine is currently being tested in a clinical trial in Rwanda, Uganda and Kenya.
How is the Marburg virus transmitted?
The Marburg virus is not a human-pathogenic virus, but rather a so-called zoonotic pathogen. It primarily infects bats and flying foxes in Central Africa and multiplies in the animals, although they do not become ill themselves. People probably become infected through direct contact with bats or through other animals such as monkeys or antelopes as intermediate hosts that have been infected by bats. The viruses are found in the saliva and feces of these animals as well as in their meat. Any contact with these substances can lead to infection.
Subsequent transmission from person to person is also possible. This happens either through direct skin contact with body fluids such as blood, saliva and urine from sick people. Or people become infected through contaminated objects such as bed linen or medical devices. Unlike the coronavirus or flu viruses, the Marburg virus cannot be transmitted via droplet infections or the air.
What do we know about the current outbreak?
The suspicion that a man in Hamburg may have been infected with the Marburg virus recently made headlines. The affected person was a medical student who had contact with infected people in Rwanda before flying back to Germany. However, initial tests refuted the suspicion. However, due to the long incubation period of up to 21 days, the hamburger will continue to be monitored. It is considered unlikely that he could have infected other people on his journey from Africa.
The virus is currently spreading among people in Rwanda. So far, 46 people have been infected, twelve of whom died. The majority of those affected are employees in large hospitals. The outbreak was discovered and announced on September 27, 2024. How exactly the zoonotic species jump to the first patient occurred in this case is still unknown. Marburg virus outbreaks occur in Africa every few years, but usually only affect a few people. In the largest outbreak to date in Angola in 2005, 374 people were infected. The WHO assesses the global risk associated with the current outbreak in Rwanda as low.