In this video from MedCram, Dr. Seheult talks about the Marburg virus outbreak that is currently happening in Rwanda.
What is Marburg virus?
Marburg virus comes from the family Filovirus and it is a non-segmented negative sense single stranded RNA. This family has EBOLA and Marburg Virus. From the Marburg virus there are two variants called Lake Victoria and Ravn. The word filovirus means long and stringy and on the surface of these viruses are glycoproteins. It was first discovered in 1967 in Uganda in monkeys. These monkeys were being trapped and being sent either to Marburg or Frankfurt Germany where scientists were working on polio vaccines and the monkeys were needed for cellular cultures. However, due to an ongoing war at that time, the monkeys could not be flown directly to those cities and instead had to be flown to London, England. In London, the airport workers were on strike and as a result these monkeys had to stay for 2 days in an animal locker. They were then transported to Marburg and Frankfurt in Germany as well as a third city Belgrade which at that time was Yugoslavia. The monkeys in Marburg and Frankfurt were killed shortly after arriving but those that had gone to Belgrade were kept alive for an additional six weeks. They were found to have an excess mortality of 33% so the scientists knew something was wrong with these monkeys.
Symptoms of Marburg virus
At all three of these sites, the personnel came down with fevers, body aches, and muscle aches. This was not known at the time, but the virus has a 5-9 day incubation period and infection. The first 3-4 days are a high fever up to 39 C, malaise, myalgias and headaches. By day 7 or end of the first week, one can see nausea, vomiting, and diarrhea. This is usually when hospitalization starts to occur. Of those people hospitalized, they noticed many of them started to have conjunctivitis and rashes. By the second week, the fever was usually lower around 38 C. However, this was the time when hemorrhages started to occur and elevation in liver functions tests, decreasing wbc and platelets were seen. People started to have bleeding everywhere. Those that died were somewhere between 7-16 days (average 9 days) and usually were the ones that had developed hemorrhage. Of those that survived, many went on to develop orchitis (in the reproductive organs) and it was found later that even as the person recovered, the virus was still present in these reproductive organs for a long time, and it could still be passed on to other people. There was a case report of a man passing it to his wife with sexual activity as there was viral particles in his semen 120 days past his acute infection. The case fatality rate thus far for males was 22.5% and for females was 25%. The mode of transmission was done via close contact or body fluids and it was not airborne. Finally they were able to identify the virus in 1967. Since then there have been a number of outbreaks and scientists have since learned the reservoir for this virus is bats.
Possible treatment trials for Marburg virus
Currently there is an outbreak in Rwanda as of October 2024. There have been about 56 cases and a dozen deaths. The CDC is screening travelers from Rwanda for the Marburg virus. Currently the therapeutics that have been developed for Ebola do not work for Marburg despite them being in the same family. There have been some other treatments that are being developed for Marburg virus. One of these is a traditional vaccine that Rwanda is planning to start vaccine trials on in the next few weeks. This article discusses that vaccine. In animals, it provided 100% protection. Then in January of 2024 there was phase 1 trial of the vaccine in humans and they found the vaccine to be safe, well tolerated and immunogenic and had no serious adverse events. Now in Rwanda, they are starting the phase 2 trial with 700 vaccine doses and targeting primarily the front line workers and other high risk adults. Currently there are no licensed vaccines or treatments for Marburg which can have a mortality of up to 88%. As these trials go on, MedCram will continue to cover and provide you with the latest updates.
LINKS / REFERENCES:
Forty Years of Marburg Virus (Journal of Infectious Diseases) | https://academic.oup.com/jid/article/…
Single-Shot ChAd3-MARV Vaccine in Modified Formulation Buffer Shows 100% Protection of NHPs (Vaccines) | https://www.ncbi.nlm.nih.gov/pmc/arti…
Safety, tolerability, and immunogenicity of the chimpanzee adenovirus type 3-vectored Marburg virus (cAd3-Marburg) vaccine in healthy adults in the USA: a first-in-human, phase 1, open-label, dose-escalation trial (Lancet) | https://www.ncbi.nlm.nih.gov/pmc/arti…
Rwanda to start vaccine trials for Marburg disease in a few weeks (Reuters) | https://www.reuters.com/business/heal…
Sabin Vaccine Institute Delivers Marburg Vaccines to Combat Outbreak in Rwanda (Sabin) | https://www.sabin.org/resources/sabin…
Sabin Vaccine Institute Delivers Marburg Vaccines to Combat Outbreak in Rwanda (GlobeNewswire) | https://www.globenewswire.com/news-re…
Marburg virus (Wikipedia) | https://en.wikipedia.org/wiki/Marburg…
CDC to screen travelers for Marburg, as outbreak of Ebola-like disease grows (CBS News) | https://www.cbsnews.com/news/traveler…
Emergence of Marburg virus: a global perspective on fatal outbreaks and clinical challenges (Frontiers) | https://www.frontiersin.org/journals/…