Marburg virus outbreak: Officials rush to test vaccines

The Marburg virus illness, or MVD, was confirmed as having made its first outbreak in Equatorial Guinea on Tuesday, February 14, prompting the World Health Organization (WHO) in Geneva, Switzerland, to call an emergency meeting.

Nine fatalities and 16 suspected cases have so far been confirmed. The deadly illness, related to Ebola, causes similar symptoms to hemorrhagic fever and has a fatality rate of up to 88 percent.

What is the Marburg virus?

The term "viral hemorrhagic fever" describes a disorder that impairs the body's ability to function on its own and damages numerous organ systems, including the cardiovascular system as a whole. These conditions might have various symptoms, but bleeding or hemorrhaging is frequently one of them.

So far, we know that the outbreak is located in the Kié-Ntem region, which borders Cameroon and Gabon, in the north of Equatorial Guinea. According to John Edmunds, an epidemiologist at the London School of Hygiene & Tropical Medicine, who was at the meeting, the number of cases so far is higher than most of the 16 Marburg outbreaks previously identified.

"I cannot emphasize enough the need for speed," he said at the WHO meeting.

"Outbreaks have tended to be small and finish relatively quickly after effective interventions have been put in place," he told Nature in a press release.

At the meeting, officials also discussed the logistics of testing Marburg virus vaccinations in Equatorial Guinea. Viral-vector vaccines, such as the COVID-19 vaccine created by AstraZeneca and the University of Oxford in the UK, are among the top candidates.

Is there a vaccine for the Marburg virus?

The viability of testing Marburg vaccinations in various stages of development was also considered during the meeting. Though, it was asserted that the likelihood of a successful trial is low because other preventative measures, such as quarantine, might put an end to the outbreak before even a single dosage of the vaccine could be given.

Other potential vaccinations include one that instructs cells to produce a Marburg virus protein using a modified chimpanzee adenovirus. The Sabin Vaccine Institute in Washington, DC, proposed this.

Better yet, another candidate made by Janssen in Beerse, Belgium, uses the human adenovirus on which the company's successful COVID-19 vaccine was based (Janssen is a subsidiary of Johnson and Johnson).

None of these are available in large quantities, developers said at the meeting.

It's unlikely that enough cases will arise before the present outbreak is brought under control for researchers to establish with certainty whether any vaccine is effective or not.

That said, officials at the meeting stated that evidence supporting the efficacy of any vaccine might be gathered across numerous outbreaks. The effectiveness of vaccines and the immunological response they induce in communities at risk of epidemics in the future could both be learned from a vaccine experiment in Equatorial Guinea.