While Equatorial Guinea is facing an epidemic of Marburg fever, researchers and representatives of NGOs and the pharmaceutical industry are mobilizing to urgently test vaccines or experimental drugs there, at the instigation of the Organization World Health Organization (WHO).
The alert was given on February 7 following deaths that occurred in the east of the country, in the forest province of Kie Ntem, bordering Cameroon and Gabon. To date, 9 deaths and around 20 suspected cases have been recorded. More than 4,000 people have been placed in quarantine in an attempt to block the spread of the virus.
“This is the first time that an outbreak has been confirmed in Equatorial Guinea: it is therefore a real emergence, in a country a priori without a history of hemorrhagic fever viruses. The last cases of Marburg were recorded in 2021 in Guinea Conakry and Ghana, two distant countries”, underlines epidemiologist Eric D’Ortenzio, specialist in emerging infectious diseases at the French National Institute of Health and Medical Research. (Inserm), in a article published on the site The Conversation.
No treatment available
Transmitted to humans through fruit bats, Marburg fever is a viral disease related to Ebola, the main symptoms of which are fever, bleeding, diarrhea and vomiting. Its lethality rate varies from 24% to 80% depending on the epidemics, according to the WHO.
Human-to-human transmission occurs mainly through contact with contaminated mucous membranes or blood. Marburg fever regularly causes epidemics, the most important of which occurred between 1998 and 2000 in the Democratic Republic of Congo (128 deaths) and between 2004 and 2005 in Angola (277 deaths).
There is currently no specific treatment for this pathology, but various laboratories around the world are working on the subject. Five candidate vaccines are presented, two of which have already been the subject of encouraging preliminary clinical trials: those of the firms Sabin and Janssen. Various drugs, including monoclonal antibodies, are also being studied.
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On February 14, the WHO invited various disease specialists to an emergency meeting to try to set up a clinical trial in Equatorial Guinea. Because designing such a trial requires respecting a certain number of steps: you have to select the most relevant vaccine or treatment, determine which people will receive it, seek the opinion of an ethics committee, import the required doses , etc. All in agreement with the government and local populations.
All of this takes time, and no one can say when the current epidemic will end. “WHO and experts wanted to avoid replicating what happened in Uganda during the Ebola outbreak that affected that country between September 2022 and January 2023. It had not been possible to assess the effectiveness of the vaccine candidate selected on this occasion, because by the time the clinical trial was set up, the epidemic was over”, relates Eric d’Ortenzio.
