SWITZERLAND —The World Health Organization (WHO) has called an emergency meeting of the Marburg virus vaccine consortium (MARVAC), following a first-ever outbreak of deadly Marburg virus disease in Equatorial Guinea.
Marburg virus disease (MVD), a highly infectious disease similar to Ebola. The index case was reported on 7 January 2023, and there have been nine confirmed deaths associated with the outbreak, with 16 suspected cases in quarantine and 15 asymptomatic contacts being closely monitored from their homes.
The disease has a fatality ratio ranging from 24% to 88%. The virus is transmitted to humans through fruit bats and spreads between humans through direct contact with bodily fluids of infected people and materials.
The outbreak was not notified to the World Health Organization (WHO) until 7 February, but the organization has praised the rapid and decisive action by the Equatorial Guinean authorities in confirming the disease.
WHO experts said that they would soon convene a working group to prioritize existing vaccine candidates, with an eye to seeing if clinical trials for any of the vaccines can be launched in real time, particularly if the outbreak expands.
Philip R. Krause, chair of the WHO Covid Vaccines Research Expert Group, who led the meeting, said that the critical next steps included getting full sequence information on the virus, which is being detected in Equatorial Guinea, and the rapid convening of a vaccine prioritization committee to consider updated information from vaccine developers.
Krause added that assuming a study was to be done, it would be important to convene the prioritization committee to look at the most up-to-date information and make decisions about which of the vaccine candidates should be included in such a study.
At the meeting, the WHO experts reviewed the progress of five active vaccine candidates against the virus.
Janssen and Sabin Vaccine Institute are in Phase 1 clinical trials, while the other three candidates are still in the pre-clinical stage.
Janssen offered 3,500 doses of its candidate vaccine for WHO-led trials in Equatorial Guinea, but they must begin within the next two months.
The Sabin Vaccine Institute has up to 20,000 doses of the active vaccine ingredient and reserved “slots” with other manufacturers that could produce additional vials.
Public Health Vaccines has around 350 vials ready for use, but IAVI and Auro Vaccines do not have any available bulk drug substance or clinical trial material.
In terms of therapeutics, a recent study found that a combination of monoclonal antibodies and remdesivir performed better than individual drug agents.
WHO is deploying health emergency experts in epidemiology, case management, infection prevention, laboratory, and risk communication to support the national response efforts and secure community collaboration in outbreak control.