Scientists work toward a vaccine for filoviruses, Ebola's deadly kin
Filoviruses are among the globe’s most lethal—indeed, so dangerous they can be handled only in high-security laboratories. Yet, more than five decades after the discovery of the Marburg virus and nearly 50 years after the first outbreak involving its infamous cousin—the Ebola virus—questions still abound about the family Filoviridae.
Members of this deadly family emerged through zoonotic transmission, most likely jumping across multiple species barriers—from fruit bats to simian species and forest antelopes, then eventually to humans. It’s theorized that humans may have contracted the viruses through hunting and butchering bushmeat.
Mindful that only two vaccines exist, and both were designed to prevent Ebola virus infection, a multidisciplinary team of scientists at a U.S. military research institute has analyzed whether one of those vaccines might also confer immunity to other filoviruses. The research arrives as virologists at the University of Texas Medical Branch in Galveston are testing the antiviral pill known as obeldesivir, which so far appears capable of curing Rhesus macaques infected with Ebola virus. The medication is the oral form of the intravenous drug Remdesivir, originally developed for COVID-19.
Military researchers, meanwhile, conducted an in-depth series of experiments to determine whether a recombinant Ebola vaccine containing components of multiple filoviruses could serve as an off-the-shelf choice to prevent infection by filoviruses other than Ebola.
Their findings, however, didn’t produce the outcome they had hoped for. But the discovery that unfolded has helped pave the way to a broader understanding of what’s needed for a multivalent vaccine that guards against multiple filoviruses. Details of the research are reported in the journal Science Translational Medicine.
“Ebola virus is a negative single-strand RNA virus from the family Filoviridae that causes a virulent hemorrhagic fever, termed Ebola virus disease,” writes Dr. Thembi Mdluli, lead author of the new research and a computational biologist at Walter Reed Army Institute of Research in Silver Spring, Maryland.
Just as Ebolavirus is a negative single-strand RNA virus, so too are other filoviruses, which also cause a devastating hemorrhagic fever. Filoviruses are known for their morbidity and high mortality. Mduli and colleagues pointed to Marburg outbreaks in Africa, where fatality rates have ranged between 83 and 88%.
