As health officials work to contain a growing Ebola outbreak in Central Africa, questions are resurfacing about why some strains of the virus still lack approved treatments nearly 50 years after Ebola was first identified.
The World Health Organization (WHO) has reported 900 suspected infections and 220 deaths through ongoing transmission of the Ebola virus in parts of the Democratic Republic of Congo (DRC) and Uganda.
The agency warned that outbreaks in conflict-affected and resource-deprived regions can escalate quickly if containment efforts falter.
The virus was first discovered in 1976 near the Ebola River in Zaire, now the DRC. Licensed vaccines such as Merck’s Ervebo have since shown strong protection against the Zaire strain of Ebola, responsible for major outbreaks in West Africa from 2014-2016 and the DRC from 2018-2020.
However, no approved vaccine or specific antiviral treatment yet exists for the Bundibugyo strain, which is responsible for the latest outbreak.
Public health experts say the gap reflects long-standing research priorities that have centered on the most extensive and lethal Ebola variants, leaving less common strains with fewer medical remedies.
Dr. Amesh Adalja, a senior scholar at Johns Hopkins Center for Health Security in Baltimore, Maryland, said Ebola vaccine development initially focused on the Zaire strain due to both its outbreak history and biodefense interest.
“Vaccines targeted to the Zaire species of Ebola were developed first because this species was the most common form of Ebola and also was the subject of Soviet bioweapons development efforts,” Adalja said.
“In recent years there have been programs developed to target the second most common form of Ebola, Sudan, and there is interest in Bundibugyo countermeasures as well.”
James Lyons-Weiler, Ph.D., author of “Ebola: An Evolving Story,” said any countermeasures taken to combat Bundibugyo have lagged due to delayed diagnostics and overall lack of preparedness.
“Everyone pretends the pathogen surprised them,” Lyons-Weiler said. “Bundibugyo did not appear from nowhere. The time to act is before, not after.”
Hellbound and Down 