Published: 09/03/2026
A Stanford Medicine infectious disease expert discusses his new research that models Ebola vaccines which have varying degrees of efficacy.
By Jamie Hansen, Global Health Communications Manager
Ebola is racing through the eastern part of the Democratic Republic of the Congo (DRC), outpacing urgent efforts to halt it. Bundibugyo virus, the rare Ebola strain responsible for the outbreak, has no approved vaccine or treatment, and it’s fatal in about half of cases. This places a heavy burden on the DRC’s health care system, which is weakened by armed conflict, severe international funding cuts, mass displacement, and other disease outbreaks.
Given the outbreak’s urgency, researchers and health officials have begun evaluating how vaccines designed for other Ebola strains, assumed to provide partial protection, could influence outcomes. At the same time, safety testing is beginning for new, Bundibugyo-specific vaccine candidates.
As the World Health Organization begins sending doses of the existing Ervebo vaccine to the DRC, Stanford Medicine-led research in The Lancet Infectious Diseases sheds important light on the vaccine’s potential to contain the outbreak. Researchers led by infectious disease professor Jason Andrews, MD, modeled vaccines of varying effectiveness alongside other prevention strategies. Assuming 45% protection against Bundibugyo, the study found that a vaccine like Ervebo could contain transmission and save lives when deployed broadly and rapidly, but the approach is resource-intensive and time-sensitive.
The findings emphasize the importance of increased international support for contact tracing, containment and diagnostics alongside vaccine access, Andrews said.
“Having more resources poured into this response is critical because we are so far behind where we need to be,” he said.
Andrews, a global health faculty fellow at the Stanford Center for Innovation in Global Health, discussed his findings and their implications for the outbreak response as well as for future global health threats in a Q&A with Stanford Medicine.