Bundibugyo Ebola Strain Resists Existing Vaccine, Undermining Proven Response Strategy

The 2026 DRC outbreak stems from Bundibugyo virus, which evades rVSV-ZEBOV (Ervebo)—the vaccine that contained the 2018–2020 Kivu epidemic. No licensed vaccine targets Bundibugyo. Ring vaccination, the epidemiological cornerstone of recent Ebola control, is no longer viable. The virus spreads through direct bodily fluid contact. Responders must now depend on protective equipment, surveillance, and isolation in a conflict-ravaged region where those tools face severe constraints.