Vaccine preparedness for Bundibugyo virus and lessons learned.

The ongoing 2026 outbreak of Bundibugyo virus (BDBV) in the Democratic Republic of the Congo and Uganda is the largest so far on record. Despite experience from previous Ebolavirus outbreaks, the current lack of vaccines against BDBV underscores a recurring failure in proactive preparedness. Here, we explore the most promising BDBV vaccine candidates and discuss the key lessons learned to guide more proactive, timely, and sustainable vaccine strategies for the future.