BUNDIBUGYO VIRUS DISEASE REASSESSED VIROLOGY, EPIDEMIOLOGY AND CLINICAL MANAGEMENT OF THE 2026 CENTRAL AFRICAN OUTBREAK

Abstract

Bundibugyo virus (BDBV), an emerging orthoebolavirus, was first detected in Uganda in 2007 and has historically received less scientific and public attention than Ebola virus and Sudan virus. The current outbreak in Central Africa provides an opportunity to reassess its epidemiology, clinical impact, molecular characteristics, and preparedness needs. This review consolidates current knowledge of BDBV from previous outbreaks and recent advances in molecular virology, reservoir ecology, diagnosis, clinical management, therapeutics, vaccines, and outbreak response. Available evidence indicates that BDBV has caused recurrent outbreaks, with estimated case-fatality rates ranging from 25% to 54.8%, while the 2026 outbreak has had a substantial regional impact. Genomic studies demonstrate considerable differences between BDBV and other orthoebolaviruses, particularly in the glycoprotein, which may contribute to limited cross-protection from Ebola virus-specific countermeasures. Although bats remain leading candidate reservoirs, a definitive natural host has not been identified. Diagnostic capacity is constrained by limited BDBV-specific assays and logistical challenges in conflict-affected settings, while the absence of licensed BDBV-specific therapeutics or vaccines limits available countermeasures. Experimental pan-ebolavirus monoclonal antibodies and multivalent vaccine platforms offer potential for broader cross-protection. Overall, the 2026 outbreak highlights how reservoir uncertainty, diagnostic limitations, incomplete countermeasure coverage, and fragmented responses in conflict-affected settings can amplify regional public-health consequences. Strengthening One Health surveillance, deployable molecular diagnostics, broadly protective therapeutics and vaccines, and genomic surveillance should therefore be prioritized to improve preparedness for future BDBV emergence.