Development and characterization of a recombinant Bundibugyo virus expressing a fluorescent reporter protein

Bundibugyo virus disease (BVD), caused by Bundibugyo virus (BDBV), is associated with substantial morbidity and mortality, with previous outbreaks reporting case fatality rates of 30%-50%. The ongoing BDBV outbreak in the Democratic Republic of the Congo and Uganda highlights the urgent need for virus-specific research tools and medical countermeasures. Unlike Ebola virus disease caused by Zaire ebolavirus, no licensed vaccines or specific therapeutics are currently available for BVD. The lack of research tools has limited studies with BDBV. To facilitate antiviral testing and neutralization studies, we developed the first recombinant BDBV expressing the fluorescent reporter protein ZsGreen (rBDBV-ZsG). As a proof of concept, we tested a set of previously characterized antiviral compounds and demonstrated comparable inhibitory profiles between rBDBV-ZsG and the wild-type BDBV parental strain. Furthermore, the utility of rBDBV-ZsG was successfully evaluated in neutralization assays, demonstrating robust sensitivity and specificity using monoclonal antibodies and convalescent serum samples.