Clinical profile and genomic characterization of the 2026 Bundibugyo virus index case in Uganda

Bundibugyo virus disease remains a high-consequence threat in Eastern and Central Africa, where cross-border mobility, nonspecific early symptoms and delayed recognition can obscure transmission. In this case report, we describe Uganda's 2026 Bundibugyo virus disease index case: a male patient who traveled from the Democratic Republic of the Congo to Uganda and was admitted to a private hospital in Kampala on 11 May 2026 after more than 2 weeks of vomiting and diarrhea, with epigastric pain, weakness and hiccups. He deteriorated rapidly, developing acute kidney injury, pulmonary edema, hepatic dysfunction, hypoxemia, delirium, atrial flutter, possible disseminated intravascular coagulation and multiorgan failure, and died on 14 May. A posthumous EDTA whole-blood specimen tested at the Central Emergency Response and Surveillance Laboratory was positive for orthoebolavirus RNA and confirmed as Bundibugyo virus by quantitative PCR with reverse transcription. Sequencing achieved 99% genome coverage at ≥100× depth. The 2026 Bundibugyo virus genome formed a distinct lineage approximately equidistant from the 2007-2008 Butalya and 2012 Isiro variants, differing by 216-227 nucleotides (~1.2% sequence divergence). Here, we demonstrate the value of fatality surveillance, private-sector surveillance, diagnostic optimization through national specimen referral and rapid molecular-genomic diagnostics for early detection, transmission chain interruption and public health response coordination.