Ebola: overview

Overview Ebola is a severe zoonotic infection caused by viruses in the genus Orthoebolavirus, with large human outbreaks caused primarily by Ebola virus (Zaire ebolavirus), Sudan virus, and Bundibugyo virus.1,2 The World Health Organization reports an average case-fatality rate of about 50% across outbreaks, with historical ranges from 25% to 90% depending on viral species, access to supportive care, and outbreak context.2 Virology Ebolaviruses are enveloped, nonsegmented, negative-sense single-stranded RNA viruses in the family Filoviridae.2,3 Their glycoprotein mediates host-cell attachment and entry, and viral replication triggers marked immune dysregulation, endothelial injury, and systemic inflammation that contribute to shock and multiorgan dysfunction.1,3 Among the clinically important species, Zaire ebolavirus has caused the largest and deadliest outbreaks and is the only species for which licensed vaccines and targeted monoclonal antibody therapies are currently available.1,4 Sudan virus and Bundibugyo virus cause clinically similar disease, but licensed countermeasures for these non-Zaire species are still lacking, which remains a...