ABUJA, NIGERIA – A deadly Ebola outbreak driven by a little-understood virus strain in the Democratic Republic of the Congo has crossed a grim threshold, exceeding 5,000 confirmed cases to rank among the worst Ebola epidemics ever documented. What makes this outbreak particularly alarming for global health authorities is its origin: the Bundibugyo virus, a rare Ebola variant for which no licensed vaccine or targeted treatment currently exists. As of Sunday, Congo’s Ministry of Health has logged 5,021 total cases, with a death toll reaching 2,378, marking this not only the deadliest outbreak of Bundibugyo Ebola on record but also the deadliest Ebola outbreak in the country’s modern history. The World Health Organization (WHO) has issued a stark warning that if unbroken transmission continues, the outbreak could eventually overtake the devastating 2014–2016 West Africa epidemic that killed more than 11,000 people.