WHO (the World Health Organization) declared the Bundibugyo outbreak in DR Congo the largest Ebola outbreak ever reported in the country on 14 August, in Disease Outbreak News bulletin 615 1. The count stood at 4,665 confirmed cases and 2,184 deaths as of 12 August, against 3,317 cases in the 2018-2020 epidemic in the country's east.
The milestone rests on a published case comparison, not on an elapsed-time counter, and that is worth pausing over. The 2018-2020 figure was produced by a laboratory network far smaller than the one running today, so part of the gap between 3,317 and 4,665 measures how many patients now get a test rather than how many people fall ill. WHO attributed most of the 1,060 cases added since its 1 August bulletin to the outbreak expanding, and part of it to stronger surveillance and diagnostic capacity. The 4,665 carries both mechanisms at once, and bulletin 615 separates neither.
The pathogen supplies the other half of the comparison. The 2018-2020 epidemic was Zaire ebolavirus, the species every licensed vaccine and monoclonal antibody was built against. This is Bundibugyo ebolavirus, one of six species in the genus, with three recorded outbreaks before this one. A record set by a species with no matched countermeasure is not the same event as a record set by one with two.
Geography now carries the risk. Transmission reaches 54 health zones across six provinces, the sixth arriving when Bas-Uele reported a case in Buta with symptom onset on 4 August. Ituri still holds 85% of cases and 79% of deaths, and the shape of the next bulletin depends on which of those two facts grows: an Ituri-dominated increment means a contained if brutal epicentre, while cases accumulating in the newer provinces means the response is chasing five fronts.
Carry the qualifier every time. Tedros Adhanom Ghebreyesus has twice called this the third-largest Ebola outbreak on record, and both statements hold: largest in this country's history, third globally. And 4,665 marks a floor rather than a total. WHO moved this outbreak to a confirmed-only basis in June, cutting around a thousand suspected cases from the headline at a stroke , and Jean Kaseya of Africa CDC put true infections at two to four times the tally a month later .
