WHO Disease Outbreak News 607, published 13 June, counted 695 confirmed Bundibugyo Ebola cases and 138 deaths across the Democratic Republic of the Congo and Uganda, a rise of 30 percent in five days from the 534 confirmed at DON6061. Bundibugyo is one of six Ebola species, and this is the largest outbreak ever recorded for it. The World Health Organization, the United Nations health agency that tracks outbreaks worldwide, publishes the Disease Outbreak News series as its authoritative case log.
The confirmed case-fatality ratio, the share of laboratory-confirmed cases that end in death, sits at 20.1 percent in DRC, roughly one in five. The outbreak now spans 29 health zones across three provinces: Ituri, North Kivu and South Kivu. Contact tracing, the work of finding and watching everyone a patient has been near, has climbed to 71.4 percent in Ituri, 71 percent in North Kivu and 83.5 percent in South Kivu, up from the 20 percent baseline in the CDC reproduction-number model that named one variable as the outbreak's fork.
Tracing tells responders where the virus might travel next, but it does not stop a sick person infecting others. That depends on isolation in a treatment bed, and isolation has not kept pace. The 71 to 83 percent tracing gain is real and hard-won; the figure that decides whether the outbreak peaks or runs is the slower one underneath it.
