DRC's Bundibugyo Ebola outbreak passes 6,750 cases as a 61st health zone reports

The Bundibugyo virus outbreak in the Democratic Republic of the Congo has grown again. In its latest Disease Outbreak News, published on 10 September, WHO reports that as of 7 September the DRC had recorded 6,757 confirmed cases and 3,267 deaths, a crude case fatality ratio of 48.3% [s1]. The outbreak has reached a 61st health zone — Kayna, in North Kivu — and now spans six of the country's 26 provinces: Bas-Uélé, Haut-Uélé, Ituri, North Kivu, South Kivu and Tshopo [s1]. This continues the trajectory we tracked when the outbreak reached 60 health zones in late August.

Counting the small number of cases outside the DRC, the cumulative total is 6,778 confirmed cases: 6,757 in the DRC — including two people diagnosed there and later treated in Germany — plus 20 in Uganda and one in France [s1]. A total of 3,269 deaths have been reported, including two in Uganda, and at least 1,611 people have recovered: 1,590 in the DRC, 18 in Uganda, two in Germany and one in France [s1]. The international spread recorded earlier in the outbreak has not resumed; the growth is domestic.

What changed since the last update

Since the previous Disease Outbreak News of 28 August, the DRC has reported an additional 963 confirmed cases and 481 confirmed deaths [s1]. WHO gives its now-familiar dual explanation: part of the rise reflects stronger surveillance, expanded laboratory testing, better diagnostic capacity and the reconciliation of previously unreported data, and part of it reflects genuine, continued community transmission and geographic spread [s1]. The two are hard to separate in real time, which is why WHO reports both rather than attributing the increase to either alone.

Of the 61 affected health zones, 51 across five provinces have reported at least one confirmed case in this reporting period, an indication that transmission is not confined to a handful of hotspots but distributed across a wide area [s1]. The variation in how fast cases are accruing from zone to zone is part of why WHO describes the transmission dynamics as heterogeneous and the response as difficult to stabilise [s1].

The case fatality ratio near 48% is the number that keeps defining this outbreak. WHO frames it as a marker of the disease's severity compounded by persistent operational problems — delays in detecting cases, gaps in early and adequate patient care, and difficulty interrupting transmission [s1]. Late detection, it notes, keeps raising the risk of onward spread within households, communities and health facilities [s1].

The cross-border picture

WHO says the sustained level of transmission continues to pose a risk of cross-border spread [s1]. Health screening and surveillance remain in place at airports, ports and official land border crossings, but travel through informal routes persists and could still carry the virus across borders [s1]. That is the rationale for the strengthened cross-border coordination and preparedness WHO continues to call for, even though confirmed cases outside the DRC remain few and no new international exportation has been reported in this update [s1].

The outbreak is caused by Bundibugyo virus, one of the species that cause Ebola disease [s1]. For the clinical and virological background, and for how vaccination has been used in this outbreak, see our earlier coverage of what Bundibugyo virus disease involves and health-worker vaccination with Ervebo. This update is, for now, an accounting of an outbreak that continues to expand faster than it is being contained.

Sources

• [s1] Ebola disease caused by Bundibugyo virus – Democratic Republic of the Congo, World Health Organization (Disease Outbreak News), 10 September 2026.