Since the last Disease Outbreak News was published on 28 August 2026, the Bundibugyo virus outbreak in the Democratic Republic of the Congo has expanded to one additional health zone, Kayna, in North Kivu. This increase brings the total number of affected health zones to 61 across six out of 26 provinces of the country: Bas-Uélé, Haut-Uélé, Ituri, North Kivu, South Kivu, and Tshopo. As of 7 September 2026, the Democratic Republic of the Congo has reported 6757 confirmed cases, including 3267 deaths, resulting in a crude case fatality ratio (CFR) of 48.3%. The transmission dynamics remain variable across affected locations, with evidence of ongoing geographical expansion and sustained increase in cases in some health zones. The continuously high CFR highlights the seriousness of the disease and persistent challenges in timely case detection, access to early and adequate patient care, and effective interruption of transmission. Delayed detection of cases continues to increase the risk of further spread within households, communities, and healthcare settings.
Since the publication of the previous Disease Outbreak News on 28 August 2026, additional confirmed cases and deaths of Bundibugyo virus disease (BVD) have been reported only in the Democratic Republic of the Congo.
As of 7 September 2026, a cumulative total of 6778 confirmed cases has been reported: 6757 in the Democratic Republic of the Congo (including two cases diagnosed in the Democratic Republic of the Congo and subsequently treated in Germany), 20 cases in Uganda and one case in France. Overall, 3269 deaths have been reported, including two in Uganda. As of 7 September, at least 1611 patients have recovered, including 1590 in the Democratic Republic of the Congo, 18 in Uganda, two in Germany and one in France.
The sustained level of transmission in the Democratic Republic of the Congo continues to pose a risk of cross-border spread. Health screening and surveillance activities remain operational at airports, ports, and official land border crossings; however, travel through informal crossing routes persists and may facilitate virus exportation, importation, and subsequent transmission. In this context, strengthened cross-border coordination, together with ongoing surveillance and preparedness efforts, remains critical to limiting further regional spread and supporting an effective public health response.
Figure 1. Distribution of cumulative confirmed cases of Bundibugyo virus disease in the Democratic Republic of the Congo, as of 7 September
Democratic Republic of the Congo
Since the previous Disease Outbreak News was published on 28 August 2026, an additional 963 confirmed cases, including 481 confirmed deaths, have been reported in the Democratic Republic of the Congo. While part of this increase may be attributable to strengthened surveillance activities, enhanced laboratory testing, improved diagnostic capacity, and reconciliation of previously unreported data, the continued growth in both cases and deaths also reflects sustained community transmission and significant geographic expansion of the outbreak. As of 7 September, the Democratic Republic of the Congo has reported a total of 6757 confirmed cases, including 3267 deaths (CFR 48.3%). A total of 1590 patients have recovered to date.
Confirmed cases have been reported from 61 health zones (HZ) across six provinces, with 51 HZ from five provinces reporting at least one case in the last 21 days. Ituri remains the most affected province, with 28 of its 36 health zones reporting cases, followed by North Kivu (16/34), Tshopo (7/23), Haut-Uélé (6/13), Bas-Uélé (3/11), and South Kivu (1/34). No new cases have been reported from South Kivu province since 29 May 2026. Kayna HZ in North Kivu province is the most recently affected area. As of 7 September, 71 new confirmed cases had been reported in the preceding 24 hours from 17 health zones located in Ituri, North Kivu, and Haut-Uélé provinces.
Ituri continues to be the epicentre of the outbreak, accounting for 5406 confirmed cases since the start of the outbreak, including 1114 new confirmed cases reported in the previous 21 days, as of 7 September. North Kivu is the second most affected province, with a cumulative number of 1066 confirmed cases, including 453 reported in the last 21 days, as of 7 September. One of the highest CFR (65.4%) observed in this outbreak has been reported from North Kivu province; and investigations are ongoing to better understand the factors contributing to this elevated mortality rate.
The number of individuals requiring follow-up as contact has also risen considerably with the expansion of the outbreak. As of 7 September, 85.3% of identified contacts were successfully monitored during the previous 24 hours with 21 359 contacts seen out of 24 719 requiring follow up. The large volume of contacts under surveillance highlights the extent of potential exposure within affected communities and the substantial demands placed on response operations.
The outbreak continues to unfold within a complex humanitarian setting characterized by insecurity, armed conflict, and widespread population displacement. More than 26 million people are experiencing acute food insecurity, while approximately one million internally displaced persons reside in Ituri Province alone. Ongoing insecurity and displacement limit access to healthcare and essential services, constrain the ability of response teams to reach affected areas, and impede surveillance, case investigation and contact tracing activities. Overcrowding, limited water, sanitation and hygiene services, and restricted access to healthcare in mining communities, informal settlements and sites for internally displaced persons further undermine early case detection, infection prevention and control measures, and the provision of timely care. These conditions also reduce the effectiveness of response interventions and outreach efforts.
Figure 2: Number of confirmed Bundibugyo virus disease cases in the Democratic Republic of the Congo, by date of notification, as of 7 September 2026
Figure 3: Number of deaths among confirmed Bundibugyo virus disease cases in the Democratic Republic of the Congo by date of notification, as of 7 September 2026.
Bundibugyo virus disease (BVD) is a severe Ebola disease caused by the Bundibugyo virus, one of the Orthoebolavirus species. It is a zoonotic disease, with fruit bats suspected to be the natural reservoir.
Human infection is thought to occur through close contact with the blood or secretions of infected wildlife, such as bats or non-human primates, and it subsequently spreads from person-to-person through direct contact with the blood, secretions, organs, or other bodily fluids of infected individuals or contaminated surfaces and materials. Transmission is particularly amplified in health-care settings when IPC measures are inadequate and during unsafe burial practices involving direct contact with deceased individuals.
The incubation period for BVD ranges from two to 21 days, and infected individuals are not infectious until symptom onset. Early symptoms such as fever, fatigue, muscle pain, headache, and sore throat are non-specific, which complicates clinical diagnosis and can delay detection. These symptoms then progress to gastrointestinal symptoms, organ dysfunction, and, in some cases, haemorrhagic manifestations.
The historical CFR from the past two BVD outbreaks, reported in Uganda and in the Democratic Republic of the Congo in 2007 and 2012, were 30% and 50%, respectively.
Differentiating BVD from other endemic febrile illnesses such as malaria is challenging without laboratory confirmation using polymerase chain reaction (PCR) or antigen- or antibody-based assays. Outbreak control relies on rapid case identification, isolation and care, contact tracing, safe burials and strong community engagement, as no approved vaccines or specific treatments currently exist for BVD.
Since first detected in May 2026, this BVD outbreak has rapidly evolved into a large and geographically expanding epidemic in the Democratic Republic of the Congo, with sustained transmission, high mortality and an increasing risk of further international spread. The current outbreak is the second documented Bundibugyo virus disease outbreak in the country, after the 2012 outbreak, and the largest Ebola disease outbreak ever recorded in the Democratic Republic of the Congo irrespective of Ebola virus species. The population at greatest risk of exposure is concentrated in communities living in and moving through the health areas with active transmission.
For detailed information about the ongoing public health response actions by the Ministry of Health, WHO and partners please refer to the latest situation reports published by the WHO Regional Office for Africa: Ongoing outbreak in the Democratic Republic of the Congo | WHO | Regional Office for Africa
Health authorities in the Democratic Republic of the Congo, in collaboration with WHO and partners, are continuing to implement and coordinate extensive public health measures, including disease surveillance, laboratory testing, infection prevention and control, clinical care, community engagement, research, logistics and support for response interventions and essential health services, engaging donors and mobilizing additional resources to address critical funding gaps and sustain response operations across affected and at-risk areas. A substantial scale-up is ongoing across all response pillars to get ahead of the outbreak.
On 14 August 2026, WHO reassessed the risk of the outbreak of BVD, incorporating newly available information on the evolving situation. The risk for countries sharing land borders with the Democratic Republic of the Congo was separated from the risk for other countries in the African Region.
The risk in the Democratic Republic of the Congo was assessed as very high, the risk for countries sharing land borders with the Democratic Republic of the Congo was again assessed as high, and the risks for the rest of the African region and at the global level was again assessed as low.
For further information, please see WHO Rapid Risk Assessment-Ebola disease caused by Bundibugyo virus, Democratic Republic of the Congo v4
Based on the currently available information, WHO advises against any restriction of travel to, or trade with, affected countries. WHO continues to closely monitor and, where necessary, verify travel and trade measures in relation to this event.
The updated Temporary Recommendations issued to States Parties on 24 August 2026 underscore the importance of coordinated outbreak control, strengthened cross‑border collaboration, and sustained surveillance and preparedness to prevent further regional spread and ensure an effective public health response. Rapid recognition of cases, testing and optimized supportive care can reduce mortality, and improve community perceptions and acceptance of health care within the response.
On 7 August, the WHO Technical Advisory Group on candidate vaccine prioritization released a report regarding possible candidate vaccines for Bundibugyo virus disease. The members recommended that Ervebo, the only licensed Ebola vaccine (previously known as ebolavirus Zaire), be prioritized for inclusion in a randomized clinical trial in the context of the ongoing outbreak in the Democratic Republic of the Congo. Following a review of additional evidence on 19 August 2026, the WHO Strategic Advisory Group of Experts on Immunization (SAGE) concluded that available evidence remains insufficient to support the programmatic use of Ervebo for the prevention of BVD, and that its efficacy against BVD in humans remains unknown. WHO therefore recommends that Ervebo be used for BVD only within the context of a research protocol. Ervebo vaccination of healthcare and frontline workers is now underway. As of 6 September 2026, a total of 2007 people had been vaccinated across six health zones in three provinces: Tshopo, Bas-Uélé and Ituri.
On 2 July, a clinical trial to find effective treatments against BVD began patient enrollment on 2 July. The trial, known as the PARTNERS trial, is now open in five different clinical management facilities in Ituri province, and has enrolled over 300 people who are confirmed cases.
**Regular Information products on the outbreak of Bundibugyo virus disease
Additional information
Current outbreak: declarations and status
WHO Rapid risk assessments
Epidemiological updates and situation reports
Published Disease Outbreak News (current outbreak)
Clinical management, IPC, and occupational safety
Vaccines
Training
Prior Bundibugyo virus disease events, DRC (2012)
Background and reference
Citable reference: World Health Organization (10 September 2026). Disease Outbreak News; Bundibugyo Virus Disease, Democratic Republic of the Congo. Available at: https://www/who.int/emergencies/disease-outbreak.news.item/2026-DON617