Situation at a glance
The Bundibugyo virus disease (BVD) outbreak in the Democratic Republic of the Congo and Uganda continues to evolve rapidly, with increasing case numbers, geographic spread, and ongoing cross-border transmission.
As of 27 May, a total of 906 suspected cases and 223 deaths among suspected cases have been reported in the Democratic Republic of the Congo.
As of 29 May, a total of 134 confirmed cases, including nine in Uganda, with 18 deaths among the confirmed cases, have been reported across both countries.
This is an additional 49 confirmed cases, eight confirmed deaths, 160 suspected cases and 47 suspected deaths since the last update on 21 May.
In addition, there is one confirmed case, an individual from the United States of America, who had treated patients in the Democratic Republic of the Congo and is currently receiving care in Germany.
In the Democratic Republic of the Congo, transmission is concentrated in Ituri, as well as North Kivu and South Kivu provinces, with challenges in contact tracing and follow-up, insecurity, inadequate isolation, care, and referral systems for patients complicating response efforts.
National authorities, in collaboration with WHO and partners, are implementing response measures including deployment of rapid response teams, delivery of medical supplies, strengthened surveillance, laboratory confirmation, infection prevention and control, the set-up of safe and optimized treatment centers, and community engagement.
Description of the situation
Since the last Disease Outbreak News was published on 21 May 2026, the number of suspected and confirmed cases has increased rapidly in the Democratic Republic of the Congo.
In total, 906 suspected cases, including 223 deaths among suspected cases have been reported from Democratic Republic of the Congo; and 134 confirmed cases (nine in Uganda), including 18 deaths (one in Uganda) (CFR 14%) have been reported from the two countries as of 29 May.
Additionally, a medical doctor from the United States of America who was exposed as part of their work caring for patients in the Democratic Republic of the Congo tested positive on 17 May and was transported to Germany for treatment and care.
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Democratic Republic of the Congo
Since the last update dated 21 May, an additional 42 confirmed cases including eight deaths and 160 suspected cases including 47 deaths have been reported from the Democratic Republic of the Congo.
As of 27 May 2026, a total of 125 confirmed cases including 17 deaths (CFR 14%); and 906 suspected cases including 223 deaths have been reported from 13 health zones (HZ) in Ituri (7/36 HZ), North Kivu (5/35 HZ) and South Kivu Provinces (1/34 HZ) [1].
Sixteen confirmed cases have been reported among health and care workers to date.
Epidemiological and laboratory investigations are ongoing to reclassify all suspected cases and deaths reported in the Democratic Republic of the Congo.
The outbreak remains concentrated in Ituri Province, which accounts for 88% (110) of confirmed cases.
The highest confirmed case numbers in Ituri Province are reported from Bunia (37 cases), Rwampara (33 cases), Mongbwalu (20 cases), and Nyankunde (10 cases) HZ.
Of the 17 deaths among confirmed cases in the Democratic Republic of the Congo, 10 were male (nine were over 15 years old and one under 15) and seven were female (five over 15 years old and two under 15).
A total of 774 samples have been collected as of 27 May. Of these, 648 samples (84%) have been analyzed, with 125 testing positive, representing a test positivity rate (TPR) of 19.2%. This is likely an underestimation of the actual positivity rate as over 100 samples are still awaiting testing and have been sent to Kinshasa for further analysis.
As of 27 May, 2635 contacts have been listed in Ituri and North Kivu provinces.
Security incidents against health facilities, and community resistance, have recently emerged as major operational challenges in Ituri Province, with three recent incidents reported in Mongbwalu and Rwampara HZ. These create additional risks for undetected transmission, disrupt outbreak response efforts, and reinforce the need to strengthen community protection and engagement activities
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Uganda
Since the last update dated 21 May, an additional seven confirmed cases have been reported from Uganda.
As of 29 May 2026, a total of nine confirmed cases including one death have been reported in Kampala (n=8) and Wakiso (n=1), Uganda.
Recent cases include a Ugandan driver who transported the first reported case, a Congolese health worker with linkage to the index case, a Congolese woman who travelled to Uganda for medical care, and two Ugandan health workers linked to earlier confirmed case.
As of 26 May, a total of 436 contacts linked to the cases have been identified and are under follow-up. These include close household contacts and hospital contacts where the cases were hospitalized.
Exposure risks are associated with healthcare settings and cross-border movements.
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Epidemiology
Bundibugyo virus disease (BVD) is a severe and often fatal form of 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 or items.
Transmission is particularly amplified in health-care settings when infection prevention and control (IPC) measures are inadequate, and during unsafe burial practices involving direct contact with the deceased.
The incubation period for BVD ranges from 2 to 21 days, and 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. Case fatality rates in the past two BVD outbreaks, reported in Uganda and in the Democratic Republic of the Congo in 2007 and 2012, have ranged from approximately 30% to 50%.
Differentiating BVD from other endemic febrile illnesses such as malaria is challenging without laboratory confirmation using PCR or antigen/antibody-based assays.
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.
Public health response
Health authorities in the Democratic Republic of the Congo and Uganda, in collaboration with WHO and partners, are implementing comprehensive public health measures. WHO Director-General, Dr Tedros Adhanom Ghebreyesus, traveled to the Democratic Republic of the Congo on 28 May to support the ongoing response.
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WHO risk assessment
On 22 May 2026, WHO assessed the risk of the outbreak of BVD to be very high at the national level in the Democratic Republic of the Congo, high at the regional level, and low at the global level.
The risk assessment will be continuously reassessed in the coming days based on available and shared information.
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WHO advice
On 19 May 2026, the Director-General of WHO convened the first meeting of the IHR Emergency Committee, which issued the temporary recommendations on 22 May 2026 to States Parties. These recommendations underscore the importance of coordinated outbreak control, enhanced cross‑border collaboration, and sustained surveillance and preparedness to prevent further regional spread and ensure an effective public health response
WHO advises against any restriction of travel to, or trade with, the Democratic Republic of the Congo or Uganda based on the currently available information.
WHO continues to closely monitor and, where necessary, verify travel and trade measures in relation to this event.
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[1] Data source: Centre des opĂ©rations d'urgences de sante publique (COUSP-DRC) available at : SitRep MVE N° 013/2026 – National Institute of Public Health
Citable reference: World Health Organization (29 May 2026). Disease Outbreak News; Bundibugyo Virus Disease, Democratic Republic of the Congo and Uganda. Available at https://www.who.int/emergencies/disease-outbreak-news/item/2026-DON605
Source:
Link: https://www.who.int/emergencies/disease-outbreak-news/item/2026-DON605
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