Ebola Disease Caused by Bundibugyo Virus - Democratic Republic of the Congo, Kenya and Nigeria

23 October 2026

Situation at a glance

Since the publication of the previous Disease Outbreak News on 8 October 2026, the Bundibugyo virus disease (BVD) outbreak has expanded geographically in the Democratic Republic of the Congo, as well as in the African Region, with Kenya and Nigeria reporting imported cases. Sustained, high-level transmission continues in the Democratic Republic of the Congo. As of 20 October 2026, a total of 9704 confirmed cases, including 4687 deaths (crude case fatality ratio: 48.3%), have been reported across 66 health zones in eight provinces. The high proportion of deaths occurring in communities continues to highlight challenges in early case detection and timely access to appropriate care. Of the 482 deaths reported since the previous update, 307 occurred in communities and 175 in treatment centres. On 6 October 2026, the Ministry of Health of Kenya reported the first laboratory-confirmed imported case of BVD in Kenya in an individual who had travelled from the Democratic Republic of the Congo to Kenya via Uganda. As of 20 October 2026, a total of nine cases of BVD including one death, has been reported in Kenya. The eight additional cases are all known contacts of the first imported case. There is currently no evidence of wider community transmission. On 20 October 2026, Nigeria confirmed an imported case in the Federal Capital Territory Abuja in a patient who had travelled from Uganda to the country. The patient is currently in isolation and receiving medical care. Further investigations are ongoing to better understand the complete travel history and the possible source of exposure. These developments underscore the need for sustained readiness in the region, including cross-border surveillance, points of entry monitoring, timely case detection and coordinated preparedness and response measures. WHO advises against any restriction of travel to, or trade with, affected countries.

Description of the situation

Since the previous Disease Outbreak News was published on 8 October 2026, additional confirmed cases and deaths have been reported in the Democratic Republic of the Congo.

Cases have been reported in five countries since the declaration of the outbreak on 15 May 2026: the Democratic Republic of the Congo, Uganda, France, and more recently, Kenya and Nigeria. Nigeria is the fifth country affected by the ongoing outbreak, highlighting the continued risk of cross-border transmission.  

Democratic Republic of the Congo

An additional 976 confirmed cases, including 482 confirmed deaths, have been reported in the Democratic Republic of the Congo since the previous Disease Outbreak News was published.

In the most recent 24-hour period, as of 20 October, 67 new confirmed cases were reported, with Ituri accounting for 37 cases, Nord Kivu for 29, and Tshopo for one case. No new cases were reported in Bas-Uélé, Haut-Uélé, Nord Ubangi, Sud Kivu or Sud-Ubangi during that period.

As of 20 October, cumulative confirmed cases have reached 9704, including 4687 deaths and 2595 recoveries. The overall crude CFR is 48.3%.

Confirmed cases have now been identified in 66 health zones across eight provinces. Fifty of the 66 affected zones reported at least one new case during the preceding 21 days, while 16 reported no recent cases. Mandima, Beni and Bunia have reported the highest number of cases and deaths in the preceding 21 days. Ituri remains the most extensively affected province, with 28 of 36 health zones reporting cases during this outbreak, followed by Nord Kivu (17/34), Haut-Uélé (7/13), Tshopo (7/23), Bas-Uélé (4/11), Sud Kivu (1/34), Sud-Ubangi (1/16) and Nord-Ubangi (1/11). Nord-Ubangi is the most recently affected province reporting three confirmed cases including one death and Dakwa in Haut-Uélé is the most recently affected health zone.

Geographical distribution of confirmed BVD cases in DRC

Ituri remains the epicentre, with 7040 cumulative confirmed cases and 3271 deaths. Nord Kivu follows with 2146 confirmed cases and 1199 deaths, and continues to record the highest provincial CFR, at 55.9%. Haut-Uélé has reported 421 cases and 183 deaths, while Tshopo has recorded 76 cases and 27 deaths. The less-affected provinces continue to report substantially fewer cases, but transmission persists in several of them. The continued occurrence of cases across multiple provinces shows that the outbreak remains geographically active even as intensity varies between health zones.

Out of 30 130 contacts under follow-up across six provinces, 24 017 were seen in the last 24 hours corresponding to a follow-up rate of 79.7%, up from 77.8% the previous day, but remaining below the required threshold of 95.0%. Two provinces were at or above the 95.0% threshold: Bas-Uélé (98.9%; 740/748) and Sud-Ubangi (97.3%; 109/112). Four provinces were below the threshold: Haut-Uélé (89.9%; 1286/1430), Ituri (92.8% (6382/6879), with 7 contacts becoming suspected cases, Tshopo (83.7%; 1077/12 086) and Nord-Kivu (73.3%; 14 423/19 675), with performance in Nord-Kivu remaining insufficient. Strengthened contact follow-up is required, particularly in provinces below the target, to achieve the minimum threshold of 95%.

Confirmed deaths in DRC

Kenya

On 6 October 2026, the Ministry of Health of Kenya reported its first laboratory-confirmed imported case of BVD in an adult male who had travelled from the Democratic Republic of the Congo via Uganda by road and arrived in Nairobi on 3 October by air. The case had been ill with other comorbidities for approximately one month and received care at several hospitals in the Democratic Republic of the Congo. He was isolated upon arrival at a hospital in Nairobi. Samples collected on 5 October tested positive for Bundibugyo virus at two national laboratories. Despite supportive care, the patient died on 5 October and was given a safe and dignified burial on 6 October.

As of 20 October 2026, a total of nine cases, including one death, has been reported in Kenya.  All eight secondary cases are epidemiologically linked to the imported index case and associated with one cluster. They include four family members and four health and care workers. All new cases were under quarantine at the time of symptom onset and are currently in isolation and receiving appropriate supportive care and treatment at two designated facilities.

There is currently no evidence of transmission outside this cluster.

As of 20 October, all of the 135 contacts have been traced and quarantined.

Number of confirmed cases in Kenya

Nigeria

On 20 October 2026, Nigeria reported one laboratory-confirmed imported case of BVD in the Federal Capital Territory Abuja, becoming the fifth country to detect the virus since the outbreak was declared in the Democratic Republic of the Congo on 15 May 2026. The case developed symptoms on 7 October, four days after arriving in Nigeria, sought care in Abuja on 11 October and tested positive for Bundibugyo virus on 20 October 2026. The case is currently in isolation and receiving medical care.

As of 20 October, 44 contacts had been identified and are being monitored. National authorities, with support from WHO and partners, have intensified contact tracing, case investigation and infection prevention and control measures, including the provision of essential supplies and personal protective equipment for health workers. Investigations are ongoing to establish the likely source of infection and reconstruct the travel and exposure history. WHO has urged countries across the region to strengthen surveillance, laboratory diagnostic capacity, rapid response readiness and cross-border preparedness to mitigate the risk of further transmission.

Epidemiology

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 initially 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 infection prevention and control (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 CFR from the previous 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. Outbreak control relies on rapid case identification and investigation, 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 virus species. The population at greatest risk of exposure is concentrated in communities living in and moving through the health areas with active transmission. 

Public health response

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.

Democratic Republic of the Congo

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. These include disease surveillance; laboratory testing; IPC; clinical care; community engagement; research; logistics; and support for response interventions and essential health services, including for the ongoing concurrent humanitarian crisis; 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 23 October, the TUMAINI vaccine trial was launched, with first participants enrolled in Bunia. TUMAINI is a pivotal Phase 2/3 clinical trial of vaccine candidates against Bundibugyo virus (BDBV). The trial is an important step towards generating the evidence needed to better protect people against BVD and prevent future outbreaks. WHO is actively supporting the trial, along with partners, with technical, scientific and operational expertise.

Kenya

Health authorities in Kenya have implemented safe and dignified burial measures following the BVD-related death in Nairobi, while 135 contacts are currently under quarantine. Kenya has maintained a high level of Ebola preparedness since the outbreak began in the Democratic Republic of the Congo in May 2026; as of 22 October, 709 093 travellers have been screened, 461 samples tested across five laboratories. Kenyan authorities are also coordinating with counterparts in Uganda and the Democratic Republic of the Congo to establish the individual’s movements in Uganda and implement any necessary public health measures.

Nigeria

The National and State incident management system has been activated by the Nigeria Centre for Disease Control and Prevention to coordinate response.  WHO and partners are working closely with health authorities to strengthen control measures, including case investigation, contact tracing, infection prevention and control, and provision of essential supplies including personal protective equipment for health workers. Nigeria has maintained a high level of alert for BVD since the outbreak began in the Democratic Republic of the Congo in May 2026. 

WHO risk assessment

On 14 August 2026, WHO reassessed the risk of the outbreak of BVD. 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 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.

In light of the evolving situation and newly available information, the rapid risk assessment is currently being revised to reassess the risk in affected countries, the African region and globally.  

WHO advice

Based on the currently available information, WHO advises against any restriction of travel to, or trade with, affected countries.

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.