Imported case in Nigeria, cluster in Kenya and continued expansion in the DRC
On 15 May 2026, the Ministry of Public Health of the Democratic Republic of the Congo (DRC) declared the country’s 17th Ebola disease outbreak, caused by Bundibugyo virus, in Ituri Province, following laboratory confirmation in eight samples; the presumed index case had symptom onset in late April 2026. On 17 May, WHO determined that the event constituted a public health emergency of international concern (PHEIC).
As of 21 October (data up to 20 October), ECDC reports 9,704 confirmed cases, including 4,687 related deaths, in the DRC across 66 of 178 health zones in eight provinces (crude case fatality ratio [CFR] ≈48%); the eighth province, Nord-Ubangi, was affected on 18 October. This makes it the largest Bundibugyo virus disease outbreak on record and the second-largest Ebola disease outbreak after the 2014–2016 West African epidemic.
Uganda reported 20 confirmed cases between May and June (last confirmed case reported 21 June), and its outbreak was declared over by WHO and Africa CDC on 27 August. Since October, cases have been exported to Kenya (single cluster, nine cases) and Nigeria (one case), while four patients infected in the DRC have been managed in high-level isolation units in Europe, all of whom recovered without reported secondary transmission (Table 1).
Cases are listed by country where they were diagnosed or managed; rows should not be summed, as WHO counts the medically evacuated case managed in the Netherlands within the DRC total. DRC figures as of 21 October (data up to 20 October); Kenya figures as of 22 October; Nigeria as reported 20–22 October (16). MSF, Médecins Sans Frontières; LUMC, Leiden University Medical Center; PHEIC, public health emergency of international concern; HLIU, high level isolation unit.
Bundibugyo virus disease continues to expand geographically, with a newly confirmed imported case in Nigeria, an ongoing cluster in Kenya, and spread to an eighth province in the Democratic Republic of the Congo (DRC).
Nigeria confirmed its first imported case on 20 October in Abuja. The patient travelled from Uganda on an international flight (arriving on or around 3 October; media sources report transit through Addis Ababa, Ethiopia), developed symptoms on 7 October and sought care at a private health facility on 11 October, but laboratory confirmation was obtained only on 20 October. She is currently in isolation. Forty-four contacts, including healthcare workers, patients, caregivers and travel contacts, have been identified for monitoring/quarantine. Nigerian authorities report that she was asymptomatic on arrival; symptom onset occurred four days after arrival. Although Nigerian authorities reported no confirmed travel to the DRC, the Ugandan Minister of Health stated on 20 October that she had travel history to the DRC (16).
Kenya reported a ninth confirmed case on 20 October. The patient, a 24-year-old relative of the index case, developed symptoms while already in quarantine and tested positive on 19 October. All nine cases reported to date remain within a single epidemiological cluster, with no confirmed transmission beyond this chain. One death has occurred, involving the index case. The eight secondary cases, reported between 14 and 20 October, comprise four relatives and four healthcare workers; 135 contacts had been traced as of 22 October (16).
DRC continues to report substantial transmission. As of 21 October (data up to 20 October), ECDC reports 9,704 confirmed cases, including 4,687 related deaths, across 66 of 178 health zones in eight provinces; 67 new confirmed cases were reported since the previous update (Ituri 37, Nord-Kivu 29, Tshopo 1). Ituri remains the most affected province (7,040 cases; 3,271 deaths), followed by Nord-Kivu (2,146; 1,199) and Haut-Uélé (421; 183). Contact follow-up stands at 79.7% (16). On 18 October, cases were also confirmed in Wapinda health zone, Nord-Ubangi, extending the outbreak to an eighth province and to an area bordering the Central African Republic.
The Nigerian case raises an important epidemiological question, as the patient’s travel history has not yet been fully established. Uganda reported its last confirmed case on 21 June, and WHO declared the outbreak over on 27 August (9, 16). Given symptom onset on 7 October, acquisition in Uganda would imply unrecognised transmission almost three months after the last confirmed case. Alternatively, infection may have been acquired in the DRC, as suggested by the Ugandan Minister of Health (16), although Nigerian authorities initially reported no confirmed travel to the DRC (6). Neither possibility can currently be excluded.
The interval between the patient's presentation to a healthcare facility and laboratory confirmation also highlights the potential for healthcare-associated exposure when Bundibugyo virus disease is not initially suspected.
Continued geographic expansion in the DRC, including towards areas bordering neighbouring countries, increases the importance of preparedness beyond currently affected areas.
ECDC (23 October) assesses the likelihood of infection as low for people from the EU/EEA living in or travelling to affected areas, and as very low for people living in the EU/EEA, given the very low likelihood of importation and secondary transmission. ECDC also considers it likely that the outbreak in the DRC is larger than currently reported (16, 17).
Clinicians should maintain awareness of Bundibugyo virus disease in patients with a compatible acute febrile illness and relevant recent travel or epidemiological exposure.
Early illness may be non-specific. A detailed travel and exposure history is therefore essential, including travel within affected countries, contact with suspected or confirmed cases, healthcare exposure and possible participation in funeral or burial activities.
Where viral haemorrhagic fever is considered possible:
There is currently no licensed vaccine or specific licensed therapy for Bundibugyo virus disease.
The likely place and route of acquisition of the Nigerian infection have not yet been established. It is also too early to determine whether secondary transmission has occurred in Nigeria.
The Kenyan cases remain within a single reported transmission chain, but continued contact monitoring is required.
DRC-reported figures on confirmed cases and deaths are under continuous review and harmonisation (16); the WHO weekly situation report 22 (data as of 11 October) predates the current data cut-off.
ESCMID Emerging Infections Subcommittee (EIS) Information current as of 23 October 2026