Determination of a public health emergency of international concern, including a pandemic emergency of the International Health Regulations (2005) (IHR), the Director-General of the World Health Organization (WHO), after having consulted the States Parties where the event is known to be currently occurring, is hereby determining that the Ebola disease caused by Bundibugyo virus in the Democratic Republic of the Congo and Uganda constitutes a public health emergency of international concern (PHEIC), but does not meet the criteria of pandemic emergency, as defined in the IHR.

The Director-General of WHO expresses his gratitude to the leadership of the Democratic Republic of the Congo and Uganda for their commitment to take necessary and vigorous actions to bring the event under control, as well as for their frankness in assessing the risk posed by this event to other States Parties, hence allowing the global community to take necessary preparedness actions.

In his determination the Director-General of WHO has considered, inter alia, information provided by the States Parties - the Democratic Republic of the Congo and Uganda - scientific principles as well as the available scientific evidence and other relevant information; and assessed the risk to human health, the risk of international spread of disease and of the risk of interference with international traffic.

The Director-General of WHO considers that the event meets the criteria of the definition of PHEIC, contained in Article 1 - Definitions of the IHR, for the following reasons:

1. The event is extraordinary for the following reasons:

As of 16 May 2026, eight laboratory-confirmed cases, 246 suspected cases and 80 suspected deaths have been reported in Ituri Province of the Democratic Republic of the Congo across at least three health zones, including Bunia, Rwampara and Mongbwalu. In addition, two laboratory confirmed cases (including one death) with no apparent link to each other have been reported in Kampala, Uganda, within 24 hours of each other, on 15 and 16 May 2026, among two individuals travelling from the Democratic Republic of the Congo. A further case reported on 16 May, an individual returning from Ituri to Kinshasa, has tested negative for Bundibugyo virus on confirmatory testing by INRB, and is therefore not considered a confirmed case.

Unusual clusters of community deaths with symptoms compatible with Bundibugyo virus disease (BVD) have been reported across several health zones in Ituri, and suspected cases have been reported across Ituri and North Kivu. In addition, at least four deaths among healthcare workers in a clinical context suggestive of viral haemorrhagic fever have been reported from the affected area raising concerns regarding healthcare-associated transmission, gaps in infection prevention and control measures, and the potential for amplification within health facilities.

There are significant uncertainties to the true number of infected persons and geographic spread associated with this event at the present time. In addition, there is limited understanding of the epidemiological links with known or suspected cases.

However, the high positivity rate of the initial samples collected (with eight positives among 13 samples collected in various areas), the confirmation of cases in Kampala, the increasing trends in syndromic reporting of suspected cases and clusters of deaths across the province of Ituri all point towards a potentially much larger outbreak than what is currently being detected and reported, with significant local and regional risk of spread. Moreover, the ongoing insecurity, humanitarian crisis, high population mobility, the urban or semi-urban nature of the current hotspot and the large network of informal healthcare facilities further compound the risk of spread, as was witnessed during the large Ebola virus disease epidemic in North Kivu and Ituri provinces in 2018-19. However, unlike for Ebola-zaire strains, there are currently no approved Bundibugyo virus-specific therapeutics or vaccines. As such, this event is considered extraordinary.

2. The event constitutes a public health risk to other States Parties through the international spread of disease. International spread has already been documented, with two confirmed cases reported in Kampala, Uganda on 15 and 16 May following travel from the Democratic Republic of the Congo. Both confirmed cases were admitted to intensive care units in Kampala. Neighboring countries sharing land borders with the Democratic Republic of the Congo are considered at high risk for further spread due to population mobility, trade and travel linkages, and ongoing epidemiological uncertainty.

3. The event requires international coordination and cooperation to understand the extent of the outbreak, to coordinate surveillance, prevention and response efforts, to scale up and strengthen operations and ensure ability to implement control measures.

The Director-General of WHO, under the provisions of the IHR, will be convening an Emergency Committee, as soon as possible to advise, inter alia, on the proposed temporary recommendation for States Parties to respond to the event.

The WHO advice is enumerated below and will be subject to further refinement as appropriate after having considered the advice from the Emergency Committee and issuing of Temporary Recommendations.

From World Health Organization