A rare and deadly Ebola strain has infected an American doctor in eastern Democratic Republic of the Congo, raising fears of a wider international outbreak.

The infection involves the Bundibugyo ebolavirus variant, a rare Ebola strain with no approved vaccine or treatment. Following the growing number of cases, the World Health Organization declared the outbreak a Public Health Emergency of International Concern (PHEIC).

American Doctor Contracts Virus

Health officials confirmed that Dr Peter Stafford, an American physician working with the Christian mission organisation Serge, tested positive for Ebola in Bunia, a city in Congo’s conflict-hit Ituri province.

Dr Stafford treated infected patients at a local hospital before developing severe symptoms. Authorities are now transferring him to Germany for specialised treatment in a secure biocontainment facility.

Officials said at least six other Americans had direct exposure to the virus.

Authorities classified three people as “high-risk contacts.” At least one person has already developed symptoms and remains in isolation. Dr Stafford’s wife, who also worked at the hospital, is under close monitoring.

Testing Failure Delayed Response

Investigators said a major testing mistake delayed the emergency response and allowed the virus to spread. The first deaths appeared on April 24. However, officials did not declare a public health emergency until mid-May.

Local laboratories tested samples only for the Zaire ebolavirus strain, which caused most previous Ebola outbreaks. When those tests came back negative, health workers wrongly believed patients had a tropical fever instead of Ebola.

Officials discovered the real cause only after they sent samples to the National Institute of Bio-Medical Research in Kinshasa. Scientists there identified the Bundibugyo strain through genetic sequencing.

Unlike the Zaire strain, the Bundibugyo variant has no approved vaccines or treatments. Existing emergency stockpiles cannot effectively fight the outbreak.

Virus Reaches Major Cities

The delay gave the virus time to spread from remote mining camps into crowded cities. Authorities confirmed cases in Goma, a major eastern city with more than two million residents. Officials also detected infections in Kinshasa and Kampala, the capital of neighboring Uganda.

At the same time, violence in eastern Congo continues to disrupt emergency medical work.

Armed militia groups have attacked healthcare workers dozens of times since January 2025. The unrest may slow plans announced by Congolese Health Minister Samuel Roger Kamba to open three new treatment centres.

US Issues Travel Warning

The Centers for Disease Control and Prevention issued a Level 2 Travel Advisory for the affected region. US authorities also introduced stricter screening measures for travellers arriving from outbreak zones.