KINSHASA, November 15, 2026 — Researchers are expanding vaccine and treatment trials against the Bundibugyo strain of Ebola in the Democratic Republic of the Congo, but the country’s outbreak remains a major public-health emergency, with more than 11,000 cases recorded and nearly half of those infected reported to have died.

The latest research developments offer a route towards better protection and treatment, but they do not mean an effective vaccine or medicine is already available for this strain. The World Health Organization (WHO) says no vaccine or therapeutic has yet been specifically licensed for Bundibugyo virus disease. Candidate products are being assessed through clinical research, and the results will be needed before their safety and effectiveness can be established.

Health workers disinfecting during the 1995 Kikwit Ebola outbreak
Archive photograph of clinic disinfection procedures during the 1995 Kikwit Ebola outbreak in what is now the Democratic Republic of the Congo. Photo: Ethleen Lloyd / CDC Public Health Image Library, public domain. This is not a photograph from the 2026 outbreak. Image source.

WHO Recommends Two More Vaccine Candidates

In a November 4 announcement, WHO said expert groups had recommended adding two candidate vaccines to the ongoing Tumaini clinical trial in the DRC. They are ChAdOx1, developed by the University of Oxford with the Serum Institute of India, and Moderna’s mRNA-1469. Both were designed to target Bundibugyo virus, the strain responsible for the current outbreak.

The recommendation is notable because it is the first time vaccines specifically designed for Bundibugyo virus have been considered for evaluation during an outbreak of the disease. The candidates will enter the trial after national approvals. WHO said four vaccination rings had already been established, with additional rings being prepared.

Tumaini uses a ring-vaccination approach, in which contacts of people with confirmed Bundibugyo virus disease are enrolled. The design allows researchers to assess candidate vaccines while response teams identify and monitor people who may have been exposed. WHO said the trial is being led by the DRC’s National Institute of Biomedical Research with international research and public-health partners.

Nurse wearing personal protective equipment before entering an Ebola isolation ward in Kikwit in 1995
Archive photograph of a nurse preparing to enter an Ebola isolation ward during the 1995 Kikwit outbreak. Photo: Ethleen Lloyd / CDC Public Health Image Library, public domain. This is not a photograph from the 2026 outbreak. Image source.

Several Treatment And Prevention Studies Are Underway

Research is also progressing on potential treatments. The WHO-sponsored PARTNERS trial, launched in July, is evaluating the monoclonal antibody MBP134, the antiviral drug remdesivir and a combination of the two among patients with confirmed Bundibugyo virus disease. WHO said maftivimab would also be added to the study for evaluation as a potential treatment.

A separate post-exposure prevention study is assessing obeldesivir among people at high risk after contact with a confirmed case. These studies are important because they test whether experimental medicines can prevent infection or improve survival, rather than assuming that results from other Ebola strains will automatically apply to Bundibugyo.

Médecins Sans Frontières (MSF) and its research centre Epicentre launched the BRAVO study in September with the DRC Ministry of Health, Africa CDC and other partners. The observational study aims to enrol 20,000 frontline workers in Ituri and North Kivu to assess whether Ervebo, a vaccine licensed for the Zaire strain of Ebola, provides protection against Bundibugyo disease. The vaccine is not specifically licensed for this strain, which is why evidence from the study is needed.

A report published by Le Monde on Sunday said about 2,030 people had enrolled in the BRAVO study by October 27. It also reported that the treatment platform had administered experimental treatment to hundreds of patients, while researchers cautioned that the effect of the medicines could not yet be separated from the possibility of natural recovery. Those observations are not final trial results and should not be interpreted as proof that a treatment works.

CDC health worker incinerating medical waste used in the treatment of Ebola patients in Yambuku in 1976
Archive photograph of a health worker incinerating materials used in the treatment of Ebola patients at a Yambuku hospital in 1976. Photo: Dr. Lyle Conrad / CDC Public Health Image Library, public domain. This is not a photograph from the 2026 outbreak. Image source.

Outbreak Response Still Faces Serious Obstacles

The research effort is unfolding as the epidemic continues to strain health services. The Associated Press reported on November 15 that more than 11,000 cases had been recorded and nearly half of those infected had died. The outbreak has spread across eight provinces, while cases have also been confirmed in neighbouring countries including Uganda, Kenya and Nigeria.

AP reported that weaknesses in contact tracing and isolation have left a large proportion of new infections outside established surveillance. It also cited delayed salaries that have contributed to health-worker strikes, attacks on health facilities and concern among humanitarian organisations about whether funding is reaching frontline services. Reuters reported on November 13 that UN health officials had identified insecurity as a major obstacle, with attacks on health workers and facilities complicating access to affected communities.

These problems can undermine even promising medical research. Clinical trials need reliable diagnostic testing, timely referrals, safe treatment facilities and sustained contact with participants. Insecurity, mistrust, shortages of staff and interruptions to basic services can delay enrolment and make it harder to follow participants long enough to establish whether a vaccine or medicine is effective.

WHO said initial findings from the treatment trials are expected in the coming months, while results from the vaccine trial are expected in early 2027. Until those data are available and reviewed, candidate vaccines and treatments should not be presented as proven protection or cures for Bundibugyo virus disease.

HeadlinesXtra Analysis

The expansion of the Tumaini trial is an important scientific step because it brings Bundibugyo-specific vaccine candidates into an outbreak setting where evidence is urgently needed. The treatment studies are equally important: they test whether existing antiviral and antibody approaches can improve outcomes against a strain for which no specific treatment has been approved.

However, the scale of the outbreak shows why research cannot be treated as a substitute for public-health capacity. Vaccines and medicines can become valuable tools only if communities can reach care, health workers are paid and protected, suspected cases are tested quickly, and contact tracing is trusted. The high number of infections outside surveillance suggests that the response must strengthen local detection and community engagement alongside the trials.

The most important milestone in the coming months will not simply be the addition of more candidate products. It will be credible trial data showing whether they are safe and effective, combined with a response system capable of delivering any successful intervention fairly and at scale. Until then, the outbreak remains uncontrolled and the experimental candidates remain under investigation.

Sources And Further Reading