On 7 August 2026, Ebola cases in the Democratic Republic of the Congo (DRC) passed 4,000, according to the country's Ministry of Health. The outbreak, caused by a type of Ebola called Bundibugyo, has now reached 4,053 cases and 1,850 deaths since it was declared in mid-May 2026 Al Jazeera. On the same day, the World Health Organization (WHO) recommended starting full-scale human trials of a vaccine called Ervebo to see if it can work against this particular strain Al Jazeera.

The outbreak has been growing fast. On 30 July, WHO counted 3,605 cases and 1,587 deaths WHO. By 4 August, WHO and Africa CDC jointly reported 3,973 cases, 1,801 deaths, and 776 recoveries across 51 health zones WHO. The outbreak now spans 53 health zones across five provinces: Ituri, North Kivu, South Kivu, Haut-Uele, and Tshopo. Most cases, 87 percent, are in Ituri province, with 11 percent in neighbouring North Kivu Al Jazeera. It has been called the fastest-spreading Ebola outbreak on record. Only West Africa's 2014–2016 epidemic, which recorded more than 28,000 cases across Guinea, Liberia, and Sierra Leone, has been larger.

Ervebo is the only licensed Ebola vaccine, but it was designed for a different strain called Zaire. It has not been approved for Bundibugyo. Animal studies reviewed by WHO experts offer some hope: three of four vaccinated monkeys survived exposure to Bundibugyo, compared with one of four unvaccinated animals. An unpublished ferret study found that a research version of Ervebo gave 100 percent protection, with all unvaccinated animals dying within 10 days Al Jazeera. The Gavi vaccine alliance, which keeps a stockpile of 500,000 Ervebo doses, has made some available for the trials, and some are already in the DRC.

WHO's vaccine advisory group published a report on 7 August 2026 from its third meeting, laying out priorities for fighting this outbreak WHO. The group said a vaccine specifically designed for Bundibugyo is still the best option. Two such vaccines are in early human trials, and a third is on the way. The group warned that Ervebo may not stop transmission even if it helps prevent deaths — so expectations should be tempered Al Jazeera.

Treatments are also being tested. On 2 July 2026, WHO began a treatment trial in the DRC enrolling more than 1,000 patients, using an experimental drug from Mapp Biopharmaceutical. Results are expected to take months Reuters. As of early August, the trial was running at three facilities in Ituri province with medical partners and was showing promise Reuters. On 6 August, Africa CDC and WHO called together for urgent, community-led action to contain the outbreak WHO.

The broader context here is a set of overlapping challenges: ongoing armed conflict in the DRC, delays in detecting the outbreak early on, and the lack of medical tools designed for this specific strain. The outbreak was confirmed in the DRC and Uganda in May 2026, with Bundibugyo identified as the cause WHO. Gavi chief executive Sania Nishtar has called it the largest Ebola outbreak in DRC's history and warned it could become the largest ever recorded Al Jazeera. On 28 May, WHO urged that candidate drugs and vaccines be tested in clinical trials to gather evidence Reuters.

Looking at what this means, using Ervebo against a strain it was not built for is a calculated bet. The advisory group's preference for a Bundibugyo-specific vaccine, and its cautious language about Ervebo, suggest the animal results are promising but not enough to rely on with confidence. The logic is simple: a licensed vaccine with doses already in reserve can reach people faster than new vaccines still in early testing. But the group's warning that Ervebo might prevent deaths without stopping transmission means it could reduce the severity of the epidemic without halting its spread.

The setting itself adds difficulty. Ituri and North Kivu have been caught in armed conflict and displacement for years. Vaccination campaigns that depend on quickly finding cases, tracing contacts, and earning community trust run into trouble where government control and health services are weak. The joint call from Africa CDC and WHO for community-led action is an acknowledgment that medical tools alone cannot solve an outbreak moving this fast in this kind of environment.

For those watching the response, the key things to track are how quickly the Ervebo trial enrolls participants, whether the Mapp treatment trial in Ituri produces early signals, and how the outbreak evolves in South Kivu, Haut-Uele, and Tshopo, where its spread is still being mapped. Ervebo's safety record — established across roughly 4,000 people per WHO's vaccine safety committee — gives a foundation, but whether it works against Bundibugyo will now be tested in real time, under field conditions WHO.