The machine was right
When people in Ituri started dying with high fever and bleeding, their samples went to the Provincial Public Health Laboratory in Bunia and into a . The machine said negative.
Days later the same samples came back positive on a that looks for every filovirus at once, run in a reference laboratory. On 22 May the World Health Organization wrote the sentence flat: the GeneXpert platform cannot detect Bundibugyo virus.
The cartridge was not broken. It was looking for sequences from Zaire ebolavirus, because Zaire ebolavirus is what it was designed for, and the samples from Bunia did not contain Zaire ebolavirus. Confirmation and isolation were delayed. The outbreak was found so late that it began with more cases than any Ebola outbreak on record.
The GeneXpert platform cannot detect Bundibugyo virus.World Health Organization, Disease Outbreak News, 22 May 2026
Three doors
Behind these doors sit the three defences the world has against Ebola: a test, a vaccine, a drug. Choose which kind of Ebola arrives.
| Species | Routine field test | Licensed vaccine | Approved drug |
|---|---|---|---|
| Zaire | yes | yes | yes |
| Sudan | no | no | no |
| Bundibugyo | no | no | no |
| Taï Forest | no | no | no |
The flat line is the negative result, the same trace as in the plot at the top.
Four kinds of Ebola make people ill. One of them has all three doors open.
The routine field test is the GeneXpert Ebola cartridge, built for Zaire. For Bundibugyo, the regulatory door stays shut: Ervebo is not licensed and clinical protection has not been demonstrated. On 7 August 2026, WHO recommended taking it directly into a Phase III study in the current outbreak after new non-human-primate, ferret and pseudovirus-neutralisation evidence suggested possible cross-protection. The approved drugs are Inmazeb and Ebanga, both for Zaire only.
A drug is only proved during an outbreak
Ervebo, Inmazeb and Ebanga were approved on the strength of studies run on people during outbreaks. That is how anyone finds out whether an Ebola vaccine or treatment works: you give it to people who have the disease or are about to be exposed to it, and you compare what happens to them. There is no other place and no other moment to do it.
Ervebo exists because the West African epidemic between 2013 and 2016 left more than 11,000 dead and, with them, enough sick people for a trial. Inmazeb and Ebanga came out of the 2018 to 2020 outbreak in DR Congo.
Both previous Bundibugyo outbreaks were too small for that. The first, in Uganda in 2007 and 2008, had 131 reported cases and 42 deaths. The second, in DR Congo in 2012, had 62 cases and 34 deaths. There were never enough sick people to prove anything, and never enough well people for a manufacturer to sell to.
There is a European document that says this out loud. When the European Medicines Agency recommended the two-dose Ebola vaccine Zabdeno and Mvabea in May 2020, it wrote that the authorisation was granted under exceptional circumstances „because the applicant was able to demonstrate that it is not possible to conduct a randomised controlled study that might generate comprehensive clinical data on the efficacy of the new Ebola vaccine even after authorisation”. The regulator wrote down the trap in 2020 and licensed the product anyway.
Nobody ever bought it. On 1 May 2026 the European Commission withdrew the authorisation at the manufacturer’s request, for commercial reasons. Fourteen days later, DR Congo declared an Ebola outbreak.
| Product | Species covered | Status |
|---|---|---|
| Ervebo | Zaire | authorised in the EU since November 2019 |
| Zabdeno and Mvabea | Zaire | EU authorisation withdrawn on 1 May 2026 |
| Inmazeb | Zaire | approved in the United States, not in the EU |
| Ebanga | Zaire | approved in the United States, not in the EU |
The world’s filovirus kit is not a map of the dangerous viruses. It is a register of the outbreaks that grew large enough to be used as proof.
The window
A treatment can only be proved while there are patients who can enter a trial.Every dot is one reported case.The first two outbreaks ended at 131 and 62 cases.There is no universal threshold: the number needed depends on the treatment, mortality and trial design.
2 July 2026PARTNERS opened in Bunia on 2 July 2026. The epidemiological situation reported for 1–2 July contained 1,481 confirmed cases in DR Congo, Uganda and France.
131 reported cases. 42 deaths.
62 reported cases. 34 deaths.
5,375 confirmed cases and 2,557 confirmed deaths in the DRC. DRC INSP/government data run through 20 August.
2 July: PARTNERS begins enrolling patients.
The third outbreak created the first window in which a trial could begin.
The 2007 and 2012 figures are reported cases from the US CDC. For the current situation the DRC’s INSP and government report 5,375 confirmed cases and 2,557 confirmed deaths, with data through 20 August. The daily series may be revised retrospectively.
Success destroyed the evidence
4years between the drug and the question still unanswered
In 2022 Uganda had an outbreak of Sudan ebolavirus. There was no approved treatment for Sudan either, so some patients were given MBP134, a pair of antibodies designed to cover several ebolavirus species at once. It was given , outside any trial, because there was nothing else to give.
Uganda stopped the outbreak faster than anyone expected. The outbreak ended before anyone could find out whether the drug had worked.
In July 2026 MBP134 entered the first trial that tests it in patients, in Bunia. Same drug. Same question. Four years in between, and it took another outbreak.
What is being built now
Day 98of 100Day 0 · 17 May 2026Day 100 · 25 August 2026
A clock started when WHO declared the international emergency on 17 May. The target is called the 100 Days Mission, and it asks for tests, treatments and vaccines against a new pathogen to exist within a hundred days of that declaration. Day 100 falls on 25 August 2026; this snapshot is Day 98.
| Species | Rapid test in the field | Licensed vaccine | Approved treatment |
|---|---|---|---|
| Zaire | GeneXpert cartridge | Ervebo | Inmazeb, Ebanga |
| Sudan | none | none | none |
| Bundibugyo | RADI kit, under validation | none | none |
| Taï Forest | none | none | none |
The flat line is the negative result, the same trace as in the plot at the top. Here it means nothing exists.
- On 2 July the first patient was enrolled in Bunia into PARTNERS, the trial testing MBP134 and remdesivir, separately and together.
- On 14 July EBO-PEP began, giving obeldesivir, a drug taken by mouth, to people who have been exposed to the virus.
- On 1 June, CEPI put money behind three candidate vaccines: up to 3.2 million dollars for IAVI, 8.6 million for Oxford with the Serum Institute of India, 50 million for Moderna.
- On 13 July the University of Oxford announced the world’s first human trial of a Bundibugyo vaccine. Fifty healthy volunteers between 18 and 55, in Oxford. The announcement counts 57 days since the emergency was declared.
- On 7 August WHO’s technical group recommended taking Ervebo directly into a Phase III study in the current outbreak to test possible cross-protection. Ervebo is not yet licensed for Bundibugyo.
- 22 May–22 August · IHR Temporary Recommendations. The set issued by WHO on 22 May reached the automatic three-month limit under the International Health Regulations. The Emergency Committee met again on 18 August; when checked on 23 August, WHO’s committee page did not include revised or extended recommendations. The international emergency has a separate legal status and remains in force.
- 21 August · the first doses reach DR Congo. More than 16,000 Ervebo doses arrived in Kinshasa. The DRC Ministry of Health and ACP give 16,520; AP and AFP reported 16,250. ACP describes this shipment as part of 50,120 doses expected between 21 and 24 August. WHO allocated 70,000 doses in total: 20,000 for the Phase III trial and 50,000 for frontline and health workers.
- 22 August · available stock is smaller than the allocation. INSP’s director says the DRC currently has 20,750 doses available: 20,000 for the Phase III trial and 750 for frontline workers. The first announced strategy is a vaccination belt around Ituri to limit spread towards Tshopo, Haut-Uele and Bas-Uele. The sources reviewed do not yet confirm administration or the start of the trial. Ervebo remains unlicensed for Bundibugyo, and its clinical effectiveness against this species has not been demonstrated.
On that same 13 July, at Rwampara general hospital inside the epicentre, epidemiologists, case investigators, drivers and gravediggers went on strike because they had not been paid since the outbreak began. On Wednesday staff at Bunia general hospital struck too and blocked the entrance. Confirmed cases were passing 2,000 that week, with 754 dead.
The Oxford trial runs on healthy volunteers in a country with no Ebola. It shows whether that candidate is safe and whether it raises an immune response. Whether it protects anyone can only be learned where the disease is, which means Ituri, during the outbreak. Ervebo is at a different stage: WHO recommends taking it directly into a study in this outbreak, but it is not licensed or proven for Bundibugyo. If the outbreak is stopped before the Oxford study can answer the protection question, that candidate remains unlicensed. Oxford delivered in 57 days. The structure it delivered into is the part that does not hold.
If too few people have your disease, nobody can prove a treatment works, so nobody makes one. Ebola is the most violent version of the logic that decides whether a drug exists for a rare disease on a children’s ward in Bucharest or in Bristol.
Sources
What this is and what it is not
Evidence was searched to 23 August 2026. This covers the regulatory position in the European Union and the United States. There was no clinical review.
What is written here is public information, not medical advice. Anyone who develops a fever after travelling in an area with Ebola should call ahead and say where they have been before walking into a waiting room.
What kinds of claim are here
- documented facthas a primary source, listed below
- a number that movescarries its date beside it
- editorial inferencejoins documented facts and is written as such
The outbreak
- World Health Organization, Disease Outbreak News no. 603, 22 May 2026The GeneXpert platform cannot detect Bundibugyo virus. DR Congo’s 17th Ebola outbreak.
- World Health Organization, External Situation Report 13, 9 August 20264,381 confirmed cases and 2,011 confirmed deaths in the DRC; transmission remains intense and expanding.
- European Centre for Disease Prevention and Control, Ebola situation, updated 21 August 2026Relays DRC data through 19 August and identifies the national authority as the source; the page is updated every weekday.
- DRC government and INSP, situation report no. 98, data through 20 August 20265,375 confirmed cases and 2,557 confirmed deaths; figures published by the Congolese authorities and relayed by news agencies.
- World Health Organization, Disease Outbreak News no. 612, 3 July 20261,481 confirmed cases in the situation reported for 1–2 July.
- World Health Organization, Disease Outbreak News no. 613, 17 July 2026Figures to 15 July, health workers infected, cases treated in France and Germany.
- World Health Organization, Disease Outbreak News no. 614, 1 August 2026Data through 30 July: 3,605 cases and 1,587 deaths in the DRC, 3,626 and 1,589 across the outbreak; the largest Ebola outbreak recorded in the DRC. Uganda declared local transmission over.
- World Health Organization, emergency declaration, 17 May 2026The date of the public health emergency of international concern.
- World Health Organization, IHR Temporary Recommendations, 22 May 2026The Temporary Recommendations issued after the Emergency Committee’s first meeting.
- World Health Organization, questions and answers on the IHR and Emergency CommitteesTemporary Recommendations automatically expire three months after issuance.
- World Health Organization, opening of the second Emergency Committee meeting, 18 August 2026The Director-General asks the committee for advice on the recommendations needed for the continuing epidemic.
- World Health Organization, Bundibugyo Emergency Committee pageWhen checked on 23 August, the page did not list a second-meeting statement revising or extending the recommendations.
- World Health Organization, rapid risk assessment, 20 August 2026Risk remains very high in the DRC, high for neighbouring countries, and low at regional and global levels.
- Africa CDC, continental emergency declaration, 18 May 2026Public health emergency of continental security.
- Médecins Sans Frontières, outbreak response pageFigures as of 21 July 2026 and the May timeline.
- Associated Press, via Euronews Health, 24 July 2026Patients isolated or hospitalised, contact tracing, the words of Trish Newport.
- Al Jazeera, 15 July 2026The strike at Rwampara and Bunia, and that week’s figures.
- Social Science in Humanitarian Action Platform, Ituri context 2026Armed conflict, displacement, gold mining, health system capacity.
The detection gap
- IPPS, Ebola (Bundibugyo) Day 15, 1 June 2026The negative results at the Bunia laboratory, Altona pan-filovirus tests, the RADI kit, the Africa CDC review of rapid antigen tests.
- IPPS, Ebola (Bundibugyo) Day 45, 1 July 2026Current status of diagnostics, therapeutics and vaccines, and what still does not exist.
Vaccines and treatments
- World Health Organization, emergency guidance on the licensed vaccine, 28 May 2026Ervebo should not be used outside carefully designed research settings.
- World Health Organization, guidance on Ervebo, B09772Ervebo is authorised for Zaire ebolavirus, not Bundibugyo; animal data do not justify programmatic use in this outbreak.
- World Health Organization, Technical Advisory Group on Candidate Vaccine Prioritization, 7 August 2026Ervebo is recommended for direct inclusion in a Phase III study in the current outbreak to test possible cross-protection.
- World Health Organization and Africa CDC, Ervebo allocation, 20 August 202670,000 doses allocated: 20,000 for the Phase III trial and 50,000 for frontline and health workers.
- Agence Congolaise de Presse, first Ervebo shipment, 22 August 202616,520 doses reached Kinshasa; 50,120 doses expected between 21 and 24 August.
- Associated Press, first Ervebo shipment reaches DR Congo, 22 August 2026AP and AFP report 16,250 doses; the difference from the Congolese figure of 16,520 remains unresolved.
- Le Potentiel, remarks by the INSP director, 22 August 2026First available stock of 20,750 doses: 20,000 for the trial and 750 for frontline workers; vaccination-belt strategy around Ituri.
- World Health Organization, expert advice on candidates, 28 May 2026The prioritised therapeutics and vaccines.
- World Health Organization, PARTNERS trial opens, 2 July 2026First patient enrolled; adaptive trial of MBP134 and remdesivir, separately and together.
- ANRS Maladies infectieuses émergentes, INRB and ALIMA, EBO-PEP launch, 14 July 2026Obeldesivir as post-exposure prophylaxis.
- University of Oxford, world’s first Phase I trial, 13 July 2026ChAdOx1 BDBV, fifty volunteers, 57 days after the emergency was declared.
- University of Oxford, first participant vaccinated, 24 July 2026The first participant received a dose in the Phase I ChAdOx1 BDBV trial, the first human trial of a Bundibugyo-specific vaccine.
- ClinicalTrials.gov, NCT07737717, Moderna trial registryClinical trial of the mRNA-1469 vaccine candidate against Bundibugyo virus disease.
- CEPI, funding for three candidate vaccines, 1 June 2026The amounts for IAVI, Oxford with the Serum Institute of India, and Moderna.
- European Medicines Agency, Ervebo pageIndication for disease caused by Zaire Ebola virus.
- European Medicines Agency, Zabdeno and Mvabea pagesAuthorisation withdrawn on 1 May 2026 at the holder’s request, for commercial reasons.
- European Medicines Agency, press release, 29 May 2020Authorisation under exceptional circumstances and the regulator’s written reason.
History and virology
- US CDC, History of Ebola OutbreaksUganda 2007: 131 reported cases, 42 deaths. DR Congo 2012: 62 cases, 34 deaths.
- Towner JS et al., PLOS Pathogens 4(11): e1000212, 2008The surface glycoprotein differs between Bundibugyo and Zaire by more than 35% at the amino acid level.
- Mbala-Kingebeni P., Ssewanyana I. et al., Virological.org, from 18 May 2026The initial genomes from this outbreak and the species identification.
Current as of 23 August 2026. Outbreak figures are tied to the date written beside them and may be revised.