The largest Bundibugyo Ebola outbreak on record has now killed 454 people and infected 1,481 others — and for the first time in history, a clinical trial to test treatments specifically for this strain of Ebola opened enrollment this week in the Democratic Republic of the Congo.
The World Health Organization confirmed the updated figures on July 4, 2026, covering 1,460 cases in DRC, 20 in Uganda, and one imported case in France. A U.S. citizen who contracted the virus in DRC has been medically evacuated to Germany for treatment. No cases have been confirmed in the United States.
The PARTNERS trial — an acronym for Platform Adaptive Randomised Trial for New and Repurposed Filovirus TreatmentS — enrolled its first patient on July 2, 2026, testing two antiviral candidates: MBP134 (a monoclonal antibody) and remdesivir (the antiviral used in COVID-19 treatment). It is the first randomized controlled trial ever conducted to identify effective treatments for Bundibugyo virus disease.
Why This Matters
What makes this outbreak particularly difficult to contain is the one fact that defines all of the clinical and public health challenges around it: there is no approved vaccine and no approved treatment for Bundibugyo ebolavirus.
Previous major Ebola outbreaks in DRC — particularly those in 2018–2020 — were caused by the Zaire species, for which the Ervebo vaccine and two monoclonal antibody treatments (mAb114 and REGN-EB3, the combination used in Inmazeb) have been approved and deployed. Those tools work against Zaire ebolavirus. They do not have the same evidence base for Bundibugyo.
The WHO recommended on May 28, 2026, against the use of the rVSV-ZEBOV (Ervebo) vaccine for the Bundibugyo virus, due to low evidence that it provides cross-protection. This leaves clinicians relying entirely on supportive care — fluids, fever management, and preventing secondary infections — while research teams race to establish whether any drug changes outcomes.
What We Know So Far
As of the most recent WHO Disease Outbreak News, 1,481 confirmed cases have been reported: 1,460 from DRC, 20 from Uganda, and one from France. There have been 454 deaths, including two in Uganda. At least 229 patients have recovered — 213 in DRC and 16 in Uganda.
The surge in reported cases since late June is partly explained by improved surveillance: since June 19, an additional 564 confirmed cases and 220 confirmed deaths were reported from DRC — the increase driven in part by scaling up testing and diagnostic capacity.
DRC has recorded an average of 38 new confirmed cases per day over the past two weeks, WHO Director-General Dr. Tedros Adhanom Ghebreyesus said.
Regarding the first imported European case: French authorities notified WHO on June 24, 2026, of a laboratory-confirmed case in a middle-aged male medical doctor who returned from Ituri Province, DRC. Upon arriving at Charles de Gaulle Airport on June 23, the patient self-reported symptoms to airport health authorities, prompting immediate isolation and referral to a designated high-containment healthcare facility.
The PARTNERS Trial: What It Tests and Why It Matters
The PARTNERS trial will assess whether two antiviral therapies — MBP134, a monoclonal antibody, and remdesivir — can improve survival among people diagnosed with Bundibugyo virus disease. It will also evaluate whether combining the two antivirals provides additional benefit.
MBP134 is an antibody billed as a 'pan-Ebola' candidate designed to target the four species that infect humans. Remdesivir was an important part of the COVID-19 pandemic response. PARTNERS is expected to include more than 1,000 patients, and sufficient stocks of both drugs are already in place to complete the study, according to WHO.
The U.S. donated supplies of MBP134, while Gilead has donated more than 2,000 vials of remdesivir for the trial. The trial's adaptive design also means a third priority drug — maftivimab, part of the Regeneron Inmazeb cocktail — can be added once single-agent stocks are validated.
Trial results will take months. But the opening of enrollment represents the first structured opportunity to establish an evidence base for treating a strain of Ebola that has caused human outbreaks since 2007 without ever having a treatment formally tested in a clinical trial.
Where the Risk Is Highest
Within the United States, the risk to the general public remains very low. The outbreak originated in Ituri Province in northeastern DRC and has spread to North Kivu Province and Uganda's capital Kampala.
The U.S. government has implemented entry restrictions for travelers from DRC, Uganda, and South Sudan, limiting entry to U.S. citizens and nationals only. These restrictions were renewed on June 21, 2026, and are in effect through at least July 21.
Enhanced health screening is active at U.S. airports receiving flights with connections from the affected region. The CDC's risk assessment places the likelihood of importation to the United States at approximately 1.3% over a three-month window — low but not zero, as the French and German cases demonstrate.
Healthcare workers in facilities that could receive returned travelers from affected areas are the domestic population that requires the most preparation. The CDC issued a Health Alert Network advisory on May 16, 2026, specifically calling on U.S. clinicians, laboratory staff, and public health practitioners to review evaluation protocols for viral hemorrhagic fever.
What Doctors and Experts Say
Managing this outbreak presents severe clinical and logistical hurdles. The Bundibugyo strain currently lacks an approved vaccine or targeted therapeutic, meaning clinicians must rely heavily on supportive care. Additionally, healthcare workers face intense mistrust from local populations — protesters recently set an isolation center on fire in the Nia Nia health zone, and several suspected patients fled, significantly increasing the risk of community transmission.
"Stand with science — because science is the foundation for protecting health," said WHO Director-General Dr. Tedros, invoking the agency's 2026 World Health Day theme as the PARTNERS trial opened. Dr. Tedros confirmed at his July 2 briefing that DRC's case count had accelerated significantly in the preceding two weeks and that the trial opening represented the global health community's most important immediate response option.
Infectious disease clinicians in the U.S. have emphasized that the relatively low domestic risk is contingent on continued containment efforts in DRC — a dynamic that can shift if the outbreak trajectory worsens.
What the Evidence Shows — and What It Does Not
The current imported cases in France and Germany do not represent local transmission in Europe. Both individuals were healthcare workers with direct DRC exposure who self-identified at points of entry and were immediately isolated — exactly the detection system that is designed to work.
MedicalDaily Evidence Check
- Total confirmed cases : 1,481 (as of July 4, 2026)
- Total deaths : 454
- Countries affected : DRC (primary), Uganda, France (imported), Germany (U.S. citizen, medically evacuated)
- U.S. cases : None confirmed
- Approved vaccine for Bundibugyo : None
- Approved treatment for Bundibugyo : None
- PARTNERS trial : Enrolled first patient July 2, 2026; testing MBP134 and remdesivir; expected to include 1,000+ patients
- What it does not prove : Any drug works; trial results are months away
- What readers should know : The domestic risk is low; healthcare workers in travel medicine and emergency settings need updated protocols
Who Faces the Greatest Risk?
For Americans, the risk categories are:
- Healthcare workers in facilities that evaluate returned travelers from DRC, Uganda, or neighboring countries — the highest-risk clinical group domestically
- U.S. citizens who have recently traveled to Ituri Province, North Kivu Province, or Kampala and are still within the 21-day incubation window
- Healthcare workers deployed to DRC or Uganda as part of international outbreak response missions
The general U.S. population faces very low risk. The outbreak is geographically concentrated, transmission requires direct contact with body fluids, and surveillance at points of entry is active.
Symptoms and Warning Signs to Watch For
Bundibugyo virus disease typically begins with:
- Sudden high fever
- Severe headache and fatigue
- Muscle pain and weakness
- Sore throat, followed by nausea, vomiting, and diarrhea
- In severe cases: unexplained bleeding or bruising
The incubation period is 2 to 21 days after exposure. If you have recently returned from DRC, Uganda, or South Sudan and develop any of these symptoms, do not go to a clinic or hospital without calling ahead. Contact your local or state health department immediately, describe your travel history, and follow their instructions before making any clinical contact.
What You Can Do Now
- If you have recently traveled to affected areas of DRC, Uganda, or South Sudan , monitor your temperature and health twice daily for 21 days after your return.
- Healthcare providers should review the CDC's HAN advisory and current evaluation protocols for patients presenting with febrile illness and recent travel to the affected region.
- Do not travel to Ituri Province or North Kivu Province in DRC. The CDC has issued a Level 3 Travel Health Notice — Avoid Nonessential Travel.
- If you experience symptoms after returning from an affected country, call your local health department before going anywhere. Do not drive yourself to an emergency room.
- Blood donors who have been to affected areas should defer donation for 21 days after return or until symptom-free — follow guidance from your blood donation center.
Cost and Access: What Patients Should Know
Bundibugyo virus disease testing in the United States is available at CDC's emergency laboratory and through the Laboratory Response Network in 41 states. Testing is coordinated through public health authorities at no direct cost to the patient.
The National Ebola Training and Education Center coordinates with federally designated special pathogen treatment centers — biocontainment facilities in Atlanta, Omaha, Maryland, and Montana — for any confirmed case requiring advanced treatment. These facilities are prepared for exactly this scenario.
What Happens Next
The PARTNERS trial is expected to produce initial data within the coming months. Simultaneously, vaccine development for Bundibugyo is being fast-tracked: CEPI is funding three vaccine candidates from IAVI ($3.2 million), Moderna ($50 million), and the University of Oxford ($8.6 million), none of which are yet in human trials.
U.S. entry restrictions expire July 21, 2026, and will need to be reviewed based on outbreak trajectory. MedicalDaily will update this report as PARTNERS trial progress, case totals, and U.S. travel or screening policy changes are announced.
The Bottom Line
The Bundibugyo Ebola outbreak is the worst on record for this species — and it is the first to reach European soil through travel. The absence of an approved vaccine or treatment makes it uniquely difficult to manage. The PARTNERS trial opening this week is the first clinical attempt to change that reality. For the American public, the risk remains very low; for healthcare workers in travel medicine and emergency settings, the time to review protocols is now, not after a case arrives.
