The Ebola vaccine developed against the Zaire strain may not prevent Bundibugyo infections, but Africa CDC says it appears to save lives, as vaccinated people develop only mild symptoms, while every death recorded so far has been among the unvaccinated.
Fear that the Bundibugyo Ebola virus tearing through eastern Democratic Republic of Congo (DRC) may be mutating has pushed the World Health Organization (WHO) and the Africa Centres for Disease Control and Prevention (Africa CDC) into an unusual joint call for emergency community action.
In just 12 weeks since the outbreak was first declared on May 15, 2026, confirmed cases have passed 4,000 and deaths have risen past 1,800, a pace that has turned a familiar public health emergency into what Africa CDC now calls an unprecedented crisis.
The outbreak is driven by the Bundibugyo strain of Ebola, spreading through eastern DRC faster than any recent epidemic. During Africa CDC’s weekly briefing, held with senior WHO experts, researchers and laboratory specialists on August 6, 2026, Director-General Dr Jean Kaseya said the numbers were already out of date.
“We have already achieved 4,000 confirmed cases and 1,800 deaths,” he said, noting the figures had risen since data collected on August 5, 2026.
The comparison that worries scientists most is speed. After only 12 weeks since it was declared, Dr Kaseya said, the outbreak had become nearly nine times larger than the West African Ebola outbreak over the same period, in confirmed infections, and six times worse in deaths, making it one of the fastest-growing Ebola epidemics ever recorded.
That trajectory is why researchers are now investigating whether the virus itself has changed. “As Dr Tedros shared with me yesterday (August 5th), it’s time for WHO and Africa to start conducting studies to check if there is an additional issue or maybe if the virus is mutating, because the level of severity of this Bundibugyo outbreak is unprecedented,” Dr Kaseya said, referring to WHO Director-General Dr Tedros Adhanom Ghebreyesus.
No vaccine has been formally approved for Bundibugyo Ebola, and researchers are still racing to generate definitive trial evidence
Against that alarming backdrop sits an unexpected scientific opening. Evidence suggests that Ervebo, the licensed vaccine developed against the Zaire strain of Ebola, may offer some protection against the Bundibugyo strain now driving the DRC outbreak. No vaccine has been formally approved for Bundibugyo Ebola, and researchers are still racing to generate definitive trial evidence.
But Africa CDC has decided that field data already justifies expanding the vaccine’s use among the highest-risk populations rather than waiting.
“Those who were vaccinated with the Zaire strain either develop only minor symptoms when infected with Bundibugyo, or, most importantly, they are not dying. We saw zero deaths among people who were vaccinated. All deaths that we have today are among those who were not vaccinated. It means there is a level of protection,” Dr Kaseya said.
Researchers stressed that the vaccine’s safety is already well established; the open question is how much protection it gives against this particular strain. Ervebo is licensed by the United States Food and Drug Administration (FDA) and the European Medicines Agency, and it is prequalified by WHO.
More than 500,000 doses sit in the global stockpile, and Gavi, the Vaccine Alliance, has committed US$40 million (Ksh5.2 billion) to fund rapid deployment if the vaccine is recommended for this outbreak. Clinical trials are running in parallel to settle the cross-protection question.
Professor Placide Mbala, Africa CDC’s Director for Clinical Trials and Science, said treatment trials already underway in Bunia and Nizi have recruited 68 participants, with preliminary findings expected once the first 100 participants complete 28 days of follow-up.
The trials will also assess new vaccine candidates designed specifically for Bundibugyo Ebola. Smaller cohort studies examining cross-reactivity could begin within two weeks, Africa CDC said, with larger studies to follow shortly after.
Contact tracing is losing effectiveness because more than 70 per cent of newly detected infections now emerge directly from communities
Treatment options are widening too. Africa CDC announced that Remdesivir, an antiviral, will be expanded under compassionate use protocols following encouraging results in Uganda’s outbreak. Dr Kaseya attributed Uganda’s comparatively low fatality rate largely to the drug.
“If the case fatality rate in Uganda is 10 per cent, it is mostly because they used Remdesivir to all people who were sick and those who had contact,” he said.
Unusually for an Ebola emergency, funding is not the constraint. The United States has pledged a further US$242 million (Ksh31.3 billion), pushing total Ebola response funding to roughly US$700 million (Ksh90.6 billion). Humanitarian funding, coordinated through the United Nations Office for the Coordination of Humanitarian Affairs, has exceeded US$1 billion (Ksh129.4 billion). Algeria has released a first US$2 million (Ksh259 million) tranche to Africa CDC, and several other African governments have pledged further support.
What is missing, Dr Kaseya argued, is trust. “Money is not an issue today. The issue is we are not listening. We are not listening to communities. We are thinking that after 17 Ebola outbreaks, we know everything,” he lamented.
The remark followed joint visits to Uganda and DRC with Dr Tedros, during which community representatives repeatedly told the delegation, “We are not involved and we want to be involved.”
That feedback is reshaping the response. Contact tracing, the traditional backbone of outbreak control, is losing effectiveness because more than 70 per cent of newly detected infections now emerge directly from communities rather than from known contacts.
Africa CDC is replacing it with a “village-centred response”, under which every one of Ituri Province’s more than 6,500 villages will nominate trusted local leaders to handle health education, safe burials, testing encouragement and support for residents entering isolation. The plan also brings free healthcare services, paid health workers, reopened schools with added infection controls, and tighter cross-border coordination with Uganda, South Sudan and the Central African Republic.
Africa CDC has expanded diagnostic laboratories from one to 19, cutting test turnaround from several days to about 24 hours
Technology is reinforcing that community layer. Africa CDC plans to equip community health workers with mobile phones and extend internet connectivity to remote villages using Starlink satellite services, letting workers transmit surveillance data in real time from areas that previously had no communications infrastructure.
Dr Kaseya was careful to separate connectivity from data control. “Starlink is only providing connectivity. Africa CDC, supported by PATH, is working on DHIS2. That is the main tool we are using to capture all information under the control of Africa CDC. Starlink is not collecting information,” he explained.
Laboratory capacity has scaled up just as sharply. Africa CDC has expanded diagnostic laboratories from one to 19, cutting test turnaround from several days to about 24 hours, with capacity now exceeding 3,000 tests daily. Sequencing laboratories in Bunia are generating the genomic data scientists need to track viral evolution and confirm, or rule out, the mutation they suspect.
Africa CDC insists the response should leave behind permanent capacity, not temporary fixes, prioritising surveillance systems, laboratory networks, vaccine research, therapeutics, diagnostics, workforce development and sustainable financing long after this outbreak ends. Dr Kaseya also urged governments worldwide to drop unnecessary travel restrictions on affected countries.
“We are saying no travel restrictions when there is an outbreak,” he said, arguing that transparency about outbreaks should be rewarded, not punished, since punitive measures discourage rapid reporting.
For Uganda, South Sudan and the Central African Republic, the countries named in Africa CDC’s cross-border coordination plans, that combination of open borders, expanded vaccination and community leadership is the clearest defence against the virus crossing yet another frontier. Dr Kaseya’s own framing suggests the deeper fix lies beyond laboratories and hospitals altogether. Success, he believes, depends on rebuilding trust and handing power back to the villages living closest to the virus.
