WHO declares Ebola global emergency as death toll hits 87. Is there a vaccine? What we know

The World Health Organization has declared the Ebola outbreak spreading across the Democratic Republic of Congo and Uganda a public health emergency of international concern, its highest level of alarm, after confirming the virus has reached two African capitals and warning that a rare strain for which no approved vaccine or treatment exists may already be circulating far more widely than official figures suggest.

The Global emergency declaration by WHO, issued on Sunday, marks the first such since mpox received the same designation in 2024. It places the Ebola crisis in the same category of international alarm as Covid-19 and other events that have demanded coordinated global responses, unlocking emergency funding and accelerating international coordination.

Why This Ebola Outbreak Is Unlike Previous Ones

The current Ebola outbreak is caused by Bundibugyo ebolavirus, one of the rarest Ebola strains known to infect humans. It has triggered only two documented outbreaks in recorded history, one in Uganda in 2007 and another in eastern Congo in 2012. Taken together, those two previous events produced fewer total cases than the current epidemic has already generated, making this the largest Bundibugyo outbreak ever recorded.

The WHO said the outbreak met the threshold for its highest level of alarm due to cross-border transmission, unexplained clusters of deaths, and profound uncertainty about the true scale of the epidemic. The agency warned that the outbreak may have been circulating undetected for weeks before it was formally identified, with initial testing finding eight positive Ebola samples among just 13 specimens collected from different areas.

"This event is considered extraordinary," WHO Director-General Tedros Adhanom Ghebreyesus said in the declaration, citing the absence of approved Bundibugyo-specific vaccines or therapeutics, ongoing insecurity in eastern Congo and evidence suggesting the outbreak may be significantly larger than official case counts indicate.

Ebola Has Now Reached Kampala and Kinshasa. What the Numbers Show

The geographic reach of the Ebola outbreak has expanded well beyond the remote mining regions where it was first identified. As of 16 May, Congo had reported eight laboratory-confirmed cases, 336 suspected infections, and 87 suspected deaths in Ituri province, according to the Africa Centres for Disease Control and Prevention.

Uganda has confirmed two cases in Kampala, including one fatality, among travellers arriving from Congo. The confirmation of cases in Kinshasa, Congo's capital and home to approximately 20 million people, represents a significant escalation. An outbreak taking hold in a densely populated urban centre of that scale presents containment challenges of an entirely different order from those posed by a remote provincial cluster.

At least four healthcare workers have died in circumstances consistent with viral haemorrhagic fever, raising serious concerns about transmission occurring inside the very clinics and hospitals treating patients.

Is There a Vaccine for This Rare Strain of Ebola?

The short answer is no, and that absence is central to the WHO's alarm. The vaccines and antibody treatments that exist for Ebola were developed almost entirely in response to the Zaire strain, which caused the catastrophic West African epidemic roughly a decade ago that killed more than 11,000 people. That outbreak drove an unprecedented mobilisation of scientific resources and eventually produced approved medical countermeasures.

Bundibugyo ebolavirus, being far rarer, never received comparable attention or investment.

"Ebola Zaire is the one that got all the attention, for very good reasons," said Susan McLellan, director of the biocontainment care unit at the University of Texas Medical Branch.

The WHO has called for urgent clinical trials of experimental vaccines and therapeutics. Candidate vaccines from Oxford University and Moderna are currently under review, but none have yet received approval for use against Bundibugyo infections.

Is There an Approved Treatment for the Congo and Uganda Ebola Strain?

There is currently no approved treatment specifically for Bundibugyo ebolavirus. Health officials are actively considering several potential therapeutic options, including monoclonal antibodies and Gilead Sciences' antiviral drug remdesivir, which gained wider recognition during the Covid-19 pandemic. However, none of these have been approved for use against this particular strain, and their efficacy against Bundibugyo remains unestablished.

The WHO has urged that clinical trials be initiated as rapidly as possible, but the timeline for producing and approving any new treatment is measured in months at minimum, leaving healthcare workers and affected communities without a validated medical toolkit for the foreseeable future.

Why Containing This Ebola Outbreak Is So Difficult

The outbreak is centred in Ituri province in eastern Congo, near the Ugandan border, and specifically around the gold-mining town of Mongbwalu, where workers routinely move between remote camps and regional trading centres. That pattern of mobility has created multiple pathways for transmission that are difficult to monitor or interrupt.

The WHO noted that the urban and semi-urban character of some transmission hotspots has heightened the risk of broader spread of Ebola virus, drawing explicit comparisons to Congo's major Ebola epidemic in North Kivu and Ituri between 2018 and 2019. Eastern Congo's persistent insecurity, significant population displacement, and the logistical complexity of operating in active conflict zones further complicate any containment effort.

The WHO said it was not recommending that any country close its borders or impose travel or trade restrictions, arguing that such measures are ineffective and risk pushing movement through unmonitored crossings where surveillance is impossible.

The Shadow of US Aid Cuts Over the Global Response

The declaration arrives against a backdrop of growing concern among global health experts about the weakening of international disease surveillance infrastructure. Cuts to US foreign aid and disease monitoring programmes have prompted warnings that outbreak response capacity in precisely the regions most vulnerable to Ebola has been materially reduced at the worst possible moment

Congo has confronted more than a dozen Ebola outbreaks across the past half century and is widely regarded as one of the most experienced countries in the world at managing the disease. But that institutional knowledge has repeatedly been tested by the realities of conflict, inadequate infrastructure, and deep-seated distrust of authorities in the country's east, factors that have complicated every previous response and that remain fully present in this one.