BUNIA – The World Health Organization has declared a public health emergency of international concern following a rapid and deadly outbreak of the Bundibugyo virus, a rare strain of Ebola, across eastern Democratic Republic of Congo (DRC) and into neighboring Uganda.
WHO Director-General Tedros Adhanom Ghebreyesus expressed deep concern over the “scale and speed” of the epidemic, citing a sharp increase in suspected deaths-now totaling at least 134-and more than 500 suspected cases. The emergence of the virus in densely populated urban areas, the infection of healthcare workers, and significant population movement have accelerated the crisis, pushing the international community into a race against a pathogen for which there are currently no approved medicines or vaccines.
The outbreak underscores the precarious nature of global health surveillance in conflict-prone regions. The Bundibugyo virus is one of several species within the Ebolavirus genus, distinct from the more common Zaire and Sudan strains. Because diagnostic tests are often tailored to the Zaire strain-the most frequent cause of major outbreaks-the current crisis spread undetected for weeks. Early data from previous episodes suggest the Bundibugyo strain can kill up to 40 percent of infected patients, making it less lethal but harder to track than Zaire Ebola, which has been the focus of most testing and vaccine development.[1]
Diagnostic failures and infrastructure collapse
The escalation of the outbreak is being attributed to a critical failure in the early detection chain, exposing weaknesses in both national systems and international support. Congo authorities reported that the first death occurred on April 24 in Bunia, after which the body was repatriated to the Mongbwalu health zone, a high-population mining area where traditional burial practices often involve close physical contact.
“That caused the Ebola outbreak to escalate,” said Congo’s health minister, Samuel Roger Kamba, referring to the movement of the body and subsequent chain of exposure.
When a second patient fell ill on April 26, samples were dispatched to the capital, Kinshasa, for analysis. The journey spans more than 1,000 kilometers across some of the world’s most degraded infrastructure, illustrating how distance and insecurity can blunt even well-intentioned response plans. Initial tests focused on the Zaire strain and returned negative results, leading to a lethal delay in containment efforts as local health teams treated the cluster as an unexplained febrile illness rather than Ebola.
Dr. Richard Kitenge, the health ministry incident manager for Ebola, confirmed that the negative results for the common strain masked the presence of the Bundibugyo virus. It was not until May 14 that the first official confirmation of the rare strain was made, by which time the WHO had been alerted to approximately 50 deaths in Mongbwalu, including four health workers.
“Our surveillance system didn’t work,” said Jean-Jaques Muyembe, a virologist at the National Institute of Bio-Medical Research. “The Bunia laboratory … should have continued searching and sent the samples to the national laboratory. Something went wrong there. That’s why we ended up in this catastrophic situation.”
Under the legally binding International Health Regulations (2005), countries must rapidly detect, verify, and report events that may constitute a public health emergency of international concern. The misdiagnosis and delayed confirmation in eastern DRC will likely become a test case of how those obligations are implemented in fragile states where laboratories are under-resourced and health workers operate under the threat of violence.
Geopolitical volatility in the epicentre
The medical crisis is compounding a volatile security situation in the eastern DRC, where overlapping conflicts already constrain state authority. Cases have been confirmed in several major localities, including:
- Bunia: The capital of Ituri province and the site of the first known death, as well as a hub for internally displaced people fleeing nearby fighting.
- Goma: The capital of North Kivu, currently under the control of the Rwanda-backed M23 rebel group and a key commercial and transport gateway to Rwanda and beyond.
- Mongbwalu, Nyakunde, and Butembo: High-density areas home to over a million people, with informal mining camps and frequent cross-border movement.
The involvement of the M23 rebels has added a layer of diplomatic and operational complexity to the response. Benjamin Mbonimpa, M23’s permanent secretary, stated that the rebel government has established entry and exit points in Goma and intends to manage funeral services to prevent further spread. “Our priority is to protect the population within our jurisdiction, and we urge people to resume their daily activities,” Mbonimpa said.
For Kinshasa and its partners, that assertion of authority creates an immediate dilemma: international agencies must negotiate access with an armed group that the national government accuses of undermining its sovereignty, even as disease control depends on coherent messaging and trust across front lines.
The lack of laboratory capacity further hampers the response; only facilities in Kinshasa and Goma have the ability to test for the Bundibugyo strain, the latter of which is now behind rebel lines. Health officials warn that samples are taking days to reach functioning labs, slowing isolation and contact-tracing decisions that are typically made within hours during better-resourced outbreaks.
The race for a vaccine
The current outbreak presents a unique clinical and regulatory challenge because the vaccines used in previous DRC epidemics, such as Ervebo, target different Ebola species. Dr. Anne Ancia, head of the WHO team in Congo, noted that while Ervebo is being considered for possible use as a precautionary tool, any approved deployment would take two months to materialize once logistics, ethics approvals, and cold-chain arrangements are in place.
“I don’t see that in two months we will be done with this outbreak,” Ancia said, warning governments that response funding must be planned on a medium-term horizon rather than as a short, one-off emergency.
Congo is currently awaiting shipments from the United States and Britain of ChAdOx1, an experimental vaccine developed by researchers at Oxford. While designed for the Zaire and Sudan types, virologists are hoping to assess its efficacy in the field against Bundibugyo, which has historically seen little commercial interest because of its rarity.[2] “We will administer the vaccine and see who develops the disease,” Muyembe said, acknowledging that what unfolds in eastern Congo could help determine future investment in broadly protective Ebola shots.
The international response has faced criticism over funding and presence. Matthew M Kavanagh, director of the Georgetown University Center for Global Health Policy and Politics, linked the surveillance failure to previous U.S. decisions to withdraw from the WHO and cut foreign aid, describing these as “the exact surveillance system meant to catch these viruses early.” Public health experts say those earlier choices have left key regional laboratories and community surveillance networks overly dependent on short-term project grants that are difficult to sustain between crises.
In response, the US State Department has announced an immediate allocation of US$13 million (NZ$22.2 million) for the emergency response. Congolese officials, however, stress that success will depend not only on emergency cash but also on how quickly funds translate into trained staff, laboratory reagents, protective equipment, and the security guarantees needed to move safely through contested territory.
Human toll and community panic
In Bunia, the psychological impact of the virus has triggered widespread anxiety among residents who remember the devastation of previous Ebola outbreaks. Rumours of hidden cases and fears that authorities are undercounting deaths are circulating in markets and displacement camps, complicating efforts to promote isolation and safe burials. Noëla Lumo, a resident who previously lived in Beni during a former epidemic, has begun hand-making protective masks for her community.
“I know the consequences of Ebola, I know what it’s like,” Lumo said.
The virus is highly contagious, transmitted through bodily fluids such as blood, vomit, and semen. It manifests through fever, muscle pain, unexplained bruising, and severe gastrointestinal distress. Dr. Craig Spencer, an associate professor at the Brown University School of Public Health and a survivor of a previous Ebola outbreak in Guinea, highlighted the specific risk to caregivers.
“Ebola is very much a disease of compassion in that it impacts the people who are more likely to be taking care of sick folks,” Spencer said, adding that family members and health workers are often the first to fall ill when protective gear is scarce or when communities distrust official treatment centres.
As of the latest reports, 30 cases are confirmed in Congo, while Uganda has confirmed two cases-including one death in Kampala-linked to travelers from the DRC. The confirmation of cross-border transmission has prompted Ugandan authorities to step up screening at land crossings and airports, even as trade and daily commuting between the two countries continues.
While the US Centers for Disease Control and Prevention and the Africa CDC are not yet on the ground, Doctors Without Borders and the Red Cross have begun operations in the affected provinces, supporting isolation wards, infection-prevention training and safe-burial teams. Local civil society leaders are urging authorities to integrate these emergency measures with longer-term investments in primary healthcare, arguing that the same clinics and community workers needed to fight Ebola must also manage malaria, cholera and routine vaccination campaigns once the cameras leave.
The World Health Organization continues to maintain the outbreak as a public health emergency of international concern, with teams working to identify “patient zero” and break the transmission chain. For Congo and its neighbours, the coming weeks will test not only the science of rare-strain Ebola, but also whether fragile health and security systems can uphold global rules designed to keep local outbreaks from becoming the world’s next pandemic scare.
