6,757 confirmed cases
As of 7 September, WHO reported 3,267 deaths: a crude case-fatality ratio of 48.3%. Cases had reached 61 health zones across six provinces.
One licensed vaccine. One virus species.
Vaccine
for Ebola
Ervebo can be highly effective against Ebola virus disease caused by Zaire ebolavirus. It does not provide established protection against every virus that causes Ebola disease.
Possible exposure or symptoms?Do not arrive unannounced at a clinic. Isolate from others, avoid body-fluid contact and call emergency or public-health services for instructions.
Current context · reviewed 18 September 2026
The active emergency is not vaccine-matched.
WHO reports an ongoing Bundibugyo virus disease outbreak in the Democratic Republic of the Congo. Uganda declared its linked outbreak over in August, but remains at risk of imported cases.
No licensed Bundibugyo vaccine
Ervebo is not licensed for this species. WHO permits its use against Bundibugyo only through carefully designed research protocols while evidence is generated.
Geography is not enough
Risk depends on direct contact with cases, health facilities, funerals, bodies, body fluids and infected wildlife, not simply being in the same country.
Fifty years of outbreaks
Scale depends on biology and the response around it.
Case-fatality ratios are not fixed. Species, early detection, access to fluids and critical care, specific treatment, trust, conflict and whether cases reach treatment centres all change the outcome.
OutbreakVirusReported tollWhat changed
Yambuku, DRC · 1976First recognized EBOV outbreakEbola virus318 cases
280 deaths · 88%Reuse of needles and close hospital and funeral contact amplified transmission.
280 deaths · 88%Reuse of needles and close hospital and funeral contact amplified transmission.
Uganda · 2000–01Large pre-vaccine outbreakSudan virus425 cases
224 deaths · 53%Contact tracing, isolation and safer burials interrupted transmission without a vaccine.
224 deaths · 53%Contact tracing, isolation and safer burials interrupted transmission without a vaccine.
West Africa · 2014–16Guinea, Liberia, Sierra LeoneEbola virus28,652 cases
11,325 deaths · 40%Urban spread, delayed recognition and cross-border movement produced the largest historical epidemic and accelerated vaccine trials.
11,325 deaths · 40%Urban spread, delayed recognition and cross-border movement produced the largest historical epidemic and accelerated vaccine trials.
Eastern DRC · 2018–20Conflict-affected provincesEbola virus3,470 cases
2,287 deaths · 66%Ring vaccination and antibody treatments were available, but insecurity, delayed care and mistrust obstructed control.
2,287 deaths · 66%Ring vaccination and antibody treatments were available, but insecurity, delayed care and mistrust obstructed control.
Uganda · 2022No licensed matched vaccineSudan virus164 cases
55 deaths · 34%Surveillance, isolation, contact follow-up, infection control and safe burials ended the outbreak.
55 deaths · 34%Surveillance, isolation, contact follow-up, infection control and safe burials ended the outbreak.
DRC · 2026 ongoingFigures at 7 SeptemberBundibugyo virus6,757 DRC cases
3,267 deaths · 48.3%Geographic expansion, displacement, insecurity and delayed care continue to sustain transmission.
3,267 deaths · 48.3%Geographic expansion, displacement, insecurity and delayed care continue to sustain transmission.
Selected outbreaks, not a complete chronology. Percentages use reported cases and deaths and may change as records are reconciled.
The licensed option
Ervebo® is precise, fast and not routine.
A live recombinant vesicular stomatitis virus vaccine carrying one Ebola-virus protein. It cannot cause Ebola disease.
rVSV-ZEBOV
One intramuscular dose
- Protects against
- Ebola virus disease caused by Ebola virus, formerly called Zaire ebolavirus.
- Licensed ages
- From 12 months in the US and from 1 year in the EU; outbreak recommendations can include younger infants under public-health protocols.
- Evidence
- The Guinea ring-vaccination trial observed no cases from day 10 among immediately vaccinated eligible contacts, versus cases in delayed rings. Real-world outbreak studies support high effectiveness.
- Duration
- Protection persists, but the exact duration and need for boosters are not fully defined.
Who usually receives it?
Contacts and contacts-of-contacts during a matched Ebola-virus outbreak, frontline and healthcare workers at risk, outbreak responders, and selected laboratory personnel. It is not a standard tourist vaccine.
Common effects
Injection pain, headache, fever, tiredness, muscle or joint pain, nausea and rash are usually short-lived. Arthritis or joint symptoms can occur. Severe allergy is rare.
After vaccination
Continue PPE, hand hygiene and exposure controls. Protection is not immediate, not perfect and not established for Sudan, Bundibugyo or Taï Forest virus disease.
What happened to Zabdeno + Mvabea?
The two-dose regimen was authorised in Europe, with Mvabea given about eight weeks after Zabdeno. The European Commission withdrew both authorisations in May 2026 at the manufacturer’s request for commercial reasons. It was not suited to rapid ring vaccination and human efficacy was inferred largely from immune responses and animal data.
Know the virus, not just the label
Ebola diseases are related, not interchangeable.
Laboratory confirmation identifies the virus and determines whether licensed vaccine and antibody treatments are expected to work.
Ebola virus
Formerly Zaire ebolavirus · EBOVCaused the 2014–2016 West African epidemic and several DRC outbreaks. Ervebo, Inmazeb and Ebanga are directed against this virus.
Sudan virus
SUDVHas caused major outbreaks in Uganda and Sudan. Candidate vaccines have entered outbreak trials, but routine licensed protection is not yet available.
Bundibugyo virus
BDBVPast outbreaks had substantial mortality. Candidate vaccines and treatments are being evaluated; Ervebo cross-protection remains unproven in people.
Taï Forest virus
TAFVOnly one known human case, linked to a chimpanzee necropsy in Côte d’Ivoire. No licensed vaccine.
Reston virus: infection has occurred in non-human primates and pigs. Human infections have not caused recognized disease, but surveillance remains important.
Exposure discussion guide
Would vaccination even apply to me?
This tool does not calculate a percentage or clear anyone for travel. It identifies when public-health or occupational assessment is needed.
Recognition and treatment
Early Ebola can look ordinary.
Malaria, typhoid, meningitis and other viral haemorrhagic fevers can look similar. Bleeding is not required and is often absent early.
Incubation
People do not transmit Ebola before symptoms. Most illness begins with sudden fever, fatigue, headache, sore throat and muscle pain.
Gastrointestinal illness
Vomiting, severe diarrhoea, abdominal pain, rash and kidney or liver dysfunction may follow. Fluid and electrolyte losses can be profound.
Severe disease
Shock, confusion, organ failure and abnormal bleeding can occur. Average fatality across past outbreaks is about 50%, varying roughly 25–90% by outbreak and care.
Treatment works
Early intensive supportive care improves survival. For Ebola virus disease caused by EBOV, WHO recommends the antibodies Inmazeb or Ebanga. These are not proven treatments for every species.
Testing cannot be done casually at home
Diagnosis relies mainly on RT-PCR in specialised systems. Samples are an extreme biohazard and require trained collection, packaging and laboratory handling. A public-health team decides who should be tested and where.
How transmission actually happens
Close contact, not casual proximity.
Ebola spreads through direct contact of broken skin or mucous membranes with infected blood or body fluids, contaminated objects, infected animals, or bodies during unsafe burials.
Before symptomsNot infectious
People do not transmit Ebola during the symptom-free incubation period, which lasts 2–21 days.
Early illnessRisk begins
Virus becomes transmissible when symptoms start. Early fever may look nonspecific, making rapid reporting and isolation important.
Severe illnessHighest practical risk
Viral levels and exposure to vomit, diarrhoea, blood and medical procedures rise. Carers and health workers face the greatest danger without rigorous PPE.
Death or recoverySome risk persists
Bodies remain highly infectious. Survivors are not generally contagious through ordinary contact, but virus can persist in semen and protected body sites.
Can the transmission mode change?
No evidence of casual airborne spread
Viruses mutate, and outbreaks can shift from animal-to-human spillover to sustained person-to-person transmission. That changes the pattern of spread, not the route. Human outbreaks remain driven by direct contact with infectious fluids, contaminated materials and bodies. Tiny droplets or splashes at very close range, and aerosol-generating medical procedures, demand eye, face and respiratory protection; this does not make Ebola behave like measles, influenza or COVID-19.
Ordinary shared air, walking past someone, or being in the same country does not by itself create an exposure.
A person is not contagious during the symptom-free incubation period. Infectiousness rises as illness becomes more severe.
Virus can remain in immune-protected sites after recovery. Transmission through semen has been documented many months later; survivors receive testing and safer-sex guidance.
- 01
Find and isolate cases early
Rapid alerts, safe transport, treatment centres and laboratory confirmation shorten the time an infectious person remains in the community.
- 02
Trace contacts for 21 days
Daily follow-up catches symptoms before onward exposure. Contacts should not travel internationally during monitoring unless medically evacuated.
- 03
Protect care and laboratories
Trained staff, PPE, a buddy system, safe injections, supervised removal, waste control and protected specimen handling stop health-facility amplification.
- 04
Use safe, dignified burials
Trained teams prevent contact with highly infectious bodies while preserving family presence and culturally important practices.
- 05
Vaccinate when species-matched
For EBOV outbreaks, rapid ring vaccination protects contacts and contacts-of-contacts. It complements rather than replaces tracing and treatment.
- 06
Work with communities
Clear information, local leadership, survivor support and respectful care reduce concealment, unsafe care and resistance to response teams.
Risk of global spread
Exported cases are possible. Sustained worldwide spread is less likely.
Incubating travellers can cross borders because they are symptom-free and not yet contagious. Once symptoms begin, modern travel can still export a case, as happened during earlier epidemics and in 2026. Regional land movement, informal crossings, healthcare deployment and delayed detection are greater concerns than casual contact on an aircraft.
Because Ebola requires direct fluid contact, isolation, contact tracing and infection control can stop onward chains. WHO recommends screening, surveillance and cross-border coordination rather than general border closures or blanket travel and trade bans.
Escalation scenarios
What would a “Contagion” event really require?
A worldwide airborne Ebola pandemic is not a credible planning assumption today. A serious multi-country emergency caused by repeated direct-contact transmission is credible and deserves preparation.
Regional acceleration
Conflict, displacement, mining and trade routes move exposed people across Central and East Africa while insecurity blocks tracing. Cases visit several facilities, protective supplies run short, funerals occur before diagnosis and infection spreads among families and health workers.
Multiple linked outbreaks become harder and costlier to contain.Repeated international export
Several travellers depart during incubation or early nonspecific illness. A case reaches a distant city, exposes household or healthcare contacts and triggers intensive monitoring. Several exports at once could strain specialist isolation capacity.
Expensive local clusters do not automatically become global community spread.Urban hospital amplification
Delayed recognition in a dense city combines with crowded emergency departments, unsafe injections, inadequate PPE, poor waste systems and fear-driven avoidance of authorities.
Hospitals amplify transmission until care, trust and tracing are restored.Efficient casual airborne spread
This would require a profound and currently unsupported change in transmission. Mutation alone does not make that leap likely, and no human Ebola outbreak has shown sustained measles-like airborne spread.
Theoretical does not mean probable or useful for present-day advice.International support is prevention at the source, not charity after the fact.
Underfunded surveillance, laboratories, PPE, treatment centres, community partnerships, vaccine research and contact tracing allow more transmission and more opportunities for viral evolution. A future variant would not need to become airborne to do far greater damage: even somewhat earlier shedding, greater environmental stability, more efficient fluid-contact transmission or repeated urban export could overwhelm fragile systems and rebound internationally at vastly greater cost.
Isolation without panic
Target exposure, not nationality.
Cases: immediate specialist isolation and no ordinary travel until clinically recovered and required virus-specific tests are negative.
Symptomatic suspected cases: call ahead, use designated transport and avoid public waiting rooms.
Contacts: active daily monitoring for 21 days, prompt isolation if symptoms begin, and no international travel during monitoring unless medically evacuated.
Protected workers and ordinary travellers: no indiscriminate quarantine merely for visiting a country. Assess the actual exposure, symptoms, place and dates.
Borders: targeted exit screening, shared contact data and prepared referrals are more useful than blanket closures, which can drive movement underground and obstruct aid.
Who makes it, who can get it, what does it cost?
Licensed does not mean retail.
Merck & Co. / MSD
Ervebo is manufactured by Merck Sharp & Dohme, known as MSD outside the United States and Canada. It is a single-dose live recombinant vaccine.
Usually through a programme
It is prescription-only where marketed, but is not a routine walk-in travel vaccine. Most doses are reserved for ring vaccination during matched Zaire Ebola outbreaks and preventive programmes for eligible healthcare, laboratory and frontline workers. A country requests outbreak stock through the WHO-led ICG; an individual cannot order from that stockpile.
US$98.60 procurement price
UNICEF lists a 2026 awarded price of US$98.60 per dose under its multi-year supply agreement. That figure includes a stockpile service component and is not a guaranteed retail price. Consultation, administration, specialist handling and programme costs are separate; a normal consumer cash price is generally unavailable because public retail supply is not established.
Ordinary tourists are not usually offered Ervebo solely because they are visiting an African country. Healthcare, laboratory, burial, outbreak-response or other direct-contact duties require an occupational-health and public-health assessment well before travel.
Related epidemics, different biology
Marburg is a cousin. HIV and COVID are lessons.
Comparisons help only when the differences are kept visible.
Marburg virus disease
Marburg and Ebola are filoviruses. Both can begin with nonspecific fever, progress to severe gastrointestinal illness, shock and bleeding, and spread through direct contact with infectious body fluids and unsafe burials. Egyptian fruit bats are the established natural host for Marburg.
First recognized in 1967 after laboratory workers in Germany and Belgrade were exposed to tissues from imported African green monkeys: 31 cases and seven deaths. Major later outbreaks included DRC in 1998–2000 and Angola in 2004–05, where 374 cases and 329 deaths were reported. More recent outbreaks have occurred in Ghana, Equatorial Guinea, Tanzania and Rwanda.
No licensed Marburg vaccine or specific treatment is available, though candidates are in development.HIV
HIV spreads during long periods when a person may feel well, establishes lifelong infection without treatment and is transmitted mainly through sex, blood and from parent to child. That biology enabled silent global dissemination before recognition.
Ebola differs: acute illness usually becomes obvious, transmission generally begins with symptoms, and survivors usually clear infectious virus from blood. The parallel is that stigma, distrust, inequitable access and delayed international action worsen both epidemics. Persistent Ebola virus in semen also makes respectful survivor follow-up important.
COVID-19
SARS-CoV-2 transmits efficiently through the air, including before symptoms and from people who never feel ill. That combination made border temperature checks and symptom-based isolation insufficient to stop a pandemic.
Ebola does not currently share those features. Its close-contact route makes isolation and tracing far more powerful. The COVID lesson is operational: prepare laboratories, supply chains, trusted communication, surge staffing and international financing before exponential growth.
Evidence library
Authorities, guidance and papers.
Access dates and publication dates matter during a live emergency. These links identify the evidence behind the main claims on this page.
Current outbreak · WHO · 10 Sep 2026Bundibugyo outbreak situation report
Case totals, geography, cross-border risk, control response and current vaccine research.
Vaccine policy · WHO · 31 Aug 2026Ervebo during Bundibugyo outbreaksPossible cross-protection, human evidence gaps and the research-protocol recommendation.
Vaccine overview · WHO · 9 Sep 2026Ebola vaccine questions and answersLicensed species coverage, target groups, ring vaccination and candidate vaccines.
Clinical authority · WHOEbola disease fact sheetSymptoms, incubation, fatality, diagnosis, treatment, transmission and survivor guidance.
Transmission · CDC · 2 Jun 2026How Ebola disease spreadsBody-fluid exposure, contaminated materials, animals and post-recovery sexual transmission.
Regulatory · EMAErvebo product assessmentIndication, immune response, common adverse effects and restrictions.
Peer-reviewed study · NEJMRing vaccination in eastern DRCReal-world evidence supporting rVSV-ZEBOV effectiveness alongside standard controls.
Related filovirus · WHO · 20 Jan 2025Marburg fact sheet and chronologyNatural host, transmission, historical outbreaks, fatality and absence of an approved vaccine.
Case study · WHORwanda Marburg outbreak, 2024A modern urban and healthcare-associated outbreak controlled through rapid coordinated response.
Comparison · WHOHIV and AIDS fact sheetLong asymptomatic transmission, chronic infection, treatment and prevention context.
Editorial review: 18 September 2026. Outbreak figures and recommendations may change; open the live source before making a health, occupational or travel decision.
Primary guidance
Check the live source.
This page will be updated, but outbreak numbers and recommendations can change faster than any general website.