Ebola vs Marburg: The Same Family, the Same Range
Ebola and Marburg are the two filoviruses that cause large human outbreaks, and their headline figures are nearly interchangeable: WHO puts the average fatality of each at "around 50%", ranging 25–90% for Ebola and 24–88% for Marburg. Neither has ever been established in the United States. The comparison worth making is not the fatality rate — it is what exists to change it.
How to read this page. The tables are the network's two data records side by side — nothing is re-typed, so a figure here is exactly the figure on each virus's own page, with the same source, tier and date. A fatality rate is only comparable when its denominator is the same, and it usually is not; each cell carries its denominator note, and the prose below says which comparisons hold and which do not. An empty cell is a stated absence of measurement, not a low number.
The Figures, Side by Side
Ebola virus disease
A rare but often deadly viral hemorrhagic fever spread through contact with the body fluids of infected people or animals; outbreaks occur mainly in Central and West Africa.
Not Present in the US Not present in the US — the only US cases ever (2014) were travel-associated, and risk to the US public is very low.
Evolving situation: Active WHO-declared PHEIC outbreak (Bundibugyo virus) in DRC, 7,200 confirmed cases and 3,475 confirmed deaths as of September 12, 2026 (CDC page dated September 14; Uganda's linked outbreak is over); zero cases reported in the US, CDC risk to the general US public assessed as low (updated September 8, 2026).
Marburg virus disease
A rare and severe viral hemorrhagic fever related to Ebola, spread through contact with infected body fluids; outbreaks are sporadic and often highly fatal.
Not Present in the US Not present in the US — no domestically acquired cases have ever been recorded; outbreaks occur abroad.
Global, side by side
| Metric | Ebola virus disease | Marburg virus disease |
|---|---|---|
| Annual Exposure / Cases | Data not available | Data not available |
| Severe Outcome Rate | Data not available | Data not available |
| Hospitalization Rate | Data not available | Data not available |
| Case Fatality Rate | 25–90% WHO — Ebola virus disease fact sheet primary source as of 2025-04-24 Of Ebola cases; WHO average ~50%, ranging 25–90% across outbreaks. | 24–88% WHO — Marburg virus disease fact sheet primary source as of 2025-01-20 Of Marburg cases; WHO average ~50%, ranging 24–88% across outbreaks. |
| Annual Deaths | Data not available | Data not available |
Ebola virus disease — global note: WHO puts the average Ebola case fatality rate at about 50%, ranging 25–90% across past outbreaks. Ebola cases and deaths are outbreak-driven rather than an annual global figure, so they are left UNAVAILABLE. Fact sheet re-read 2026-09-15: dated 24 April 2025 (the date now carried here) and unchanged — still "around 50%", 25–90% across outbreaks; the current Bundibugyo outbreak's crude figure is on the US-scope record.
Marburg virus disease — global note: WHO puts the average Marburg case fatality rate at about 50%, ranging 24–88% across past outbreaks. Cases and deaths are outbreak-driven rather than an annual global figure, so they are left UNAVAILABLE. Fact sheet re-read 2026-09-15: dated 20 January 2025 (the date now carried here) and unchanged — still "around 50%", 24–88% across outbreaks; it records Rwanda's first outbreak (September 2024) and Tanzania's (January 2025).
Sources behind every figure above
- CDC — Ebola Outbreak: Current Situation primary source as of 2026-09-12
- WHO — Ebola virus disease fact sheet primary source as of 2025-04-24
- CDC — Marburg Outbreak in Ethiopia: Current Situation primary source as of 2026-01-29
- WHO — Marburg virus disease fact sheet primary source as of 2025-01-20
What the Comparison Shows
The US table is empty for both, and that is the finding. Both records carry the "not present" badge: Ebola's only US cases were the 2014 travel-associated infections (what those cost to treat is on the Ebola spoke); Marburg has never had a domestically acquired US case. Every US funnel cell is unavailable for the honest reason that there is no US series to report, and the fatality ranges appear on the global side, where they belong.
The fatality ranges are outbreak ranges, not rates. "25–90%" and "24–88%" are the spread across past outbreaks, and the records say so: the cases and deaths that produced them are outbreak-driven, so there is no annual global figure to divide. Which end of the range an outbreak lands on depends on the species (the Ebola record notes Bundibugyo virus's two prior outbreaks at about 30% and 50–55% against Ebola virus's up-to-90%), on how many cases go unrecorded, and on care. The 2026 DRC Bundibugyo outbreak — 7,200 confirmed cases and 3,475 deaths as of September 12, 2026, per the record's evolving-situation note — is running at a crude 48%, inside both ranges and above its own species' history.
Where the two actually differ. For Ebola virus (the Zaire species) there is a licensed vaccine, Ervebo, and two licensed antibody treatments, Inmazeb and Ebanga — all species-specific, and none licensed for Bundibugyo virus or for Sudan virus, as the Ebola spoke's treatment page and species comparison set out. Marburg has no licensed vaccine or treatment at all; its outbreaks — most recently Rwanda's first in September 2024 and Tanzania's in January 2025, per the record's WHO fact-sheet note — are managed with supportive care and containment alone. Two viruses with the same fatality range therefore present very different questions: for Ebola, "which species?"; for Marburg, "how fast can it be contained?".
Scale. Ebola's outbreaks have been far larger: 28,600 cases in West Africa in 2013–16 and more than 7,000 in DRC in 2026, against Marburg's largest — 252 cases in Angola in 2004–05 and 153 in DRC in 1998–2000, per the chronology (Languon & Quaye 2019) on the Ebola spoke's outbreak history page. That difference is about ecology and chance, not lethality.
Frequently Asked Questions
Which is deadlier, Ebola or Marburg?
On WHO's figures they are indistinguishable: an average of around 50% for each, ranging 25–90% (Ebola) and 24–88% (Marburg) across past outbreaks. The range reflects species, care and how many mild cases go unrecorded, not a fixed property of either virus.
Has either occurred in the United States?
Ebola: only the 2014 travel-associated cases. Marburg: never a domestically acquired case. Both records carry the "not present" badge and empty US tables for that reason.
What is the practical difference?
Countermeasures. Ebola virus (Zaire species) has a licensed vaccine and two licensed antibody treatments; Marburg has none. Neither Ebola product is licensed for the Bundibugyo species behind the 2026 outbreak.
Why is the 2026 outbreak's fatality above its species' history?
The record notes Bundibugyo virus's two earlier outbreaks at about 30% and 50–55% and the 2026 crude figure at 48%. Whether that reflects the virus, the conflict setting or how cases are counted is not yet established; the Ebola spoke sets out the candidate explanations.
This comparison is statistical and epidemiological. It is not medical advice or a risk assessment for any individual; the network's spoke pages cover symptoms, treatment and what to do about exposure for each virus.