Major Outbreaks Timeline
Key Ebola outbreaks from first discovery to the present active outbreak.
- 1976
First Identified Outbreaks — Sudan & DRC
Two simultaneous outbreaks in 1976: Nzara, Sudan (Sudan ebolavirus — 284 cases, 151 deaths) and Yambuku, DRC near the Ebola River (Zaire ebolavirus — 318 cases, 280 deaths). The virus was named after the Ebola River. Both outbreaks were terminated by contact tracing and isolation.
- 1989
Reston, Virginia — Ebola Reston in Non-Human Primates
Ebola Reston virus was discovered in imported crab-eating macaques at a primate research facility in Reston, Virginia. The virus infected several workers but caused no illness in humans, establishing Ebola Reston as non-pathogenic to people. It was the first Ebola virus identified outside Africa.
- 1995
Kikwit, DRC
A major outbreak of Zaire ebolavirus in Kikwit, DRC resulted in 315 cases and 254 deaths (81% case fatality rate). The outbreak highlighted the role of hospital amplification and inadequate infection control in spreading Ebola. International response and barrier nursing techniques brought it under control.
- 2000–2001
Gulu, Uganda — Sudan Ebolavirus
An outbreak of Sudan ebolavirus in Gulu, Uganda resulted in 425 cases and 224 deaths — the largest Sudan ebolavirus outbreak ever recorded. Healthcare facilities were a major amplification site. The outbreak was controlled through community engagement, contact tracing, and healthcare worker training.
- 2007
Bundibugyo, Uganda — New Species
A 2007 outbreak in Bundibugyo District, Uganda led to the discovery of a new species: Bundibugyo ebolavirus (BDBV). The outbreak caused 149 cases and 37 deaths — a notably lower case fatality rate (~25%) compared to Zaire ebolavirus.
- 2014–2016
West Africa Epidemic — Largest in History
The deadliest Ebola outbreak in history spread across Guinea, Liberia, and Sierra Leone, with isolated cases reaching Nigeria, Mali, Senegal, the U.S., UK, Spain, and Italy. Final toll: approximately 28,616 cases and 11,310 deaths. The outbreak devastated healthcare systems, orphaned thousands of children, and triggered the accelerated development of the Ervebo vaccine and the PALM trial antivirals.[1]
- 2018–2020
DRC — North Kivu & Ituri (Second Largest Ever)
The second-largest Ebola outbreak in history: 3,481 cases and 2,299 deaths in eastern DRC. The response was severely complicated by active armed conflict and community mistrust. The Ervebo vaccine was deployed for the first time in an active outbreak setting and is credited with preventing a far larger epidemic.
- 2021
DRC — Guinea Resurgence
A small resurgence of Zaire ebolavirus occurred simultaneously in DRC (12 cases) and Guinea (23 cases, 12 deaths) — Guinea's first outbreak since 2016. Both were rapidly contained. Genetic analysis confirmed the Guinea outbreak was caused by a persisting lineage from the 2014–16 epidemic, demonstrating that the virus can re-emerge from persistent infections in survivors.
- 2022–2023
Uganda — Sudan Ebolavirus
An outbreak of Sudan ebolavirus in Uganda (164 confirmed cases, 77 deaths) was particularly alarming because no licensed vaccine existed for Sudan ebolavirus — Ervebo only protects against Zaire ebolavirus. Experimental Sudan vaccines were deployed under compassionate use. The outbreak was declared over January 11, 2023.
- 2026
DRC — Ituri Province (Novel Variant) Active
Declared May 15, 2026 in Ituri Province, DRC. The outbreak involves a novel Ebola variant that does not match any previously known strain, meaning existing vaccines and antivirals have unconfirmed efficacy. A WHO Public Health Emergency of International Concern (PHEIC) was declared May 17, 2026. See full outbreak details →
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Books About These Outbreaks
First-hand accounts and authoritative histories of the outbreaks documented above — from the 1989 Reston incident through the catastrophic West Africa epidemic.
Disclosure: As an Amazon Associate, EbolaQuestions.com earns from qualifying purchases.
The Hot Zone — Richard Preston (1994)
The definitive account of the 1989 Ebola Reston incident — a near-miss outbreak in a suburban Virginia primate facility, one of the earliest entries in this timeline. Preston's meticulous reporting reads like a thriller but is based entirely on real events. The book that introduced most readers to the reality of hemorrhagic fever outbreaks.
Shop on Amazon →Crisis in the Red Zone — Richard Preston (2019)
Preston's follow-up covers the 2014–16 West Africa epidemic — the most devastating event in this timeline — and follows the doctors, nurses, and scientists who fought it. Written after extensive access to key responders. Essential reading for understanding why the largest outbreak in history happened and how it was eventually stopped.
Shop on Amazon →Spillover — David Quammen (2012)
Quammen's masterwork traces the bat reservoir hypothesis and the ecology of spillover events that trigger every entry in this timeline. Written before the 2014 epidemic, its warnings about why Ebola keeps emerging proved prophetic — and remain directly relevant to the novel 2026 DRC variant.
Shop on Amazon →Frequently Asked Questions
When was Ebola first discovered?
Ebola was first identified in 1976 during two simultaneous outbreaks: one near the Ebola River in Yambuku, DRC (Zaire ebolavirus, 318 cases, 280 deaths) and one in Nzara, Sudan (Sudan ebolavirus, 284 cases, 151 deaths). The virus was named after the Ebola River in DRC.
What was the largest Ebola outbreak?
The 2014–16 West Africa epidemic was the largest in history: approximately 28,616 cases and 11,310 deaths across Guinea, Liberia, and Sierra Leone. It was the first outbreak to spread to multiple countries on different continents simultaneously.
Why do most Ebola outbreaks occur in DRC?
The Democratic Republic of Congo has experienced more Ebola outbreaks than any other country for several reasons: the presence of the natural animal reservoir (fruit bats) in dense equatorial forest; cultural practices involving bushmeat; weak healthcare infrastructure; and in eastern DRC, ongoing armed conflict that disrupts outbreak response. The DRC also has some of the world's best tropical disease surveillance and response capacity, partly because of this history — meaning outbreaks there may be detected sooner than in other settings.
