Key dates in the latest Ebola epidemic, the worst ever outbreak of the haemorrhagic fever which first surfaced in 1976 in what is now the Democratic Republic of Congo.

According to the latest toll given by the World Health Organization (WHO), the epidemic has left 11,300 dead, mainly in the west African states of Guinea, Liberia and Sierra Leone, out of almost 29,000 cases.

But the WHO's declaration that Sierra Leone had ended the outbreak raised hopes that the virus can be defeated.

- Epidemic starts in Guinea -

- December 6, 2013: A two-year-old child dies in southern Guinea and is later identified as "patient zero". The virus remains localised until February 2014, when a careworker in a neighbouring province dies.

- March 24, 2014: Authorities in Guinea and the WHO say that since January the country has recorded 87 suspected cases of viral haemorrhagic fever, including 61 deaths. Scientists studying samples in the French city of Lyon confirm it is Ebola.

- Ebola begins to spread -

- May 26, 2014: Sierra Leone confirms its first case, to be followed in late July by Nigeria, in August by Senegal and in October by Mali. Senegal and Nigeria are declared free of Ebola in October, while Mali is declared Ebola free in January 2015.

- May 30, 2014: Ebola is "out of control", according to the aid group Doctors Without Borders (MSF). The three worst-hit countries, Guinea, Sierra Leone and Liberia, declare measures including states of emergency and quarantines. Many neighbouring nations close their borders with the affected countries.

- Ebola declared a "public health emergency" -

- On August 8, 2014, The WHO declares Ebola a "public health emergency of international concern".

Four days later it authorises the use of experimental drugs to fight Ebola after an ethical debate.

That day, a Spanish missionary infected in Liberia dies in Madrid, the first European fatality.

- Death in the US -

- A Liberian is hospitalised in the US state of Texas on September 30, the first Ebola infection diagnosed outside Africa, and dies on October 8.

Two days earlier, a Spanish nurse in a Madrid hospital becomes the first person to be infected outside Africa. She is treated and given the all-clear on the 19th.

- Ebola begins a halting retreat, Liberia declared free of outbreak -

On February 22, 2015, Liberia says it is lifting nationwide curfews and re-opening borders, as the epidemic begins to retreat. In Guinea schools reopen on January 19, while Sierra Leone reopens schools on March 30.

But on February 28, Sierra Leone reintroduces travel restrictions it eased in January as the number of new cases rises.

Liberia is finally declared Ebola-free on May 9, only to see the fever resurface six weeks later.

- Surge in Guinea and Sierra Leone -

The WHO says on May 20 that new cases have spiked higher in Guinea, and in Sierra Leone where officials berate people who flouted quarantine restrictions.

Guinea extends its health emergency on June 6, and on June 12, Sierra Leone reimposes a three-week curfew.

The capital Freetown suffers a fresh outbreak in mid June, and on June 30, Liberia says Ebola has returned there too.

- More money pledged, closing in on an effective vaccine -

- International donors pledge $3.4 billion in new funds on July 10 to help Ebola-hit countries stamp it out.

- The WHO says on July 31 that an Ebola vaccine provided 100-percent protection in a field trial in Guinea, suggesting that the world is "on the verge of an effective Ebola vaccine."

- Liberia ends second outbreak -

- The WHO says on September 3 that Liberia has beaten its second outbreak, after discharging its last four Ebola patients and managing to go 42 days with no new infections.

- Outbreak declared over in Sierra Leone -

- November 7: Sierra Leone is declared free of the outbreak, six weeks after its last patient was recorded.