Information about incidents and outbreaks of Ebola and Marburg, both viral haemorrhagic fevers (VHF), including maps.
Recent incidents and outbreaks
On 1 April 2016, WHO reported a new case of Ebola virus disease in Liberia, thought to have been acquired in Guinea.
On 18 March 2016, WHO reported a new cluster of Ebola cases in Guinea.
On 17 March 2016, Sierra Leone was again declared to be free of Ebola virus transmission, following a successful response to two confirmed cases in January 2016.
On 14 January 2016, WHO declared the end of the most recent outbreak of Ebola virus disease in Liberia. This was the first time during the longstanding West Africa outbreak that all known chains of transmission were stopped, however it was recognised that further flare-ups were to be expected. Robust surveillance and response systems remain vitally important in all three previously affected countries.
On 29 December 2015, WHO declared the end of Ebola virus transmission in the Republic of Guinea. The country entered a 90-day period of heightened surveillance.
On 7 November 2015, WHO declared that Sierra Leone was free from Ebola virus transmission. The country entered a 90 day period of enhanced surveillance.
The West Africa outbreak 2014 to 2016
On 23 March 2014, WHO confirmed an outbreak of Ebola virus disease in southeastern Guinea. This was the first time an outbreak had been diagnosed in this part of Africa, and the index case was traced back to December 2013.
The outbreak spread to neighbouring and nearby countries, particularly Liberia and Sierra Leone, and became the largest ever known outbreak of this disease.
This was the first country affected in the West Africa outbreak and much of the country was affected. During 2015, transmission occurred in gradually contracting geographical areas, and by 23 December 2015 no cases had been confirmed for 7 weeks. On 29 December 2015, WHO declared Guinea free of Ebola virus transmission. A new cluster of cases was reported in March 2016.
Cases of Ebola virus disease were first confirmed in northern Liberia on 30 March 2014 and extensive local transmission followed. All areas of the country reported cases, but case incidence dramatically declined in 2015 and Liberia was declared free of EVD on 9 May 2015. A second outbreak occurred at the end of June 2015 after the country had been free from cases for thirteen weeks. This resulted in a cluster of 6 cases. Liberia was declared free of Ebola virus transmission for the second time on 3 September 2015. A third cluster of 3 cases was reported in November 2015. Transmission associated with this cluster was declared over on 14 January 2016. New cases, likely acquired in Guinea, were reported in April 2016.
On 26 May 2014, the first case in Sierra Leone was confirmed. Every district in the country was subsequently affected. However, during 2015 areas of transmission gradually contracted and weekly case numbers declined to zero. Sierra Leone was declared free of Ebola virus transmission on 7 November 2015 but two cases were reported in January 2016.
Linked Ebola outbreaks and cases in other countries (2014 to 2015)
Mali: two importations leading to a total of 8 cases
Nigeria: 20 cases in Lagos and Port Harcourt, following an initial importation from Liberia
Senegal: a single case imported from Guinea
Italy: one case in a returning healthcare worker
Spain: one case in a healthcare worker involved in the care of patients repatriated from West Africa
United Kingdom: a case was imported into Scotland in December 2014. This was the first Ebola case to be detected in the UK. The patient was a healthcare worker who had been working in an Ebola treatment centre in Sierra Leone
United States: a single EVD case imported from Liberia into Texas in September 2014. Transmission to two healthcare workers subsequently occurred. A further case of EVD was confirmed in a humanitarian aid worker who returned from Guinea in October 2014
Uganda 2014 (Marburg)
On 5 October 2014, the Ministry of Health in Uganda reported that a case of Marburg virus disease had been confirmed in Kampala. No further cases were confirmed, and WHO declared the country free of Marburg virus disease on 13 November 2014.
Democratic Republic of Congo 2014 (Ebola)
On 27 August 2014, WHO announced an Ebola outbreak in Equateur Province, north western Democratic Republic of Congo. This was unrelated to the West African outbreak occurring at the same time. A total of 66 cases were reported, and WHO declared the outbreak to be over on 21 November 2014.
Historic map of outbreaks
This map includes all cases and outbreaks of Ebola or Marburg documented to 31 December 2014. Further information on these historical outbreaks is available.