West African Ebola virus epidemic

West African Ebola virus epidemic
2014 ebola virus epidemic in West Africa simplified.svg
Simplified Ebola virus epidemic situation map
DateDecember 2013 – June 2016[1][2]
  • Note: current estimates suggest that between 17 percent and 70 percent of Ebola cases were unreported.[3]
Country Cases Deaths Last update
On 9 June 2016 by WHO
Liberia Liberia 10,666 4,806outbreak ended 9 June 2016[2]
Sierra Leone Sierra Leone 14,122 3,955outbreak ended 17 March 2016[4]
Guinea Guinea 3,804 2,536outbreak ended 1 June 2016[5]
Nigeria Nigeria 20 8outbreak ended 19 October 2014[6]
Mali Mali 8 6outbreak ended 18 January 2015[7]
United States United States 4 1outbreak ended 21 December 2014[8]
Italy Italy 1 0outbreak ended 20 July 2015[9]
United Kingdom United Kingdom 1 0 outbreak ended 10 March 2015[10]
Senegal Senegal 1 0outbreak ended 17 October 2014[6]
Spain Spain 1 0outbreak ended 2 December 2014[11]
Total 28,616 11,310 as of 8 May 2016

The West African Ebola virus epidemic (2013–2016) was the most widespread outbreak of Ebola virus disease (EVD) in history—causing major loss of life and socioeconomic disruption in the region, mainly in the countries of Guinea, Liberia, and Sierra Leone. The first cases were recorded in Guinea in December 2013; later, the disease spread to neighboring Liberia and Sierra Leone,[12] with minor outbreaks occurring elsewhere. It caused significant mortality, with the case fatality rate reported at slightly above 70%,[12][13][14][note 1] while the rate among hospitalized patients was 57–59%.[15] Small outbreaks occurred in Nigeria and Mali,[7][16] and isolated cases were recorded in Senegal,[17] the United Kingdom and Sardinia.[14][18] In addition, imported cases led to secondary infection of medical workers in the United States and Spain but did not spread further.[19][20] The number of cases peaked in October 2014 and then began to decline gradually, following the commitment of substantial international resources. As of 8 May 2016, the World Health Organization (WHO) and respective governments reported a total of 28,616 suspected cases and 11,310 deaths[21] (39.5%), though the WHO believes that this substantially understates the magnitude of the outbreak.[22][23]

On 29 March 2016, the WHO terminated the Public Health Emergency of International Concern status of the outbreak.[24][25][26] Subsequent flare-ups occurred; the last was declared over on 9 June 2016, 42 days after the last case tested negative on 28 April 2016 in Monrovia.[27]

The outbreak left about 17,000 survivors of the disease, many of whom report post-recovery symptoms termed post-Ebola syndrome, often severe enough to require medical care for months or even years. An additional cause for concern is the apparent ability of the virus to "hide" in a recovered survivor's body for an extended period of time and then become active months or years later, either in the same individual or in a sexual partner.[28] In December 2016, the WHO announced that a two-year trial of the rVSV-ZEBOV vaccine appeared to offer protection from the strain of Ebola responsible for the West Africa outbreak. The vaccine has not yet been given regulatory approval, but it is considered to be so effective that 300,000 doses have already been stockpiled.[29][30]


Ebola virus disease (commonly known as "Ebola") was first described in 1976 in two simultaneous outbreaks in the Democratic Republic of the Congo and what is now South Sudan.[31] Ebola had been discovered to be endemic to West Africa decades prior to the 2013–2016 outbreak, but this was not well understood in West Africa or by the international health community.[32][33] The 2013–2016 outbreak was the first anywhere in the world to reach epidemic proportions. Previous outbreaks had been brought under control within a few weeks. Extreme poverty, dysfunctional healthcare systems, distrust of government after years of armed conflict, and the delay in responding for several months, all contributed to the failure to control the epidemic. Other factors included local burial customs of washing the body and the unprecedented spread of Ebola to densely populated cities.[34][35][36][37][38]

Map showing death statistics as of 2014

As the outbreak progressed, many hospitals, short on both staff and supplies, were overwhelmed and closed down, leading some health experts to state that the inability to treat other medical needs may have been causing "an additional death toll [that is] likely to exceed that of the outbreak itself".[39][40] Hospital workers, who worked closely with the highly contagious body fluids of the victims, were especially vulnerable to contracting the virus; in August 2014, the WHO reported that ten percent of the dead had been healthcare workers.[41] In September 2014, it was estimated that the affected countries' capacity for treating Ebola patients was insufficient by the equivalent of 2,122 beds; however, by December 2014 there were enough beds to treat and isolate all reported cases, although the uneven distribution of cases was resulting in serious shortfalls in some areas.[42]

The WHO has been widely criticised for its delay in taking action to address the epidemic.[43] On 8 August 2014, it declared the outbreak a public health emergency of international concern.[44] By September 2014, Médecins Sans Frontières/Doctors Without Borders (MSF), the non-governmental organization with the largest working presence in the affected countries, had grown increasingly critical of the international response. Speaking on 3 September, the International President of MSF spoke out concerning the lack of assistance from United Nations (UN) member countries: "Six months into the worst Ebola epidemic in history, the world is losing the battle to contain it."[45] In a 26 September statement, the WHO stated that "[t]he Ebola epidemic ravaging parts of West Africa is the most severe acute public health emergency seen in modern times" and its Director-General called the outbreak "the largest, most complex and most severe we've ever seen".[46] In March 2015, the United Nations Development Group reported that due to a decrease in trade, closing of borders, flight cancellations, and drop in foreign investment and tourism activity fuelled by stigma, the epidemic had resulted in vast economic consequences in both the affected areas in West Africa and even in other African nations with no cases of Ebola.[47]

On 28 January 2015, the WHO reported that for the first time since the week ending 29 June 2014, there had been fewer than 100 new confirmed cases reported in a week in the three most-affected countries. The response to the epidemic then moved to a second phase, as the focus shifted from slowing transmission to ending the epidemic.[48] On 8 April 2015, the WHO reported a total of only 30 confirmed cases,[49] and the weekly update for 29 July reported only seven new cases.[50] Cases continued to gradually dwindle and on 7 October 2015, all three of the most seriously affected countries recorded their first joint week without any new cases.[51] However, as of late 2015, while the large-scale epidemic had ended, sporadic new cases were still being recorded, frustrating hopes that the epidemic could be declared over.[52]

On 31 July 2015, the WHO announced "an extremely promising development" in the search for an effective vaccine for Ebola virus disease. While the vaccine had shown 100% efficacy in individuals, more conclusive evidence was needed regarding its capacity to protect populations through herd immunity.[53][54] In August 2015, after substantial progress in reducing the scale of the epidemic, the WHO held a meeting to work out a "Comprehensive care plan for Ebola survivors" and identify research needed to optimize clinical care and social well-being. Stating that "the Ebola outbreak has decimated families, health systems, economies, and social structures", the WHO called the aftermath of the epidemic "an emergency within an emergency." Of special concern is recent research that shows some Ebola survivors experience a so-called "post-Ebola Syndrome", with symptoms so severe that survivors may require medical care for months and even years.[55][56] As the main epidemic was coming to an end in December 2015, the UN announced that 22,000 children had been orphaned, losing one or both parents to Ebola.[57] On 29 March 2016, the Director-General of WHO terminated the Public Health Emergency of International Concern status of the West African Ebola virus epidemic.[24]

Other Languages
oʻzbekcha/ўзбекча: Gʻarbiy Afrikadagi Ebola epidemiyasi
srpskohrvatski / српскохрватски: Epidemija ebole u Zapadnoj Africi 2014.