Outbreak The 2013–2016 outbreak, caused by Ebola virus (EBOV), was the first anywhere in the world to reach epidemic proportions.
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, per media reports, included local burial customs of washing the body and the unprecedented spread of Ebola to densely populated cities. It is generally believed that a one or two-year-old boy, later identified as
Emile Ouamouno, who died in December 2013 in the village of
Méliandou in Guinea, was the
index case. These early cases were diagnosed as other conditions more common to the area and the disease had several months to spread before it became recognised as Ebola. By late May, the outbreak had spread to
Conakry, Guinea's capital—a city of about two million people. The outbreak then spread to Sierra Leone and progressed rapidly. By 17 July, the total number of suspected cases in the country stood at 442, surpassing those in Guinea and Liberia. By 20 July, additional cases of the disease had been reported by the media in the
Bo District, while the first case in
Freetown, Sierra Leone's capital, was reported in late July. As the epidemic progressed, a small outbreak occurred in Nigeria that resulted in 20 cases and another in Mali with seven cases. Four other countries (Senegal, Spain, the United Kingdom and the United States) also reported cases imported from Western Africa, which were quickly isolated and led to no other infections, with the exception of the US. 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. On 8 April 2015, the WHO reported a total of only 30 confirmed cases, and the weekly update for 29 July reported only seven new cases. Cases continued to gradually dwindle and on 7 October 2015, all three of the most seriously affected countries, per media reports, recorded their first joint week without any new cases. However, sporadic new cases were still being recorded, frustrating hopes that the epidemic could be declared over. On 31 March 2015, one year after the first report of the outbreak, the total number of cases was over 25,000—with over 10,000 deaths. As the main epidemic was coming to an end in December 2015, the UN announced that 22,000 children had lost one or both parents to Ebola. On 14 January 2016, after all the previously infected countries had been declared Ebola-free, the WHO reported that "all known chains of transmission have been stopped in Western Africa", but cautioned that further small outbreaks of the disease could occur. The following day, Sierra Leone confirmed its first new case since September 2015. In February 2015, Guinea recorded a rise in cases; health authorities stated that this was related to the fact that they "were only now gaining access to faraway villages", where violence had previously prevented them from entering. On 14 February, violence erupted and an Ebola treatment centre near the centre of the country was destroyed. Guinean
Red Cross teams said they had suffered an average of 10 attacks a month over the previous year; MSF reported that acceptance of Ebola education remained low and that further violence against their workers might force them to leave. Resistance to interventions by health officials among the Guinean population remained greater than in Sierra Leone and Liberia, per media reports, raising concerns over its impact on ongoing efforts to halt the epidemic; in mid-March, there were 95 new cases, and on 28 March, and a 45-day "health emergency" was declared in five regions of the country. On 25 May, six persons were placed in prison isolation after they were found travelling with the corpse of an individual who had died of the disease. On 1 June, it was reported that violent protests in a north Guinean town at the border with
Guinea-Bissau had caused the Red Cross to withdraw its workers. In late June 2015, the WHO reported that "weekly case incidence has stalled at between 20 and 27 cases since the end of May, whilst cases continue to arise from unknown sources of infection, and to be detected only after
post-mortem testing of community deaths". On 29 July, a sharp decline in cases was reported; On 28 October, an additional three cases were reported in the
Forécariah Prefecture by the WHO. On 6 November, a media report indicated
Tana village to be the last known place with Ebola in the country, and on 11 November, WHO indicated that no Ebola cases were reported in Guinea; this was the first time since the epidemic began that no cases had been reported in any country. On 17 November, the last Ebola patient in Guinea had recovered, and was discharged from the hospital on 28 November. On 29 December 2015, the WHO declared Guinea Ebola-free. On 17 March 2016, the government of Guinea reported that two people had again tested positive for Ebola virus in
Korokpara. On 19 March, it was also reported by the media that another individual had died due to the virus at the treatment centre in
Nzerekore, consequently, the country's government quarantined an area around the home where the cases took place. On 22 March, the media reported that medical authorities in Guinea had quarantined 816 suspected contacts of the prior cases; the same day, Liberia ordered its border with Guinea closed. On 29 March, it was reported that about 1,000 contacts had been identified, and on 30 March three more confirmed cases were reported. On 1 April, it was reported by the media, that possible contacts, which numbered in the hundreds, had been given an experimental vaccine using a
ring vaccination approach. On 5 April 2016, it was reported via the media, that there had been nine new cases of Ebola since the virus resurfaced, out of which eight were fatal; on 1 June, after the stipulated waiting period, the WHO again declared Guinea Ebola-free. In September 2016, findings were published suggesting that the resurgence in Guinea was caused by an Ebola survivor who, after eight months of abstinence, had sexual relations with several partners, including the first victim in the new outbreak. The disease was also spread to Liberia. On 11 June Sierra Leone shut its borders for trade with Guinea and Liberia and closed some schools in an attempt to slow the spread of the virus; on 30 July the government began to deploy troops to enforce quarantines. During the first week of November, reports told of a worsening situation due to intense transmission in Freetown. According to the Disaster Emergency Committee, food shortages resulting from aggressive quarantines were making the situation worse, and on 4 November media reported that thousands had violated quarantine in search of food in the town of
Kenema. With the number of cases continuing to increase, an MSF coordinator described the situation in Sierra Leone as "catastrophic", saying, "there are several villages and communities that have been basically wiped out ... Whole communities have disappeared but many of them are not in the statistics." In mid-November, the WHO reported that, while there was some evidence that the number of cases was no longer rising in Guinea and Liberia, steep increases persisted in Sierra Leone. On 15 December the
CDC indicated that their main concern was Sierra Leone, where the epidemic had shown no signs of abating as cases continued to rise exponentially; by the second week of December, Sierra Leone had reported nearly 400 cases—more than three times the number reported by Guinea and Liberia combined. According to the CDC, "the risk we face now [is] that Ebola will simmer along, become native and be a problem for Africa and the world, for years to come". On 17 December
President Koroma of Sierra Leone launched "Operation Western Area Surge" and workers went door-to-door in the capital city looking for possible cases. The operation led to 403 new reports of cases between 14 and 17 December. According to the 21 January 2015 WHO Situation Report, the case
incidence was rapidly decreasing in Sierra Leone. However, in February and March reports indicated another rise in the number of cases. The WHO weekly update for 29 July reported a total of only three new cases, the lowest in more than a year. and one week later the last patients were released. However, a new case emerged on 1 September, when a patient from
Kambia District tested positive for the disease after her death; her case eventually resulted in three other infections among her contacts. On 14 September 2015 Sierra Leone's National Ebola Response Centre confirmed the death of a 16-year-old in a village in the
Bombali District. It is suspected that she contracted the disease from the semen of an Ebola survivor who had been discharged in March 2015. On 7 November 2015 the country was declared Ebola-free. Sierra Leone had entered a 90-day period of enhanced surveillance that was scheduled to end on 5 February 2016, when, on 14 January, a new Ebola death was reported in the
Tonkolili District. Before this case, the WHO had advised that "we still anticipate more flare-ups and must be prepared for them. A massive effort is underway to ensure robust prevention, surveillance, and response capacity across all three countries by the end of March." On 16 January aid workers reported that a woman had died of the virus and that she may have exposed several individuals; the government later announced that 100 people had been quarantined. Investigations indicated that the deceased was a student from
Lunsar who had gone to
Kambia District on 28 December 2015 before returning symptomatic. She had also visited Bombali District to consult a herbalist and had later gone to a government hospital in
Magburaka. The WHO indicated that there were 109 contacts and another three missing contacts, and that the source or route of transmission that caused the fatality was unknown. A second new case—a relative and caregiver of the aforementioned victim—had become symptomatic on 20 January while under observation at a quarantine centre. On 26 January WHO Director-General, Dr Margaret Chan officially confirmed that the outbreak was not yet over; On 8 February the last Ebola patient was also released. On 4 February 2016 the last known case tested negative for a second consecutive time and Sierra Leone commenced another 42-day countdown towards being declared Ebola-free. On 17 March 2016 the WHO announced that the Sierra Leone flare-up was over and that no other chains of transmission were known to be active at that time. By 15 July the country had discontinued testing corpses for the virus.
Liberia In Liberia, the disease was reported in both
Lofa and
Nimba counties in late March 2014. On 27 July,
President Ellen Johnson Sirleaf announced that Liberia would close its borders, with the exception of a few crossing points such as
Roberts International Airport, where screening centres would be established. Schools and universities were closed, and the worst-affected areas in the country were placed under quarantine. With only 50 physicians in the entire country—one for every 70,000 citizens—Liberia was already in a healthcare crisis. In September, the
CDC reported that some hospitals had been abandoned, while those still functioning lacked basic facilities and supplies. In October, the Liberian ambassador in Washington was reported as saying that he feared that his country may be "close to collapse"; By November 2014, the rate of new infections in Liberia appeared to be declining and the state of emergency was lifted. The drop in cases was believed to be related to an integrated strategy combining isolation and treatment with community behaviour change, including safe burial practices, case finding and
contact tracing.
Roselyn Nugba-Ballah, leader of the Safe & Dignified Burial Practices Team during the crisis, was awarded the Florence Nightingale Medal in 2017 for her work during the crisis. In January 2015, the MSF field coordinator reported that Liberia was down to only five confirmed cases. In March, after two weeks of not reporting any new cases, three new cases were confirmed. On 8 April, a new health minister was named to end Ebola in the country and on 26 April, MSF handed the Ebola treatment facility over to the government. On 30 April, the US shut down a special Ebola treatment unit in Liberia. The last known case of Ebola died on 27 March, and the country was officially declared Ebola-free on 9 May 2015. The WHO congratulated Liberia saying, "reaching this milestone is a testament to the strong leadership and coordination of Liberian President Ellen Johnson Sirleaf and the Liberian Government, the determination and vigilance of Liberian communities, the extensive support of global partners, and the tireless and heroic work of local and international health teams." After three months with no new reports of cases, on 29 June Liberia reported that the body of a 17-year-old boy, who had been treated for malaria, tested positive for Ebola. The WHO said the boy had been in close contact with at least 200 people, who they were following up, and that "the case reportedly had no recent history of travel, contact with visitors from affected areas, or funeral attendance." A second case was confirmed on 1 July. After a third new case was confirmed on 2 July, and it was discovered that all three new cases had shared a meal of
dog meat, researchers looked at the possibility that the meat may have been involved in the transfer of the virus. Testing of the dog's remains, however, was negative for the Ebola virus. By 9 July three more cases were discovered, bringing the total number of new cases to five, all from the same area. On 14 July, a woman died of the disease in the county of
Montserrado, bringing the total to 6. On 20 July, the last patients were discharged, and on 3 September 2015, Liberia was declared Ebola-free again. After two months of being Ebola-free, a new case was confirmed on 20 November 2015, when a 15-year-old boy was diagnosed with the virus and two family members subsequently tested positive. Health officials were concerned because the child had not recently travelled or been exposed to someone with Ebola and the WHO stated that "we believe that this is probably again, somehow, someone who has come in contact with a virus that had been persisting in an individual, who had suffered the disease months ago." The infected boy died on 24 November, and on 3 December two remaining cases were released after recovering. On 16 December, the WHO reaffirmed that the cases in Liberia were the result of re-emergence of the virus in a previously infected person, and there was speculation that the boy may have been infected by an individual who became infectious once more due to pregnancy, which may have weakened her immune system. On 18 December, the WHO indicated that it still considered Ebola in Western Africa a public health emergency, though progress had been made. After having completed the 42 days, Liberia was declared free from the virus on 14 January 2016, effectively ending the outbreak that had started in neighbouring Guinea two years earlier. Liberia began a 90-day period of heightened surveillance, scheduled to conclude on 13 April 2016, but on 1 April, it was reported that a new Ebola fatality had occurred, and on 3 April, a second case was reported in
Monrovia. On 4 April, it was reported that 84 individuals were under observation due to contact with the two confirmed Ebola cases. By 7 April, Liberia had confirmed three new cases since the virus resurfaced, and a total of 97 contacts, including 15 healthcare workers, were being monitored. The index case of the new flareup was reported to be the wife of a patient who died from Ebola in Guinea; she had travelled to Monrovia after the funeral but died from the disease. On 29 April, WHO reported that Liberia had discharged the last patient. According to the WHO, tests indicated that the flare-up was likely due to contact with a prior Ebola survivor's infected body fluids. On 9 June, the flare-up was declared over, and the country Ebola-free.
Western African countries with limited local cases Senegal In March 2014,
Senegal closed its southern border with Guinea, but on 29 August, the health minister announced the country's first case, who was being treated in a
Dakar hospital. The patient was a native of Guinea who had travelled to Dakar, arriving on 20 August. No further cases were reported, and on 17 October 2014, the WHO officially declared that the outbreak in Senegal had ended. On 22 September 2014, the Nigerian health ministry announced, "As of today, there is no case of Ebola in Nigeria." According to the WHO, 20 cases and 8 deaths were confirmed, including the imported case, who also died. Four of the dead were health workers who had cared for the index case. The WHO's representative in Nigeria officially declared the country Ebola-free on 20 October 2014, stating it was a "spectacular success story". Nigeria was the first African country to be declared Ebola-free. This was largely due to the early quarantine efforts of Dr.
Ameyo Stella Adadevoh.
Mali On 23 October 2014, the first case of Ebola virus disease in
Mali was confirmed in the city of
Kayes—a two-year-old girl who had arrived from Guinea and died the next day. Her father had worked for the Red Cross in Guinea and also in a private health clinic; he had died earlier in the month, likely from an Ebola infection contracted in the private clinic. It was later established that several family members had also died of Ebola. The family had returned to Mali after the father's funeral. All contacts were followed for 21 days, with no further spread of the disease reported. On 12 November 2014, Mali reported deaths from Ebola in an outbreak unconnected with the first case in Kayes. The first probable case was an
imam who had fallen ill on 17 October in Guinea and was transferred to the Pasteur Clinic in Mali's capital city,
Bamako, for treatment. He was treated for kidney failure but was not tested for Ebola; he died on 27 October and his body returned to Guinea for burial. A nurse and a doctor who had treated the imam subsequently fell ill with Ebola and died. The next three cases were a man who had visited the imam while he was in hospital, his wife and his son. On 22 November, the final case related to the imam was reported—a friend of the Pasteur Clinic nurse who had died from the Ebola virus. On 12 December, the last case in treatment recovered and was discharged, "so there are no more people sick with Ebola in Mali", according to a Ministry of Health source. On 18 January 2015 the country was declared Ebola-free. She was treated and released from hospital on 24 January 2015. On 8 October, she was readmitted for complications caused by the virus. On 14 October, her condition was listed as "critical" and 58 individuals were being monitored and 25 received an experimental vaccination, being close contacts. On 21 October, it was reported that she had been diagnosed with
meningitis caused by the virus persisting in her brain. On 12 November, she was released from hospital after making a full recovery. However, on 23 February, Cafferkey was admitted for a third time, "under routine monitoring by the Infectious Diseases Unit ... for further investigations".
Italy On 12 May 2015, it was reported that a nurse, who had been working in Sierra Leone, had been diagnosed with Ebola after returning home to the Italian island of
Sardinia. He was treated at
Spallanzani Hospital, the national reference centre for Ebola patients. On 10 June, it was reported that he had recovered and was released from the hospital.
Spain On 5 August 2014, the
Brothers Hospitallers of Saint John of God confirmed that Brother Miguel Pajares, who had been volunteering in Liberia, had become infected. He was evacuated to Spain and died on 12 August. On 21 September it was announced that Brother Manuel García Viejo, another Spanish citizen who was medical director at the
St John of God Hospital Sierra Leone in
Lunsar, had been evacuated to Spain from Sierra Leone after being infected with the virus. His death was announced on 25 September. In October 2014, a nursing assistant, Teresa Romero, who had cared for these patients became unwell and on 6 October tested positive for Ebola, making this the first confirmed case of Ebola transmission outside of Africa. On 19 October, it was reported that Romero had recovered, and on 2 December the WHO declared Spain Ebola-free.
United States On 30 September 2014, the CDC declared its first case of Ebola virus disease.
Thomas Eric Duncan became infected in Liberia and travelled to
Dallas, Texas, on 20 September. On 26 September, he fell ill and sought medical treatment, but was sent home with antibiotics. He returned to the hospital by ambulance on 28 September and was placed in isolation and tested for Ebola. He died on 8 October. Two cases stemmed from Duncan, when two nurses that had treated him tested positive for the virus; they were declared Ebola-free on 24 and 22 October, respectively. A fourth case was identified on 23 October 2014, when
Craig Spencer, an American physician who had returned to the United States after treating Ebola patients in Western Africa, tested positive for the virus. Spencer recovered and was released from hospital on 11 November.
Countries with medically evacuated cases Many people who had become infected with Ebola were
medically evacuated for treatment in
isolation wards in Europe or the US. They were mostly health workers with one of the NGOs in Western Africa. Except for a single isolated case in
Spain, no secondary infections occurred as a result of the medical evacuations. The
US accepted four evacuees and three were flown to Germany. France, Italy, the Netherlands, Norway, Switzerland, and the United Kingdom
received two patients (and five who were exposed).
Unrelated outbreak in the Democratic Republic of the Congo In August 2014, the WHO reported an outbreak of the Ebola virus in the
Boende District, part of the northern
Équateur province of the Democratic Republic of the Congo (DRC), where 13 people were reported to have died of Ebola-like symptoms. Genetic
sequencing revealed that this outbreak was caused by the Zaire Ebola species, which is native to the DRC; there have been seven previous Ebola outbreaks in the country since 1976. The virology results and epidemiological findings indicated no connection to the epidemic in Western Africa. The WHO declared the outbreak over on 21 November 2014, after a total of 66 cases and 49 deaths. == Virology ==