She is the only known human to have been infected with this strain and survived after being hospitalized in Basel, Switzerland. The Bundibugyo strain was responsible for two outbreaks in Uganda in and Democratic Republic of Congo in Sequencing data showed the two outbreaks to be unrelated, with the index case identified as a pregnant woman infected after contact with bush meat. The scale of this outbreak was in keeping with pre outbreaks, with 66 reported cases and 49 deaths [ 19 ].
In addition to the outbreaks described here, isolated individual human cases have been reported including imported cases from Gabon to Johannesburg, South Africa Zaire strain and three laboratory accidents—one in the United Kingdom Sudan strain and two in Russia Zaire strain.
Of note is the discovery that, although there are no previous reports of EVD outbreaks in West Africa, retrospective testing of archived clinical samples during the — outbreak revealed EVD was causing clinical symptoms in Sierra Leone as early as [ 20 ].
While the focus of this article is not the clinical presentation and management of persons with Ebola virus infection, we highlight the key details of EVD in box 1 in order to help contextualize the infection and outbreak response.
This includes a summary of clinical presentation as well as strategies for diagnosis, management and prevention. The outbreak began in Guinea with the first case retrospectively identified as having occurred in late and spread to several other countries, with Sierra Leone and Liberia most severely affected.
The evolution of the — West African outbreak is described below in chronological order, by country. Figure 1 documents a timeline of the major outbreak events in each of the three main affected countries, including epidemic curves. Figure 2 shows a map of the three countries in West Africa with intense transmission, to help visualize the geographical spread outlined.
Table 2 shows a summary of basic country statistics pre-Ebola. Box 2 highlights key outbreak-related definitions used throughout the paper. Timeline of key events with country-specific epidemic curves. Case numbers are total reported confirmed, probable, and suspected cases provided in WHO situation reports throughout the epidemic. We have calculated weekly case number Monday—Sunday.
Where events happened multiple times, only the first occurrence has been shown. Geographical map of Guinea, Sierra Leone and Liberia showing districts and total number of confirmed cases by district. Adapted from WHO [ 21 ]. Basic country statistics from the three main affected countries. Adapted from World Bank data, , unless otherwise stated [ 22 , 23 ]. Any person, alive or dead, suffering or having suffered from a sudden onset of high fever and having had contact with:.
Any suspected case evaluated by a clinician; any deceased suspected case having an epidemiological link with a confirmed case where it is not possible to collect samples for laboratory confirmation. The outbreak is considered ended in a country after 42 days have passed since the last confirmed case has met one of three criteria:. The 42 day count begins on the day following burial. The outbreak in the West Africa subregion was declared over when the 42 day period elapsed in the last affected country.
The rationale for 42 days is based on twice the maximum incubation period for Ebola, as this can be expected to confirm the interruption of human-to-human transmission chains.
After the 42 day period has elapsed, each country should maintain a system of heightened surveillance for a further 90 days, ensuring ongoing EVD surveillance and notification.
During this time a combination of active and passive surveillance should be maintained, ideally integrated with surveillance for other important epidemic-prone diseases. Post-mortem testing and testing of survivor semen samples should also be continued for 90 days.
Passive surveillance should then be continued indefinitely and EVD preparedness plans should be in place and monitored in all countries previously affected by EVD. Epidemiological investigation and blood samples sent to the biosafety level 4 laboratories in Lyon, France and Hamburg, Germany confirmed EVD.
The suspected index case was a two-year old child who fell ill on 2 December and died 4 days later [ 29 ]. A second epidemiological investigation confirmed the source village and index case, but the date of death of the index case was documented as the end of December Other family members rapidly became unwell and died between 13 December and 1 January the index case's mother, sister, and grandmother. Baize et al. Initial transmission chain in Guinea.
HCW, healthcare worker. Adapted from Baize et al. Between December and the identification of Ebola virus as the infectious agent at the end of March , a total of 49 cases met the case definition for EVD, with clinically suspected cases and 79 deaths attributed to EVD on the basis of clinical symptoms. The first cases in the capital city, Conakry, were detected in March However, it was not until May that sustained transmission in Conakry was documented.
Conakry is a city of approximately two million inhabitants located in the west of the country on the coast, approximately km from Meliandou [ 27 ].
By May , the number of cases appeared to be declining in the initial epicentre leading to an MSF treatment facility in Macenta being closed. New cases continued to be reported in other parts of the country, but these were attributed to introductions from Sierra Leone and Liberia.
In time it became apparent that case numbers had not fallen; instead cases had been hidden owing to a number of conspiracy theories which arose when patients were taken to Ebola treatment centres ETCs and died there.
Furthermore, traditional burial practices were forbidden to reduce exposure to infected bodies box 3. However, this violation of cultural beliefs bred fear that the deceased and their relatives would be cursed for failing to perform a proper ceremony. However, one of the main rituals common to all groups is the washing of with bare hands and spending time with the dead body, which is highly infectious in the case of Ebola.
Both of these traditions lead to enhanced transmission of infection and thus, highlight the need for safe burial practices. The populations affected by the Ebola outbreak consisted mainly of Christians and Muslims:.
One of the main challenges in implementing safe burial practices during this epidemic was finding culturally acceptable methods in accordance with safety procedures.
Genuine and open collaboration was required between political, health, tribal and religious leaders. WHO published the new protocols for safe and dignified burials in October , designed in conjunction with affected communities, recognizing the need for the family and religious engagement.
Examples of adaptations to burial practices used in the Ebola outbreak include:. Data during this early phase of the outbreak were irregularly collected and resources were focused on providing clinical care.
Despite multiple requests from MSF and other agencies working in the country, it was not until 8 August that the WHO declared the outbreak a public health emergency of international concern.
The President of Guinea, Alpha Conde, followed suit, declaring a national health emergency. Containment efforts included automatic admission to hospital for suspected cases, compulsory quarantining of Ebola contacts, travel restrictions including enhanced border controls, and preventing dead bodies being transported between towns common for cultural repatriation.
Contravening these restrictions would be subject to law enforcements [ 37 ]. Despite the increased international support that followed these pronouncements, weekly confirmed case numbers remained stubbornly between 75 and between September and December [ 5 ].
In early October MSF reported a spike in cases in the capital, Conakry, with one treatment centre receiving 22 patients in a single day.
As a result, the governor of Conakry banned all cultural celebrations for Eid [ 38 , 39 ]. During October, districts which were previously disease-free started reporting cases including Lola, Kankan and Faranah districts [ 5 ].
The potential cross-border transmission highlighted the need for national border surveillance. Prior to that date, 42 cases of HCW occupation-related death had been reported [ 40 ]. Intense transmission persisted through November and December. Concerns were raised on 20 November when the Red Cross sent blood samples to a testing centre via courier taxi.
The taxi was robbed near the town of Kissidougou with the robbers unwittingly stealing the cooler bag with the infected blood. Despite public appeals, the samples were never recovered [ 41 ]. By mid-December , cases were reported in the northern district of Siguiri bordering Mali [ 5 ] and, one month later, the virus had spread to the western district of Fria for the first time.
In all, 19 districts were reporting transmission events on a weekly basis and transmission in the capital remained high [ 5 ]. All countries struggled to provide the necessary bed capacity to isolate and treat all confirmed, probable, and suspected cases of Ebola, particularly in the early phases of the outbreak.
In total, Guinea had nine ETCs during the outbreak. The first ETCs to be established were run by MSF and the French Red Cross, with many other organizations forming crucial collaborations and providing resources and staff. Setting up an ETC was a huge undertaking and took time, meaning that demand rarely coincided with supply. The number of new reported infections began to fall in early January to approximately 50 cases per week, although this continued to fluctuate [ 5 ].
Throughout February and March transmission was concentrated in the western districts including Conakry, Coyah, and Forecariah. The latter borders Kambia in Sierra Leone which was, by that time, in the midst of its own outbreak see below.
During April—June , the reported country weekly case count declined to approximately 20 cases per week, and fluctuated around this level until a further decrease at the end of July. Transmission remained concentrated in and around the western districts of Conakry and Forecariah, but with cases re-emerging elsewhere, for example in Dubreka and Boke.
During August, Guinea reported only a few cases per week, focused around Conakry and Coyah; and 13 September marked the end of the first week during which no new cases were documented. However, a small number of additional intermittent cases were reported in the Forcariah district between mid-September and late October [ 5 ].
Guinea was first declared Ebola-free on 29 December after a 42 day period without new cases [ 5 ]. Samples were taken from four contacts of the deceased and two tested positive for Ebola the mother and sister of one of the deceased.
Cases were rapidly admitted to a treatment facility together with rapid mobilization of epidemiologists, surveillance experts, vaccinators, social mobilizers, contact tracers and an anthropologist as part of the interagency response team. Guinea was again declared Ebola-free on 1 June [ 5 ]. Despite ultimately having the lowest confirmed number of cases and deaths of the three West African countries with major outbreaks, Guinea witnessed Ebola deaths among cases confirmed, probable, and suspected , of which were laboratory-confirmed cases [ 5 ].
Of the 34 districts in Guinea, 24 were affected by Ebola, in contrast to both Liberia and Sierra Leone in which every district reported cases [ 21 ]. The first cases of EVD were confirmed in Liberia on 30 March , eight days after the outbreak was declared in Guinea: two cases confirmed in Foya district, Lofa County, close to the border with Guinea and Sierra Leone figure 2 [ 45 ] with RNA sequencing confirming that the virus was imported from neighbouring Guinea [ 46 ].
The initial response included enhanced surveillance, contact tracing, training of medical staff, community awareness campaigns, and supplying personal protective equipment to health facilities [ 45 ]. Within the first month of the outbreak in Liberia 13 cases were confirmed, of which 11 died [ 47 ]. The initial wave of infection was effectively contained within Liberia with no new cases reported for nine weeks between 6 April and 7 June [ 27 ].
Phylogenetic analysis supports this, with no future samples of Ebola virus identified from the lineage responsible for the first wave of the outbreak [ 48 ]. This withdrawal later formed part of the wider criticism of the international response to the outbreak [ 52 ]. A new laboratory-confirmed case of EVD was reported on 7 June in Foya district sparking the beginning of the second wave of transmission in Liberia [ 27 ].
Evidence from contact tracing and phylogenetic analysis suggests that the virus was reintroduced from Sierra Leone as it was a distinct viral lineage to previous cases in Liberia [ 48 ].
Genetic sequencing suggests that it was this second distinct viral lineage that was responsible for future intra-country spread, not the lineage responsible for the first importation in March [ 48 ].
The outbreak soon spread to Monrovia, the capital city where a quarter of the country's population live, and claimed the lives of a nurse and the head surgeon from Redemption Hospital, a reminder of the significant risk posed to HCWs during Ebola outbreaks [ 53 , 54 ]. By the end of June suspected cases of EVD had been reported in Liberia, including 52 laboratory-confirmed, with 65 deaths in Lofa, Montserrado and Margibi.
Capacity was minimal and centres filled quickly, the centre in Monrovia having only 40 beds [ 51 ]. Within a month two American volunteers were infected with Ebola—Samaritan's Purse subsequently suspended activities in the country and evacuated its staff, with MSF stepping in to manage the ETCs [ 51 ].
July also saw the Liberian Government close most border points and all schools in order to minimize transmission [ 55 ]. Despite this, by the end of July, case numbers had tripled and EVD had spread to seven of Liberia's 15 counties including Lofa, Montserrado, Margibi, Bomi, Bong, Nimba, and Grand Gedeh ; there were suspected cases and deaths [ 27 ]. Transmission increased rapidly throughout August and September total cases and , respectively , and all but two counties reported cases.
By early September, the total bed capacity in Liberia was , with an estimated deficit of beds in Monrovia alone [ 5 ]. October saw the largest number of new cases in a month, with cases suspected or confirmed, nearly doubling previous case counts [ 47 ]. All 15 counties had now reported at least one confirmed case, with Montserrado, Magibi, Bong and Nimba worst affected, while transmission was decreasing in Foya [ 5 ].
In November , the U. This resulted in the building of new ETCs, an increase in laboratory capacity, air transport of supplies, and enhanced awareness programmes. However, Ebola virus transmission decreased significantly before many of the ETCs had become operational, with some ETCs treating no patients [ 59 ].
Mistrust between communities and authorities was a common theme in all countries affected by the West African outbreak. This was epitomized by protests in Liberia in mid-August Residents of the West Point District tried to dismantle an Ebola screening unit which they viewed as a risk to their safety.
This lead to violent clashes between soldiers and protesters and the eventual quarantining of the whole West Point District [ 60 ]. Mistrust of the government, as well as fear of stigmatization, led some to avoid seeking medical help for suspected EVD and reluctance to engage in surveillance and contact tracing [ 56 ].
In a heavy-handed response, the Liberian Government made it illegal to conceal an Ebola-infected patient, punishable by a prison sentence of 2 years [ 61 ]. The peak in reported cases occurred in September , but by late transmission had begun to decrease. By early January , nine months after the first reported cases in Liberia, approximately new cases were being reported per week, with transmission limited to two counties: Montserrado and Grand Cape Mount [ 47 ].
One additional case was confirmed in Monrovia later in March but led to no additional subsequent infections. Forty-two days later, on 9 May , Liberia was declared Ebola-free [ 5 ]. Liberia was declared Ebola-free three more times, after small clusters of infection in June , November and April The first of these clusters was of six confirmed cases near Monrovia. Genomic sequencing suggested re-emergence from an EVD survivor in Liberia rather than cross-border spread [ 5 ].
The second cluster occurred in Monrovia among three members of the same family. This was also attributed to long-term viral carriage in a survivor. The final cluster occurred in April and was thought to have been imported from Guinea when a woman travelled to Monrovia from Macenta, Guinea, to visit relatives after the death of her husband from EVD. The virus spread to her two sons, but with rapid diagnosis, contact tracing, early treatment and isolation in an ETC, the virus did not spread further [ 62 ].
Liberia was again declared Ebola-free on 9 June The total number of confirmed, probable, and suspected cases in Liberia was 10 laboratory-confirmed , with deaths [ 47 ]. The first case was a young woman in Kenema, Sierra Leone's third largest city, 50 km from the Liberian border and km from the border with Guinea. Given the situation in neighbouring countries, Sierra Leone had already begun an enhanced surveillance programme based in the Lassa fever isolation ward in Kenema General Hospital [ 64 ].
Within a month of the outbreak being confirmed in Sierra Leone, over people were reported infected [ 47 ] and case numbers appeared to be increasing rapidly. Within six months of the first reported case, the outbreak in Sierra Leone peaked November with up to people a week being infected [ 47 ]. Retrospective analyses suggest that the Ebola virus was introduced to Sierra Leone from Guinea more than five months before the first officially reported case. Further genomic analysis suggests two distinct linages of Ebola virus were introduced into Sierra Leone from Guinea in early [ 64 ].
Like many ETCs at this stage of the outbreak, this facility was rapidly overwhelmed. Further beds were provided in the Lassa fever isolation ward at Kenema District Hospital, which was uniquely placed to deal with the emerging threat of EBV.
However, this too was overwhelmed by the sheer number of cases and it was forced to move patients into general medical wards where isolation and infection control were inadequate. More than 40 HCWs from this hospital were infected in [ 67 ], with many of them dying, including Sierra Leone's only national expert on haemorrhagic fevers [ 68 ].
Once the virus was established within Sierra Leone, molecular epidemiological evidence suggests that sustained human-to-human transmission occurred within the country, rather than through repeated cross-border reinfections or recurrent zoonotic events [ 70 ]. Ebola virus appears to have spread long distances following major roads networks, whereas many smaller chains of transmission went unnoted and uncontrolled in remote, isolated villages [ 71 ]. Just as the outbreak in one area was thought to be coming under control, these undetected links surfaced in new geographical areas, causing wave-like spread across the country from east to west.
By September , sustained transmission was reported in the densely populated capital, Freetown [ 72 ]. The spread from the eastern hub to Freetown, which resulted in intense transmission, marked a serious escalation in the outbreak [ 73 ].
A state of emergency was declared and a 3 day national lockdown was imposed in September The lockdown was designed not only to decrease the movement of people, but also to give HCWs time to identify new cases and increase awareness of EVD through door-to-door campaigns [ 75 ]. Subsequently, quarantine restrictions were put in place in high-risk areas; curfews were imposed, including in Freetown, lasting anywhere from 21 days to several months, with restriction of movements between Mass quarantine proved controversial—at one point one third of the population of Sierra Leone was under quarantine [ 77 ].
Aside from the ethical concerns, many felt that mass quarantine measures were ineffective for Ebola as patients are not infectious until they become symptomatic [ 80 ], and they may have been counterproductive by preventing the free movement of necessary medical supplies and personnel [ 81 ].
By October , transmission had spread to the northern district of Koinadugu, the last remaining Ebola-free district of Sierra Leone [ 82 ]. However, by November , the outbreak in the eastern hub had begun to see reduced transmission [ 73 ]. More HCWs were infected and died in Sierra Leone than in any other country, both in absolute numbers and relative proportion of cases terms [ 67 ].
Sierra Leone was the only country in which there were strikes by frontline workers because of working conditions and pay. In late , burial workers went on strike over unsafe working conditions and a lack of hazard pay [ 83 ], in contrast to the relatively generous compensation paid to HCWs and their families in Guinea [ 40 ]. In addition, doctors and nurses withdrew their labour [ 66 ] seeking assurance that a new UK-built treatment centre for HCWs would accept local, as well as international, staff if they became infected [ 84 ].
Despite an apparently well-functioning contact tracing system [ 85 ], cases continued in the north of the country across the first half of , in part fuelled by secret and unsafe burials [ 86 ]. This included the imposition of curfews in both districts 12 June , enhanced surveillance, active contact tracing, intense community engagement and mass quarantine.
With these intense response strategies, the outbreak in Sierra Leone appeared to be coming under control, but despite the strictness of Operation Northern Push [ 88 ] new chains of transmission proved stubbornly resistant to detection. News of a case in Kambia in September —three weeks after the last reported case and with no link to any known chain of transmission—led to a flurry of activity, including the first trial of ring vaccination in Sierra Leone for Ebola virus [ 89 ].
This was in addition to vaccine trials for frontline workers undertaken in Sierra Leone [ 90 ]. After this concerted effort, in November , one year on from the epidemic peak, Sierra Leone was declared free of Ebola virus [ 91 ]. However, two months later in January , a year old woman died of EVD and her carer was subsequently found to be infected. Applying many of the lessons from the previous 18 months, the public health system responded rapidly and effectively, quickly containing the flare-up and preventing spread.
Four months later, and almost 2 years after the first confirmed infection, Sierra Leone was again declared Ebola-free on 17 March [ 92 ]. The outbreak in Sierra Leone claimed the lives of persons and is believed to have infected 14 laboratory-confirmed cases [ 47 ].
Sierra Leone is now the country with the largest number of Ebola cases in history. Several other neighbouring countries had confirmed Ebola infections during this period, all with epidemiological and genetically proven links to the outbreaks in Guinea, Liberia and Sierra Leone.
However, only Nigeria and Mali had foci of local transmission. Table 3 highlights the Ebola infections diagnosed outside Guinea, Liberia and Sierra Leone by country.
In addition, other countries also accepted evacuated cases from West Africa for hospitalization including Germany, France, Switzerland, The Netherlands and Norway. There was also the coincidental, but unrelated, outbreak in DRC which occurred at the same time. October 2-year old girl from Guinea whose father was a Red Cross worker who died—no local transmission.
November Iman from Guinea, thought to have partaken in traditional burial ritual ceremonies across the border in Sierra Leone. Local transmission occurred and six others infected. Liberian national visiting family in Dallas—local transmission to two HCWs. Social, biological and structural drivers of transmission combined during the outbreak to allow a perfect storm with unprecedented and devastating consequences [ ].
This was exacerbated by a failure in the response at both national and international levels. Table 4 outlines the key factors leading to the failure in controlling the outbreak. This section discusses these factors in more detail, with specific focus on the role of interventions on limiting outbreak size.
Emerging diseases such as Ebola often arise from close animal contact at the zoonotic interface. Therefore, it is common for outbreaks to occur in isolated rural areas, and most previous Ebola outbreaks have remained contained in these settings. In the initial phases of this outbreak, disease transmission went undetected and likely led to chains of transmission within the Kissi tribal area that spans the borders of Guinea, Liberia and Sierra Leone figure 4.
The local population is mobile across these three countries, the borders of which are porous, and as a result it accounted for the vast majority of early cases in this outbreak. Online version in colour. Failure to control transmission in the early phases of the outbreak allowed mobile populations and migration to spread transmission chains from rural to urban areas.
Recent studies estimate that population mobility in the major affected countries is seven times higher than elsewhere in the world, thought to be caused by poverty driving mobility as people look for work or food [ ]. The increasing connectivity of distant rural communities [ 85 ] means that outbreaks of emerging diseases are more likely than ever to reach densely populated centres [ , ] such as Freetown, Monrovia, and Conakry.
These major cities provide hubs for international spread [ — ] given that the world is increasingly globalized and infections do not respect national borders [ ].
Guinea, Liberia and Sierra Leone are among the poorest countries in the world, and have only recently emerged from civil wars. Their damaged health infrastructure was ill-equipped to deal with the scale of this outbreak. Pre-outbreak, HCW capacity was already critically low at approximately one or two HCWs per population table 2 , and this was further diminished by the epidemic [ 23 , ]. The non-specific nature of EVD means fast and accurate laboratory diagnosis is essential, yet in rural West Africa both laboratory and human resource capacity was limited.
In the initial stages this led to timely response mechanisms being hindered by a lack of diagnostic facilities. Furthermore, road systems, transportation and telecommunications networks were weak in all three countries, especially in rural settings. This delayed the transportation of patients and diagnostic samples and the dissemination of public information campaigns [ ].
For example, in some settings, clinical samples had to be transported across large geographical areas with poor transport infrastructure, meaning diagnostic confirmation often took several days.
High-risk behaviours and lack of infection control measures around death and traditional burial practices have long been known to propagate transmission events [ 85 ]. One funeral alone is thought to have begun a huge chain of transmission with several hundred infections [ ]. Safe burials were, therefore, integral to the Ebola response—modelling based on the outbreak in Liberia suggested that interrupting funeral transmission could have had the greatest potential impact of all interventions on outbreak prevention [ ].
Despite this, repeated assessments revealed widespread risks in funerals including a lack of trained burial teams, a shortage of burial space, no clear guidelines on collecting diagnostic specimens from the deceased, and a lack of community engagement to facilitate culturally acceptable safe burials [ ]. Funerals in eastern Sierra Leone, for example, are steeped in cultural significance; the strong sense of family and local allegiances, often tied together by marriages and dowries, are thought to have allowed these remote communities to survive through civil war when government safety nets were non-existent.
The practice of taking wives from distant villages saw sisters and close female relatives travelling long distances in order to wash the body of women who died from Ebola according to the Muslim tradition box 3 , providing an important social pathway that facilitates the spread of Ebola to new geographical areas [ 85 ]. This was compounded by widowers travelling back to their deceased wife's home village to complete any outstanding dowry payments though labour, providing further opportunity for onward disease transmission [ 85 ].
New standard operating procedures developed by WHO box 3 were insufficient alone to successfully reduce risk behaviours during funerals; it was only when these social pathways were recognized, acknowledged and addressed that the number of safe and dignified burials met international guidelines and the epidemic curve began to fall [ ]. Prior to this outbreak, the mainstay of interventions to combat Ebola outbreaks were contact tracing and follow-up for exposed contacts, prompt treatment and isolation of suspected and confirmed cases, strict infection control, and safe burial, underpinned by a strong commitment to community engagement [ ].
These measures continued to be effective during the — outbreak, and the epidemic confirmed knowledge and protocols established from previous outbreaks. However, progress in understanding the exact benefit of each intervention is limited owing to a lack of evidence; the decline in cases across all countries coincided with simultaneous implementation of multiple interventions and disentangling the role of each requires further study.
Central to all interventions was the need to work with affected communities not only to effectively serve their needs [ ], but also to enable the development and implementation of culturally acceptable strategies. As described throughout this paper, a failure to engage communities early enough had a detrimental effect on this outbreak response, but when effectively engaged, community interventions played a significant role in curtailing the outbreak. The three affected West African countries have cultures of strong community connectedness, with trust for community leaders far greater than that of government [ ], exacerbated by recent civil unrest.
Acknowledging these social structures and working alongside community networks proved essential for effective outbreak response. Mistrust between the implementing organizations and individuals directly impacted the effectiveness of surveillance, contact tracing, healthcare seeking behaviour, and safe burial initiatives; all individually propagating the spread of the virus [ , ].
Conversely, where achieved, community engagement with strong international support was integral to controlling Ebola; modelling of the outbreak in Liberia concluded that the increase in bed capacity, credited with causing a reduction in disease incidence, was insufficient to bring case numbers down without significant public engagement [ ].
Drawing on conversations with communities in the most affected countries, local experts and international actors, the main steps identified in achieving community engagement in Ebola response efforts include: identifying both male and female community leaders to champion key messages; organizing regular community meetings; using varied communication methods; tailoring global policies to local settings; and involving family members in care actions which do not expose them to increased risk [ ].
Effective community engagement benefited policy-making: strategies designed when incorporating cultural values, customs and concerns of affected communities were more effective [ ]. Implementation also benefited: at various stages of this outbreak, transmission was fuelled by a reluctance of populations to seek care in designated facilities, to engage in adequate contact tracing, to respect quarantine regulations, or to reveal deaths in order to allow safe burial [ ]—all of which improved after programmes of community engagement [ ].
Examples of successful interventions included communities buying megaphones to counter myths related to infection and to encourage people to seek treatment instead of hiding from authorities [ 59 ].
All other policies outlined below must, therefore, be viewed not as isolated technical interventions, but as part of a wider programme of disease control activities, with community engagement chief among these. The ability to identify, and subsequently interrupt, chains of transmission is crucial to the success of containment efforts, and the success of contact tracing is, like all Ebola interventions, determined by the extent to which communities trust and give accurate information to those attempting to curb the outbreak [ ].
One proxy indicator as to the success of contact tracing is the proportion of new confirmed cases who were already being monitored as contacts of known, existing Ebola cases.
These contacts can then be followed up with temperature checks for the 21 day incubation period and receive prompt isolation if diagnosed with Ebola, thereby improving treatment outcomes and reducing exposure to further potential contacts. In fact, modelling from early in the outbreak in Sierra Leone and Liberia identified that contact tracing with prompt isolation and infection control could have a more substantive effect on the epidemic than even potentially curative medical therapies [ ].
Despite this, evidence from Guinea and Sierra Leone suggested that contact tracing was far from adequate at this time—as a result, few new cases were from identified contacts and chains of transmission proved stubbornly difficult to interrupt [ , ]. Alternative approaches focusing on community-based early detection over contact tracing proved more effective in simulations based on epidemic data [ ]. Effective infection control in healthcare facilities is a crucial step in interrupting chains of transmission.
Lack of knowledge and resources to provide effective infection control were major factors leading to an amplification of this outbreak. Transmission was propagated by HCWs who became infected and who inadvertently spread infection to their family members and communities, particularly in the early phase of this outbreak [ 30 ], in a similar pattern to historic outbreaks [ 2 , 8 , 30 ].
Early in the outbreak, the relative risk for acquiring EVD was around times higher for HCWs compared with the general population [ ], although this risk decreased as barrier precautions were more effectively implemented, and personal protective equipment became available [ ].
This is a tragic reminder of the risks frontline HCWs face in weakened and understaffed healthcare systems. National IPC plans were developed and published in each country by late , with IPC task forces established to coordinate infection control efforts. However, progress was slow. For example, in October , in Sierra Leone, almost five months after the first reported case and despite infection control teams being deployed, major gaps in IPC practices remained.
None of the six Sierra Leonean districts visited by a CDC-led monitoring team had standard operating procedures or adequate equipment [ ]. Progress was hindered by delays in importing personal protective equipment and a lack of engagement with community partners [ ]. Thus, effective implementation on the ground was impossible despite extensive training [ ]. The lack of bed capacity in ETCs to isolate and treat patients resulted in a massive inpouring of support to increase treatment facilities.
Offering patients care with stringent infection control, supported by accurate PCR diagnosis, increased willingness to be hospitalized and facilitated contact tracing. ETCs have been integral in the control of previous outbreaks, though never before have they been deployed on this scale [ ].
Illnesses that occurred after July 31, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported. As of September 3, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 24 states.
Since the last update on August 30, 5 additional ill people were reported. Ill persons range in age from less than one year to 92 years, with a median age of 51 years. Illnesses that occurred after July 28, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported.
As of August 29, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 23 states. Since the last update on August 28, 20 additional ill people were reported. Illnesses that occurred after July 24, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported.
As of August 27, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 22 states. Since the last update on August 26, 6 additional ill people were reported.
Illnesses that occurred after July 22, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported. Because many of the more recent cases have been reported from Texas, CDC is collaborating with the Texas Department of Health and Human Services and local public health departments to investigate cases of cyclosporiasis reported among people in Texas.
Public health investigators have interviewed ill people in Texas about their exposures during the 2 weeks before they became ill. These interviews have covered what food they ate and where they ate and purchased their food. On the basis of these interviews, investigators have identified a group cluster of ill people who reported eating at the same restaurant.
A detailed investigation of this cluster is ongoing. This investigation includes listing the different ingredients in the food that was eaten. People who did not get sick but who also ate meals at the same restaurant on the same days as ill people are also being interviewed.
The preliminary analysis of results from this ongoing cluster investigation in Texas does not show a connection to salad mix, leafy greens, and salad mix components produced at Taylor Farms de Mexico. The team also assessed five farms identified through traceback information from the outbreak investigation.
The team found that conditions and practices at these facilities at the time of the assessment were in accordance with known food safety protocols. On August 25, , Taylor Farms de Mexico, with FDA concurrence external icon , resumed production and shipment of salad mix, leafy greens, and salad mix components to the United States.
The firm had voluntarily ceased production and shipment of these products on August 9, The findings in Texas differ from those from earlier investigations in Iowa and Nebraska. In those states investigators linked cyclosporiasis cases acquired after eating in one of multiple restaurants to eating a bagged salad mix from Taylor Farms de Mexico. It is not unusual to recognize outbreaks that happen in the same season but are due to different foods.
As in and in years past , most cases and outbreaks of cyclosporiasis in the United States are detected in spring and summer months. Not all cases during the same time of year are necessarily caused by the same exposure. Although the investigation of cases in is ongoing, available evidence suggests that not all of the cases of cyclosporiasis in the various states are directly related to each other. CDC continues to work with state and local partners and FDA to investigate clusters of illness, food exposures, and sources of food items.
No laboratory tests are available yet that can distinguish different strains of the parasite Cyclospora cayetanensis. CDC and other institutions are working on developing new molecular tools that could distinguish one strain from another. These tools would help public health investigators more quickly determine whether cases of Cyclospora infection are linked.
These tools could also be useful for linking a possible source of infection to illnesses in people. As of August 23, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 22 states.
Since the last update, 1 additional ill person was reported. Illnesses that occurred after July 17, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported. As of August 22, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 22 states. Since the last update, 8 additional ill people were reported.
Illnesses that occurred after July 16, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported. As of August 21, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 22 states. Since the last update, 3 additional ill people were reported.
Illnesses that occurred after July 15, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported. As of August 20, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 22 states. Since the last update, 5 additional ill people were reported. Illnesses that occurred after July 14, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported.
As of August 19, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 20 states. Since the last update, 7 additional ill people were reported.
Illnesses that occurred after July 13, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported. As of August 16, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 20 states. Since the last update, 10 additional ill people were reported. Fifty-five percent of ill persons are female.
Illnesses that occurred after July 10, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported. This could take up to 4 to 5 weeks. As of August 15, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 19 states. Since the last update, 19 additional ill people were reported. Fifty-four percent of ill persons are female. Illnesses that occurred after July 9, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported.
As of August 14, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 19 states. Since the last update, nine additional ill people were reported. Illnesses that occurred after July 6, , might not yet have been reported because of the time it takes between when a person becomes ill and when the illness is reported.
As of August 13, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 19 states. As of August 12, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 19 states.
Since the last update, four additional ill persons were reported. At least 32 people have reported being hospitalized. As of August 9, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 18 states.
Since the last update, 21 additional ill persons were reported. On August 12, , Taylor Farms de Mexico officially informed FDA external icon that, as of August 9, , the company had voluntarily suspended production and shipment of any salad mix, leafy green, or salad mix components from its operations in Mexico to the United States. As of August 7, 5pm EDT , a total of ill persons with Cyclospora infection have been reported from 17 states.
Since the last update, 37 additional ill persons were reported. At least 30 people have reported being hospitalized. Section Navigation. Facebook Twitter LinkedIn Syndicate. Figure 1 Figure 2. Article Metrics. Related Articles. Sunhee Lee and Changhee Lee. The Study. Figure 1 Figure 1. Figure 2 Figure 2. Debouck P , Pensaert M. Experimental infection of pigs with a new porcine enteric coronavirus, CV Am J Vet Res.
PubMed Google Scholar. Diseases of swine. Ames IA : Wiley-Blackwell; Oldham J. Letter to the editor. Pig Farming. Virus Genes. Emerg Infect Dis.
An outbreak of swine diarrhea of a new-type associated with coronavirus-like particles in Japan. Jpn J Vet Sci. J Vet Diagn Invest. Pensaert MB , de Bouck P. A new coronavirus-like particle associated with diarrhea in swine. Arch Virol. Korean Journal of Veterinary Research. Heterogeneity in spike protein genes of porcine epidemic diarrhea viruses isolated in Korea. Virus Res. Lee YN , Lee C. Complete genome sequence of a novel porcine parainfluenza virus 5 isolate in Korea.
Completion of the porcine epidemic diarrhea coronavirus PEDV genome sequence.
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