The virus replicates after it penetrates the host cell membrane by binding with glycoproteins spikes and clathrin-mediated endocytosis. Once inside the cell, the virus releases its nucleocapsid into the host cell cytoplasm, where it replicates. Transcription and translation of the viral RNA into viral proteins is initiated by VP30 activating the start gene. Phosphorylation of VP30 by transcribed viral proteins turns of VP30, in this, VP30 seems to be a regulatory protein, and pharmaceutical research is underway to specifically target VP Currently, this process is not fully understood.
Persons or healthcare workers present with sudden fever, nausea, abdominal pain, vomiting, diarrhea, malaise, myalgias, bleeding from mucosal membranes, skin, eyes, nose, ears. Especially those who traveled to or came in close contact with anyone who has traveled to endemic countries with known or active outbreaks of Ebola virus within the last three weeks got infected.
On physical exam, the patient may present with prodromal symptoms and stable or advanced illness and in shock.
The primary and most important survey will be to assess the patient and acquire a good set of vital signs, including temperature, blood pressure, heart rate, oxygen saturation, respiration rate. The cornerstone of management and treatment for patients infected with the Ebola virus and exhibiting symptoms of Ebola virus disease is supportive care. Repeating fluid loss with IV administration of fluids and electrolytes, controlling temperature with antipyretics.
In addition to supportive care, extensive, emergency research during the last Ebola virus outbreak showed promising results. These studies focused on treatment therapies including the use of convalescent plasma, monoclonal antibodies, anti-viral drugs such as remdesivir.
Further prevention of spread, through imposing international travel bans and exit screenings upon departure from countries with active Ebola outbreaks is a critical non-medical intervention. Ebola virus disease should be differentiated from other causes of hemorrhagic fever and common viral illnesses presenting with similar prodromal symptoms and gastrointestinal symptoms.
The rate of recovery depends on early intervention and access to adequate healthcare with the administration of continuous supportive care and close-interval patient reassessment. The main complications caused by the Ebola virus are hemorrhagic fever and multi-system organ failure leading to shock and eventually death.
The dead bodies must be handled with proper PPE as it can still transmit the virus, due to its resistance to moderate temperature changes. It is vital to educate the public to limit the number of cases spread in the community, and hence the public should be educated about the following:. Ebola virus remains a public health crisis. It is a complex virus causing the deadly disease that is difficult to contain. If it were not for the remote and rural locations of outbreaks, the fear of an Ebola pandemic would be more eminent.
The last Ebola virus epidemic revealed the increased need to stay informed on zoonotic, rare diseases. The increasing incidence of Ebola virus outbreaks directly correlates with the risk of a pandemic, with travel being the main vector. Supportive care remains the determining factor for a good prognosis and outcome. Creating Ebola virus disease treatment units ETUs in the hospitals or converting areas to create ETUs, to provide supportive care remains a public health priority.
Adjunct therapy with monoclonal antibodies and anti-virals was successful in reducing mortality from the Ebola virus disease during the recent epidemic. The PALM trial effectively targeted research showing highly targeted monoclonal antibodies were superior to a lesser specific monoclonal antibody and anti-viral remdesivir. This book is distributed under the terms of the Creative Commons Attribution 4.
Turn recording back on. National Center for Biotechnology Information , U. StatPearls [Internet]. Search term. Ebola Virus Paula R. Author Information Authors Paula R. Affiliations 1 Wyckoff Heights Medical Center. Continuing Education Activity The Ebola virus is a contagious, lethal virus causing hemorrhagic fever. Introduction Ebola virus belongs to the Filoviridae family.
Etiology Ebola virus was named after the Ebola River, where it first emerged in Epidemiology The Ebola virus was originally discovered in , considered a rare, exotic disease mostly studied in highly classified laboratories. Pathophysiology Once the virus infects the host, there is an incubation period of 2 to 21 days.
History and Physical Persons or healthcare workers present with sudden fever, nausea, abdominal pain, vomiting, diarrhea, malaise, myalgias, bleeding from mucosal membranes, skin, eyes, nose, ears. Evaluation The primary and most important survey will be to assess the patient and acquire a good set of vital signs, including temperature, blood pressure, heart rate, oxygen saturation, respiration rate.
Laboratory Testing CBC complete blood count. Differential Diagnosis Ebola virus disease should be differentiated from other causes of hemorrhagic fever and common viral illnesses presenting with similar prodromal symptoms and gastrointestinal symptoms.
Hemorrhagic Fever Marburg virus. Prognosis The rate of recovery depends on early intervention and access to adequate healthcare with the administration of continuous supportive care and close-interval patient reassessment.
Complications The main complications caused by the Ebola virus are hemorrhagic fever and multi-system organ failure leading to shock and eventually death. Deterrence and Patient Education It is vital to educate the public to limit the number of cases spread in the community, and hence the public should be educated about the following: Public Health Educate persons in rural areas to recognize the signs and symptoms of the Ebola virus disease.
Education on how the Ebola virus is spread Bodily fluids, sexual contact, cadaverous. Additionally, early discontinuation of a trial may decrease the precision of results with fewer data points. Vaccination strategy is currently limited to a ring approach, 10 45 46 in which only direct and indirect contacts of probable and confirmed Ebola cases, or front-line health workers and humanitarian staff, are targeted. Some challenges have been identified in the provision of vaccination in the DRC, where more than a year only a quarter of known and probable Ebola contacts were traced by national surveillance teams.
The current vaccination strategy works in preallocated vaccination sites and has a fixed number of daily doses. Persisting fears and misconceptions around the vaccine among local communities are probable factors that pose additional challenges for vaccination uptake.
Long before the Ebola crisis, access to healthcare services and safe drinking water and sanitation in Sub-Saharan Africa were inadequate. To date, there are marked inequalities between regions, socioeconomic groups and genders. In most of the EVD outbreaks, most healthcare facilities were unable to safely provide the services needed, as they lacked staff, medicine and health information.
Limited access to screening and diagnosis, poor pre-existing surveillance mechanisms, overstretched isolation facilities, and lack of treatment to reduce morbidity have been described to largely contribute to the uncontrolled transmission of EVD in West Africa and DRC. In the recent outbreak in DRC, the first case was confirmed in Goma, the capital of North Kivu, and a city of one million people.
The patient had to travel from Butembo to Goma to seek healthcare service. People continued to die in their communities, undiagnosed and untreated. In both the West Africa and DRC outbreaks, the countries faced a significant reduction in the utilisation of health facilities, including paediatric all-cause and malaria admissions, maternity admissions, and attendance in the community.
A complex suite of sociocultural and economic factors influence human movement across the landscape and can have critical impacts on outbreak dynamics and the spatial spread of the infectious disease. To some extent, resistance was due to the limited involvement of members of the community in epidemic responses. These factors have been shown to contribute to community mistrust of healthcare systems, and hence poor health-seeking behaviour.
Challenges in EVD control highlight the necessity of broad-based one-health infectious disease surveillance and emergency response practices. Integrating community-based, one-health surveillance in already established initiatives is likely to address EVD outbreak control. One-health approach is likely to provide a good understanding of the drivers of spillover events from forest-dwelling fauna to forest interfacing humans, which will enable Ebola prevention and control at source.
To reduce the risk of wildlife-to-human and human-to-human transmission, public health officials need to emphasise that EVD results from direct contact with blood, secretion and excretion of infected humans or animals, or indirectly through contact with contaminated fomites, environment or objects.
A better understanding of the ecology of wild animals concerning pathogen transmission is critical to the overall control of EVD in Africa. The one-health paradigm provides opportunities for public education and control because EVD is an animal virus that is transmitted to humans. Building early warning indicators and rapid response to adequately prevent or respond to the EVD outbreak is needed.
Scaling up access to medical supplies and vaccine stockpiles is equally important. Available drugs and vaccines should be added to supplies of personal protective effects and biosafety measures and medicine for supportive care that are given to areas at risk of EVD. It is, therefore, important to ensure that tests and laboratory analysis to confirm suspected cases as soon as possible are readily accessible. Although knowledge on EVD may be higher among medical practitioners, 55 low access to an affordable simple test for timely diagnosis and confirmation can result in a widespread outbreak in affected areas.
As the race towards the availability of therapeutic and vaccine development continues, accelerating research and development for novel diagnostic tools, drugs and safe vaccines is important. The decision to stop a clinical trial early must ensure a careful balance between the integrity of the trial and accuracy of the study results versus preventing harm in patients randomised to inferior treatment and the rapid dissemination to broader medical community.
The vaccination that protects both human communities and the fauna they interact with shared immunity can be one of the novel intervention approaches.
Sub-Saharan countries need to improve their disease surveillance systems and scale up access to routine immunisation programmes. Investing in the development and implementation of local and regional therapeutic and immunisation programmes and virus transmission dynamic interaction requires a multipronged approach with the support of effective cold chain, follow-up tracking system, and contextual communication to establish trust and confidence with vulnerable communities.
The health system includes health facilities, medical personnel and numerous stakeholders people, organisations and activities working in a concerted effort with the paramount intention of maintaining, restoring and improving health across both individuals and groups.
The control of EVD is a desire of any region in order to plan and build a resilient health system. Such a system should have a service delivery, health workforce, information, medical products, vaccine and technologies, financing, and good governance to deliver high-quality and efficient health services. Currently, outbreak relief focuses on short-term assistance delivered by multiple organisations.
The long-term solutions would be to make primary healthcare the centre platform of response. Scaling up contextually diagnostic and care access at the point of need is essential to improving the quality of life and productivity of vulnerable populations.
Important components such as governance, leadership and funding are needed to improve medicine access and logistics, human resource capacity for healthcare services delivery, and information technology uptake in health system strengthening. Social science approaches such as anthropology, working closely with other disciplines, are becoming increasingly important in addressing EVD and other disease outbreaks through surveillance, response, community preparedness and health system strengthening.
Local practices in caring for the sick at home and in health facilities and the perceptions thereof, the handling of the dead and funeral arrangements, the role of complementary medicine and local traditional healers in healthcare, as well as documentation of actual healthcare options used by members of the community need to be addressed before and after epidemics. Equally important is knowledge of local interactions with modern technologies, establishing and re-establishing healthcare relationships, local social structure, community engagement and communication during outbreaks.
Community engagement and participation are an important factor in the appropriate containment of an outbreak and in preventing its further transmission. Application of appropriate and effective risk communication strategies in improving dissemination and uptake of public health messages is also critical to the achievement of this goal. The findings of this review advocate the need to develop a strategy to reduce transmission between human beings and wildlife through a shared commitment, as part of the solution to the future control of EVD outbreaks.
Current EVD control measures such as case management, vaccination, active surveillance, case identification and isolation, and strategic community engagement have helped to contain outbreaks, but many people still die and more epidemics are likely to occur in the previously affected and new geographical areas.
To improve the situation, research on the role of wildlife in the transmission of EVD should be undertaken. There is also a need to accelerate research and development for novel diagnostic tools, drugs, and safe and efficacious vaccines. Wildlife surveillance data on the biodiversity of bats and primates that are found in the region and on the Ebola virus activity in animals and humans should also be included in strategic interventions.
Overall, the success of EVD control requires a balance between bioscience, including the role of epidemiology, health systems, socioanthropology and political science, all brought together to facilitate early detection and response to unusual disease events. Moreover, documenting how diseases are conceptualised is the first step towards understanding local healthcare pathways and unpacking the different meanings attached to infectious diseases in a diversity of communities.
This should include the sources of such knowledge, and the past and current influences on the knowledge of these infectious diseases. A multipronged approach with the support of effective cold chain, follow-up tracking system, and contextual communication to establish trust and confidence with vulnerable communities is an equally important component in attaining national and global health security.
Handling editor: Alberto L Garcia-Basteiro. Contributors: All authors have equally contributed to this work. Funding: The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Map disclaimer: The depiction of boundaries on the map s in this article do not imply the expression of any opinion whatsoever on the part of BMJ or any member of its group concerning the legal status of any country, territory, jurisdiction or area or of its authorities. The map s are provided without any warranty of any kind, either express or implied. Competing interests: None declared. Patient consent for publication: Not required.
Provenance and peer review: Not commissioned; externally peer reviewed. Data availability statement: Data are available upon request.
National Center for Biotechnology Information , U. BMJ Glob Health. Published online Mar 8. Author information Article notes Copyright and License information Disclaimer. Corresponding author. Correspondence to Dr Sima Rugarabamu; gro.
No commercial re-use. See rights and permissions. Published by BMJ. This article has been cited by other articles in PMC. Abstract Introduction Ebola virus disease EVD is one of the deadliest haemorrhagic fevers affecting humans and non-human primates. Conclusions Sub-Saharan Africa continues to face considerable challenges in EVD control, whereby there are no significant changes in case fatality rates observed during the past four decades.
Keywords: ebola virus, epidemics, challenges, opportunities, sub-Saharan Africa. Key questions. What is already known? What are the new findings? What do the new findings imply? Introduction Ebola virus disease EVD is a severe, often fatal, illness in humans and non-human primates caused by a highly virulent RNA virus.
Methods Literature search and selection of articles An internet search of articles on EVD in Africa that were published from July to July was carried out. Open in a separate window. Figure 1. Data extraction and analysis Data extraction focused on the year of the outbreak, the geographical spread estimated area covered, country and region , the strain of the virus involved, the number of cases and deaths, case fatality rate, the challenges, and management used to control the situation.
Results The internet search retrieved a total of articles. Figure 2. Map showing the 11 African countries affected by Ebola virus disease since Table 1 EVD outbreaks, virus type, morbidity, mortality and case fatality rate in affected countries. Context of EVD Different underlying drivers including natural susceptibility of hosts, human economically driven environmental changes and the efficiency of healthcare systems have been described as factors that resulted in EVD outbreaks.
Figure 3. Table 3 OR for case fatality rate of Ebola virus disease according to period. Challenges and opportunities in EVD control Challenges in the detection and containment of EVD outbreaks include epidemiological and ecological, health system, and sociocultural factors table 4.
Table 4 Challenges and opportunities for future prevention and control of EVD outbreak. Factor Challenge Opportunity Action Epidemiological and ecological factors Ebola viruses are endemic in central and western African rainforests.
Known EVD endemic country. Establishing the magnitude of EVD in endemic countries. Health system factors Limited laboratory capacities. Weak surveillance systems. Lack of effective therapeutics and vaccines. Inadequate budget for the healthcare system. Availability of molecular and serological laboratory techniques. Adoption of one-health surveillance.
Improving self-regulation. Key assumptions in analysis of phylogenetics and of the ecology and drivers of Ebola virus EBOV spillover from wildlife hosts such as bats need to be reassessed. More collaborative, respectful approaches with local communities are needed to understand the origins of outbreaks, to address them and to support rather than stigmatise sufferers and survivors. New research finds that the outbreak of Ebola virus disease EVD in Guinea originated in viral resurgence from a persistently infected survivor from the major — epidemic 5—7 years ago 1 prompting an urgent need to re-evaluate whether past EVD epidemics hitherto considered as independent zoonotic spillovers may have had similar origins.
Here, we reconsider local accounts from the West African epidemic that trace its origins to people, dismissed until now as implausible. We thus reinterpret existing scientific accounts of other alleged spillovers, finding that several past outbreaks probably originated in persistent infections over even longer latency.
She had come from the diamond region of Sefadou in nearby Sierra Leone immediately before the outbreak in December , but had first visited several months earlier after being referred to the healer by doctors at Gueckedou hospital.
The healer said that Fanta suffered from Gnangafoo in his Kissi language, for which he was a specialist. Understood usually as a socially caused affliction, this manifests in itchy skin over much of the body and hair loss; Fanta had these symptoms. After recovering somewhat, Fanta left for Sierra Leone but returned to finish treatment just prior to the outbreak.
The residential community health-worker explained how:. In my humble opinion, it is a certain Fanta … who brought us this illness. She suffered from a severe skin complaint that she came to treat here. She was healed. She left back to Sierra Leone and then returned for a second time. She recovered initially. A few days later deaths struck the family. Six died rapidly in the family that welcomed Fanta. Villagers told DM, too, that Fanta was linked to a diamond dealing or mining family across the border.
Researchers who traced EVD to Meliandou heard narratives concerning Fanta but rejected them as she had no Ebola symptoms as then known, and had arrived with Gnangafoo months before the outbreak, far longer than the EVD incubation and infection period.
It was then believed that Ebola patients either died or recovered, clearing active virus from their body. This reasoning cannot now be upheld. First, the symptoms that brought Fanta to Meliandou are now known to be common sequelae of post-Ebola syndrome. Modes of Ebola virus EBOV persistence and latency are inadequately known but are associated with immune-privileged organs.
Published research on persistence in women and children is lacking but EBOV genomic material in semen can correlate with eye and joint pain 9 and has also been detected in asymptomatic survivors and even following multiple prior negative samples. Given the new Guinea evidence of flare-up over much longer timescales, it is important to reassess whether some past outbreaks once deemed spillovers are better explained as flare-ups.
The Sudan Ebola virus variant struck the same cotton factory in South Sudan twice in and and the received view of two separate spillovers now seems unlikely, 13 although the phylogenetic evidence needed to confirm this is not available.
In the two outbreaks in Luebo in DRC in and , the virus was almost identical and must have remained persistent or latent in some way. The outbreak was phylogenetically close to outbreaks in equatorial Africa in , a similarity far greater than expected given mutation rates linked to viral replication.
Baffled, the researchers speculated that the virus was maintained as latent or persistent in an animal host but did not contemplate long-term viral persistence in people. There are wide-ranging implications for science and policy. That many outbreaks may originate in flare-ups does not negate the possible origins of EVD epidemics in spillover from animal reservoirs, but does demand questioning of the balance between these explanations.
While some outbreaks may be new spillovers, and the circulation of multiple EBOV variants in diverse animal reservoirs with potential to spillover as claimed by researchers in 20 suggests this, it is increasingly clear that other outbreaks are from latency.
And whereas most research effort to date infers latency in animal reservoirs, the new evidence from Guinea demands a refocusing on the significance and mechanisms of latency in people. Tilting the balance towards flare-ups, including those at the decadal timescale, suggests that EVD should be reconceived less as a series of discrete epidemics, but more as an already endemic disease although usually in latent form from which outbreaks occur linked to resurgence, some of which become epidemics.
Further research will need to take local accounts and their social underpinnings far more seriously, triangulating with advances in phylogenetic and ecological analysis. There are new challenges for phylogenetic analysis to explore the implications of latency in people, including the possibility of resurgence after many decades or even across generations.
Ecological analysis mapping environmental and demographic drivers of spillover by associating outbreaks with deforestation and encroachment on wildlife must be revisited.
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