Laboratory diagnosis of ebola virus disease plays a critical role in outbreak response efforts. The transmembrane form of gp targets the ebola virus to cells that are relevant to its pathogenesis. Ebola disease ebola disease is a severe, often fatal illness in humans. The pathogenesis of human ebola virus disease evd is complex. The 202015 west african epidemic, by far the most geographically extensive, most fatal, and longest lasting epidemic in ebola s history, presented an enormous international public health challenge, but it also provided insights into ebola s pathogenesis and natural history, clinical expression, treatment, prevention, and control. May 29, 2015 the knowledge about ebola dependent pathogenesis is limited owing to the need of work into biosafety level 4 bsl4 laboratories and this represents a significant barrier for experimental study. Epidemiology, pathogenesis, and clinical manifestations of. Increasingly frequent outbreaks and the placement of ebov in the category a list of potential biothreat agents have boosted interest in this virus. The average ebola case fatality rate is around 50%. Although the primary source of infection is unknown, the epidemiologic mode of transmission is well defined. Clinical manifestations and diagnosis of ebola virus disease.
Evd is characterized by high levels of virus replication and dissemination, dysregulated immune responses, extensive virus and hostmediated tissue damage, and disordered coagulation. Multiorgan dysfunction occurs in severe forms with a mortality up to 90%. Keywords ebola virus disease, viral haemorrhagic fever, filovirus, pathogenesis, treatment introduction on 8 august 2014 the world health organisation who declared the ebola virus disease evd outbreak in. Ebola virus ebov causes severe haemorrhagic fever leading to up to 90% lethality. Ebola is a rare but deadly virus that causes fever, body aches, and diarrhea, and sometimes bleeding inside and outside the body. Tissue and cellular tropism, pathology and pathogenesis of. Ebola virus disease, viral haemorrhagic fever, filovirus.
Ebola ebo virus causes severe disease in humans, with the hemorrhagic syndrome and a high risk of mortality as prominent features of the clinical course. One of the deadliest of epidemic viral diseases, ebola virus disease evd has, since its 1976. Ebola virus ebov belongs to the filoviridae family and is responsible for a severe disease characterized by the sudden onset of fever and malaise accompanied by other nonspecific signs and symptoms. As the virus spreads through the body, it damages the immune. Structure, genome, epidemiology, transmission, replication, pathogenesis, clinical manifestation, lab diagnosis, treatment, prevention and control. Ebola virus is a highly virulent pathogen capable of inducing a frequently lethal hemorrhagic fever syndrome.
Current outbreak is the largest in the history, since discovery of. Marburg virus is the only other member of this group known to cause human infection. As a result, little is understood about how ebola virus is transmitted or how it replicates in its host. Ebov is a virulent pathogen that causes fatal hemorraghic fever in humans and nonhuman primates. The epidemiology and pathogenesis of ebola virus disease will be presented here, including knowledge that emerged during and after the west african epidemic of ebola virus disease. A variety of tests have proven to be specific and useful for ebola virus identification. The index case in this outbreak has not yet been identified. On march 2014 the who notified the outbreak of ebola virus disease evd in guinea, and infection quickly spread to another west african countries including sierra leone, liberia and nigeria. The virus is transmitted to people from wild animals and then spreads in the human population through humantohuman transmission. The virus is a member of the filoviridae family genus ebolavirus. Several outbreaks have been reported, often related to animal exposure in mines or caves. Ebola virus, a rna virus, was discovered in 1976 as zaire ebolavirus and currently is responsible for outbreak in the west africa.
The mucinliked region of the ebola virus envelope play a significant role in viral infection in nonhuman primates and. Ebola, the killer virus infectious diseases of poverty. Jul 22, 2017 19102014 epidemiology, pathogenesis, and clinical manifestations of ebola and marburg virus disease. Use this guidance for more information on clinical presentation and clinical course, pathogenesis, laboratory findings, and evaluation of patients under investigation puis for evd.
The ebov first attacks macrophages and dendritic immune. Multiplatform omics analysis of human ebola virus disease. Geisbertb a biodefense clinical research branch, of. We all hear about ebola virus disease being deadly, but what really makes it so. Ebola virus is filamentous, enveloped measuring 800nm length and 80 nm in diameter which have. A good experimental model is needed to gain insight into the pathogenesis of this disease. Of these, two tested positive for ebola virus, zaire ebolavirus species, by reverse transcription polymerase chain reaction rtpcr on 7 may 2018, and the outbreak was officially declared on 8 may 2018.
After transmission to a new host, the virus enters a cell through a mechanism that has yet to be determined. The role of macrophages and dendritic cells in the pathogenesis of ebola hemorrhagic fever mike braya. Ebola virus ebov belongs to the filoviridae family and is responsible for a severe disease characterized by the sudden onset of fever and. In central and west africa, ebola virus, a member of the filovirus group, has caused sporadic outbreaks of lethal hemorrhagic disease for which no effective. Idm 2004 viral pathogenesis november 20, 2008 2 rna virus families 3 filoviruses ebola and marburg from frederick murphy, cdc from fields virology 5th ed. Once inside the host cells cytoplasm, the filovirus uncoats itself and releases transcriptase, which is contained in the virion. Fruit bats belonging to the pteropodidae family are thought to be the natural hosts of the ebola virus, although the virus has not been isolated yet from bats in natural conditions. The high virulence of ebov and marv is largely attributed to the ability of these viruses to interfere with the host immune response.
Probing into the factors that led to the widespread outbreak, setting forth plans to counter evd cases in developing countries, and devising definitive measures to limit the spread of the disease are essential steps that must be. First recognized near the ebola river valley during an outbreak in zaire in 1976 6, 20, outbreaks have occurred in africa in the ensuing 27 years, with mortality rates ranging from 50 to 90% 26, 28. Mar 15, 2017 pathogenesis of ebola virus disease in pregnancy sources of infection. Others characteristics of ebola virus infections are suppression of immune response and a systemic inflammatory response, which further causes impairment of the vascular, coagulation, and immune systems. Pathology of ebola virus disease dr sampurna roy md. Since its discovery in 1976, ebola virus ebov has caused numerous outbreaks of. In comparison with earlier ebola outbreaks mortality have been higher 80 90 percent, but number of cases was a thousand times lower. Ebola virus is an aggressive pathogen that causes a highly lethal hemorrhagic fever syndrome in humans and nonhuman primates. The index case in this outbreak has not yet been identified and epidemiologic investigations are ongoing, including laboratory testing. Five distinct species of ebola virus have been isolated from various epidemics, mainly in african countries, with the exception of the reston virus that originated in.
Pathogenic mechanisms include implantation of the virus at a body site, replication at the portal of entry, spread to and multiplication within target organs. Ebola virus disease, pathogenesis, clinical presentation, diagnosis, treatment. Riley5 the 2014 to 2016 ebola virus disease evd outbreak in west africa. History of ebola virus disease error processing ssi file. Ebola virus disease is considered to be zoonotic, with occasional spillovers to humans, apes, and possibly other animals. Ebola tissue tropism and pathogenesis the filoviridae journey. Ebola virus formerly known as zaire virus, sudan virus, reston virus non human, tai forest virus and bundibugyo virus.
Pathogenesis of the ebola virus october 3rd, 2014 brain. Ebola virus disease pathogenesis, immunity, vaccination. These viruses cause severe haemorrhagic fevers, with case fatality rates in the range 2590%. To provide updated information about ebola virus disease evd to clinicians working in u. In this study will be presented epidemiology and pathogenesis of ebola virus disease including new findings resulting from the studies linked with 2014 ebola outbreak in west africa. Pathogenesis of the ebola virus october 3rd, 2014 brain im sorry to start your friday off on a somber note, but it appears that the ebola virus has made its way to the united states specifically, dallas, and this has initiated an expected interest and fear in the deadly disease.
The knowledge about ebola dependent pathogenesis is limited owing to the need of work into biosafety level 4 bsl4 laboratories and this represents a significant barrier for experimental study. The epidemiology, pathogenesis, treatment, and prevention of this disease are discussed elsewhere. Since the discovery of ebola virus in 1976 via traditional viral culture techniques and electron microscopy, diagnostic. Analysis of features of pathogenesis in two animal models of. The roles of ebola virus soluble glycoprotein in replication, pathogenesis, and countermeasure development wenjun zhu 1, logan banadyga 1, karla emeterio 1,2, gary wong 3,4 and xiangguo qiu 1 1 national microbiology laboratory, public health agency of canada, winnipeg, mb r3e 3r2, canada. The first outbreak occurred in the democratic republic of congo formerly zaire in a village near the ebola river. Accumulating evidence indicates that the virus actively subverts both innate and. Ebola virus ebov is a member of the filoviridae virus family along with marburg virus marv. Mar 03, 2020 ebola virus is not endemic in the united states, although, during the 20142016 ebola outbreak, several us healthcare personnel were while in africa and were transported to the united states for treatment, in addition to a traveller from liberia who became ill and sought treatment while visiting texas. Ebola virus disease evd, one of the deadliest viral diseases, was discovered in 1976 when two consecutive outbreaks of fatal hemorrhagic fever occurred in different parts of central africa. Typically, ebola virus infection runs its course within 14 to 21 days. For almost 50 years, ebolaviruses and related filoviruses. Clinical manifestations and diagnosis of ebola virus.
Ebola virus disease evd, or simply ebola, is a viral haemorrhagic fever of humans and other primates caused by ebolaviruses. It can be diagnosed by enzymelinked immunosorbent assay elisa. Ebola virus pathogenesis ebola virus is an aggressive pathogen that causes a highly lethal hemorrhagic fever syndrome in humans and nonhuman primates. Im sorry to start your friday off on a somber note, but it appears that the ebola virus has made its way to the united states specifically, dallas, and this has initiated an expected interest and fear in the deadly disease.
Ebola virus mechanism of action 3d medical animation. Ebola virus causes acute hemorrhagic fever leading to up to 90% lethality. Filoviruses, the viral family including ebola virus, are negative. Signs and symptoms typically start between two days and three weeks after contracting the virus with a fever, sore throat, muscular pain, and headaches. Ebola, ebolavirus, epidemic, filovirus, viral disease pathogenesis, viral hemorrhagic fever. Pdf the pathogenesis of ebola virus disease researchgate. Oct 19, 2007 ebola virus is a highly virulent pathogen capable of inducing a frequently lethal hemorrhagic fever syndrome.
See epidemiology and pathogenesis of ebola virus disease and treatment and prevention of ebola virus disease. Ebola viruses and marburg viruses include some of the most virulent and fatal pathogens known to humans. Ebola viruses ebovs and marburg viruses marvs are among the deadliest human viruses, as highlighted by the recent and widespread ebola virus outbreak. Early supportive care with rehydration, symptomatic treatment improves survival. Ebola virus disease evd has mostly affected economically deprived countries as limited resources adversely affect a countrys infrastructure and administration. Several lines of evidence suggest that the viral gp plays a key role in the manifestations of ebola virus infection.
Ebola virus is filamentous, enveloped measuring 800nm length and 80 nm in diameter which have negative sense, single stranded rna genome. The clinical manifestations, diagnosis, treatment, and prevention of ebola virus disease are discussed elsewhere. Lets try and understand how ebola attacks the cells within the body which in turn leads to organ failure and. In this study will be presented epidemiology and pathogenesis of ebola virus disease including new findings resulting from the studies linked with 2014 ebola. First recognized near the ebola river valley during an outbreak in zaire in 1976 6, 20, outbreaks have occurred in africa in the ensuing 27 years, with mortality rates.
Ebola virus disease evd declared as one of the worlds most virulent diseases by who was popularly known as ebola haemorrhagic fever in the past which is usually considered a severe and. The roles of ebola virus soluble glycoprotein in replication. The filoviruses, ebola virus ebov and marburg virus marv, are among the deadliest viruses that cause disease in humans, with reported case fatality rates of up to 90% in some outbreaks. Ebola zaire can develop clinical disease and can transmit this lethal virus to naive pigs and macaques. It has been isolated from bats and causes a similar syndrome to ebola virus infection. Ebola virus disease information for clinicians in u.
We also discuss how the treatment of the infection can benefit from the recent experience of blockingmodulating cell death in human degenerative diseases. The first outbreak occurred in the democratic republic of congo formerly zaire in a village near the ebola river, which gave the virus its name. Ebola virus glycoproteins the glycoproteins of ebola virus are thought to play important roles in pathogenesis. Pdf ebola virus disease evd declared as one of the worlds most virulent diseases by who was popularly known as ebola haemorrhagic.
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