The virus is transmitted to people from wild animals and then spreads in the human population through humantohuman transmission. Ebola virus disease evd is a severe, often fatal, viral disease. Ebola virus disease pathogenesis, clinical presentation and management abstract. Ebola is a rare but deadly virus that causes fever, body aches, and diarrhea, and sometimes bleeding inside and outside the body.
It has been isolated from bats and causes a similar syndrome to ebola virus infection. The pathogenesis of ebola hemorrhagic fever sciencedirect. Evd was first identified in 1976 near the ebola river in the democratic republic of congo. Ebola virus information ebola virus net outbreak news. Molecular mechanisms of ebola pathogenesis leukocyte biology. The challenges of treating ebola virus disease with. Ebola virus infection epidemiology bmj best practice. There have been several ebola outbreaks, including the 20142016 unprecedented epidemic in africa. The rapid progression of ebola virus infection has further complicated the control of this disease, affording little. Health care professionals discovered ebola in 1976. Outbreaks have been identified yearly for the past 3 years in.
In the late 1970s, the international community was again startled, this time by the discovery of ebola virus as the causative agent of major outbreaks of hemorrhagic fever in the democratic republic of the congo drc and sudan. 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. Cheepsattayakorn a, cheepsattayakorn r 2015 ebola virus disease. Attapon cheepsattayakorn, 1oth zonal tuberculosis and chest disease center, 143 sridornchai road. Ebola virus disease, pathogenesis, clinical presentation, diagnosis, treatment. Currently, there are no approved vaccines or postexposure therapeutics. Ebola virus ebov belongs to the filoviridae family and is responsible for a severe disease characterized by the sudden onset of fever and. Ebola virus disease evd, or simply ebola, is a viral haemorrhagic fever of humans and other primates caused by ebolaviruses. Transmission electron micrograph showing some of the ultrastructural morphology displayed by an ebola virus virion centers for disease control and prevention. The average ebola case fatality rate is around 50%. The disease was first identified in 1976 during two simultaneous outbreaks in subsaharan africa, one in nzara and the other in yambuku, a village near the ebola river, from which the disease takes its name.
Without a specific treatment, management of patients with ebola virus disease consists of the provision of supportive and, as required and when possible, critical care, on the basis of the pathophysiological similarities between, on the one hand, ebola virus disease and, on the other hand, septic and possible hypovolaemic shock. 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. Ebola virus causes acute hemorrhagic fever leading to up to 90% lethality. The natural reservoir host of ebola viruses remains unknown. Current outbreak is the largest in the history, since discovery of. It is unknown if bombali virus, which was recently identified in bats, causes disease in either animals or people. Currently, there are evd outbreaks in several western african nations, including guinea, liberia, sierra leone and parts of nigeria. This fact sheet sets out the recommendations of the comite sur les infections nosocomiales du quebec cinq2 for ebola virus disease prevention and control measures for quebec hospitals. The filoviruses, ebola virus ebov and marburg virus marv, are amongst the deadliest viruses that cause disease in humans with reported case fatality rates of up to 90% in some outbreaks. The glycoproteins of ebola virus are thought to play important roles in pathogenesis. International scientific teams that arrived to deal with these highly. The ebov first attacks macrophages and dendritic immune. It contains information on the west saharan response to ebola as well as highlights from the field in west africa from dr.
Ebola, also known as ebola virus disease evd, is a viral haemorrhagic fever of humans and other primates caused by ebolaviruses. In advanced ebola virus infected cases, they usually reveal hypotension, tachycardia, hiccup, hepatosplenomegaly, confusion, and seizures 2. Replication of the virus in monocytes triggers the release of high levels of inflammatory chemical signals. 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. Ebola virus disease evd is a rare but serious disease caused by infection of the ebola virus. Transmission electron micrograph showing some of the ultrastructural morphology displayed by an ebola virus virion centers for disease control and. Four of the five known ebolaviruses, including ebov, cause a severe and often fatal hemorrhagic fever in humans and other mammals, known as ebola virus disease evd. From origins to outbreak covers ebola virus disease in its entirety from its origins through major outbreaks in the past to the present day outbreak. Ebola virus causes lethal hemorrhagic disease in humans,yet there are still no satisfactory biological explanations to account for its extreme virulence. Well, now ebola has likely spread to more than one person in the area. 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. Early supportive care with rehydration, symptomatic treatment improves survival. Ebola viruses ebovs and marburg viruses marvs are among the deadliest human viruses, as highlighted by the recent and widespread ebola virus outbreak.
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. Ebola virus was first discovered in 1976 near the ebola river in what is now the democratic republic of the congo. The clinical manifestations, diagnosis, treatment, and prevention of ebola virus disease are discussed elsewhere. However, in certain parts of the world, ebola virus may spread through the handling and consumption of bushmeat wild animals hunted for food. Pathology of ebola virus disease dr sampurna roy md. Oct 18, 2018 ebola virus cannot spread to others when a person has no signs or symptoms of evd.
The virus is transmitted to people from wild animals and then spreads in the human population through. The cdc claims on their website that the virus poses no significant risk to the united states. It is caused by an infection with one of five known ebola virus species, four of which can cause disease in people. The virus causing this outbreak, the zaire ebolavirus ebov, belongs to the genus ebolavirus which together with the genus marburgvirus forms the family of the filoviridae. The number of potential cases ranges from thousands to millions with mortality rate up to 74% 2.
Ebola virus is an aggressive pathogen that causes a highly lethal hemorrhagic fever syndrome in humans and nonhuman primates. Infection initially presents with nonspecific flulike symptoms such as fever, myalgia, and malaise. 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. Ebola replication overwhelms protein synthesis of infected cells and host immune defenses. All content in this area was uploaded by syed l badshah on apr 21, 2020. In this study will be presented epidemiology and pathogenesis of ebola virus disease including new findings resulting from the. May 29, 2015 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. Ebola virus disease evd, also referred to as ebola hemorrhagic fever, is a severe and often fatal disease in humans and nonhuman primates such as monkeys, chimpanzees, and gorillas the ebola virus causes ebola virus disease, named after a river in the democratic republic of the congo formerly zaire in africa, where it was first recognized.
Signs and symptoms typically start between two days and three weeks after contracting the virus with a fever, sore throat, muscular pain, and headaches. May 23, 2017 ebola virus disease is a serious, often fatal condition in humans and nonhuman primates. Ebola virus disease evd, also known as ebola hemorrhagic fever ehf, is a disease of humans and other primates caused by ebola viruses. Vomiting, diarrhoea and rash usually follow, along with decreased function of the liver and kidneys. Ebola virus disease evd general information what is ebola virus disease. Mar 03, 2020 ebola virus is one of at least 30 known viruses capable of causing viral hemorrhagic fever syndrome. As the virus spreads through the body, it damages the immune system. Ebola is one of several viral hemorrhagic fevers, caused by infection with a virus of the filoviridae. Ebov is one of the most virulent pathogens among the viral haemorrhagic fevers, and case fatality rates up to 90% have been reported. The ebola virus is a member of the filoviridae family genus ebolavirus. Despite the notoriety of ebolaviruses, particularly ebola virus ebov, as prominent viral hemorrhagic fever agents, and the international concern regarding ebola virus disease evd outbreaks, very little is known about the pathophysiology of evd in humans and, in particular, about the human immune correlates of survival and immune memory. Neurological, cognitive, and psychological findings among survivors of ebola virus disease from the 1995 ebola outbreak in kikwit, democratic republic of congo. Marburgvirus infections ebola and marburg virus disease, ebola and marburg hemorrhagic fever, african hemorrhagic fever in africa. Immunology of protection from ebola virus infection.
Chughtai, helping to solve the primary question of whats next and aiding in. Since then, outbreaks have occurred sporadically in africa. Ebola virus ebov, formerly designated zaire ebolavirus is one of five known viruses within the genus ebolavirus. As of june, 2015, about 27 000 people have been infected with ebola virus in west africa, and more than 11 000 have died. After infection, a secreted glycoprotein sgp known as the ebola virus glycoprotein gp is synthesized. Ebola virus, formally called zaire ebolavirus, is a rare. In general, laboratory testing should be kept to the minimum as required. Ebola virus disease, viral haemorrhagic fever, filovirus. Early clinical sequelae of ebola virus disease in sierra leone. Ebola virus disease has a fatality rate of 50% to 90%. Ebola hemorrhagic fever ebola virus disease is a disease caused by four different strains of ebola virus. Ebola hemorrhagic fever ebola virus disease medicinenet. The high virulence of ebov and marv is largely attributed to the ability of these viruses to interfere with the host immune response. Multiorgan dysfunction occurs in severe forms with a mortality up to 90%.
Endothelial cells cells lining the inside of blood vessels. Ebola hemorrhagic fever is a viral disease caused by ebola virus a member of the filoviridae family or filoviruses that results in nonspecific symptoms see symptom section of this article early in the disease and often causes internal and external hemorrhage bleeding as the disease progresses. Apr 09, 2019 ebola virus, formally called zaire ebolavirus, is a rare virus that infects humans and nonhuman animals such as pigs and other primates. Ebola disease ebola disease is a severe, often fatal illness in humans. Marburg virus is the only other member of this group known to cause human infection. Ebola virus, formally called zaire ebolavirus, is a rare virus that infects humans and nonhuman animals such as pigs and other primates. Pdf the structure and pathophysiology of the ebola virus. In comparison with earlier ebola outbreaks mortality have been higher 80 90 percent, but number of cases was a thousand times lower. For information regarding guidance of specimen collection, transport, testing, and submission for puis, see cdcs guidance for collection, transport, testing, and submission of specimens for ebola virus testing, and the accompanying infographic pdf icon pdf 1 page. Ebola virus disease is a serious, often fatal condition in humans and nonhuman primates. Introduction to ebola virus disease world health organization. Since the discovery of ebola virus in 1976 via traditional viral culture techniques and electron microscopy, diagnostic. Ebola virus formerly known as zaire virus, sudan virus, reston virus non human, tai forest virus and bundibugyo virus.
Several us health care personnel working in west africa also became. Several outbreaks have been reported, often related to animal exposure in mines or caves. Pdf the filoviruses, ebola virus ebov and marburg virus marv, are amongst the deadliest viruses that cause disease in humans with reported case. Introduction current outbreak of ebola virus ebov in west africa can be described as most severe public health emergency in modern times 1. Additionally, the virus is not spread through the air, by water, or in general, by food. Ebola virus can be transmitted by direct contact with blood, bodily fluids, or skin of evd patients or individuals who have died of the disease. Ebola virus disease evd is a rare and deadly disease most commonly affecting people and nonhuman primates monkeys, gorillas, and chimpanzees. Ebola virus is one of at least 30 known viruses capable of causing viral hemorrhagic fever syndrome. 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. 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 first cases of ebola virus infection were reported in zaire now known as the democratic republic of the congo in 1976. Endothelial cells, mononuclear phagocytes, and hepatocytes are the main targets of infection. Figure caption and citation for the preceding image starts.
It is one among several viruses within the genus ebolavirus. Ebola disease is a severe, often fatal illness in humans. In late stage of renal involvement, the ebola virus can directly damage to the kidneys or may be disseminated intravascular coagulation 2. These viruses are elongated, filamentous structures of variable length. Ebola virus disease information for clinicians in u. Jul 21, 2019 ebola isnt as contagious as more common viruses like colds, influenza, or measles. August 2016 importance ebolaviruses and marburgviruses are incompletely understood pathogens that. Ebola is a rare but deadly virus that causes fever, body aches, and diarrhea, and sometimes bleeding inside and outside the body as the virus spreads through the body, it damages the immune. Laboratory diagnosis of ebola virus disease plays a critical role in outbreak response efforts.
Ebola virus cannot spread to others when a person has no signs or symptoms of evd. The filoviruses, ebola virus ebov and marburg virus marv, are among the deadliest viruses that cause. The ebola virus causes a disease that kills up to 90 percent of those who contract it, but a promising vaccine could provide protection. Typically, ebola virus infection runs its course within 14 to 21 days. One affects only nonhuman primates monkeys, gorillas, and chimpanzees and pigs.
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