Ebola virus is the cause of a viral hemorrhagic fever disease. The outbreak of ebola virus disease evd continues to spread through west africa. History of ebola virus disease error processing ssi file. Although agents that cause viral hemorrhagic fever syndrome constitute a geographically diverse group of viruses, all of those identified to date are rna viruses with a lipid envelope, all are considered zoonoses, all damage the microvasculature resulting in. Epidemiology of epidemic ebola virus disease in conakry. Hepatitis b virus hbv is a serious public health problem worldwide and major cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma hcc. Common clinical features sudden onset of fever, malaise, myalgia, diarrhoea, hypotension and shock. 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. Vomiting, diarrhoea and rash usually follow, along with decreased function of the liver and kidneys. Sep 09, 2014 withdrawn ebola virus disease epidemiological update. Incidence, transmission, distribution, and control of diseases in a population.
Ebola was first identified in 1976 near the ebola river in the country now known as the democratic republic of the congo. The viruses infecting musa differ in their biology, mode of transmission and epidemiology, and these differences have important practical implications for the control of the diseases caused by these viruses. Aug 23, 2018 please use one of the following formats to cite this article in your essay, paper or report. Phe publications gateway number 2015463 pdf, 952kb, 7 pages this file. Estimates of the basic reproduction number r 0 for sierra leone vary between 1. Pdf ebola virus epidemiology, diagnosis and control. Introduction current outbreak of ebola virus ebov in west africa can be described as most severe public health emergency in modern times 1. Ebola virus disease evd is a rare and deadly disease in people and nonhuman primates. Ebola virus epidemiology, transmission, and evolution during.
Ebola virus disease evd, also known as ebola hemorrhagic fever ehf, is a disease of humans and other primates caused by ebola viruses. Transmission dynamics and control of ebola virus disease evd. Since the first report of evd in march 2014, the number of cases has increased rapidly, with the fatality rate of 50%. Here, we propose a hypothesis of the evolutionary history of ebola virus which will be helpful. Ebola virus disease evd in west africa was first reported during early march 2014 in guineas 3 southeastern prefectures gueckedou, macenta, and kissidougou, which border liberia and sierra leone. Zaire, sudan and cote divoire cause illness in humans. Ebola virus is named after a small river in zaire now the democratic republic of the congo, drc where the first evd outbreak occurred in 1976. Guinea, sierra leone, and liberia have been the most heavily affected. Virus particles known as virions have at least two parts. The mucinliked region of the ebola virus envelope play a significant role in viral infection in nonhuman primates and.
The virus envelope is composed of viral lipids and proteins and is easily damaged by heat, disinfectants and detergents. In this study, 27 ebola virus strains with complete glycoprotein genes, including five species zaire, sudan, reston, tai forest, bundibugyo, were analysed. Some viruses have a third component, called the virus envelope or outer membrane. The outbreak, first declared in march 2014 in guinea and traced back to the end of 20 baize et al. Initial transmissions in sierra leone were concentrated. Mar 03, 2020 ebola virus is one of at least 30 known viruses capable of causing viral hemorrhagic fever syndrome. The viruses that cause evd are located mainly in subsaharan africa.
Multiorgan dysfunction occurs in severe forms with a mortality up to 90%. 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 epidemiology and evolution in nigeria article pdf available in the journal of infectious diseases 214suppl 3. The evd epidemiology, pathogenesis, and clinical characterization will be discussed in this study. Phe publications gateway number 2015463 pdf, 952kb, 7 pages this file may not be suitable for users of assistive. In march 2014, an outbreak of ebola virus ebola arose in western africa.
Since then, there have been more than 0 cases reported with a mortality rate of approximately 70% in clinically confirmed cases. Ebola is also known as ebola virus disease evd or ebola hemorrhagic fever ehf. 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. Effective control of virus diseases of musa in africa needs to be based on an understanding of the biology and epidemiology of the viruses. Threat to humans, lessons learnt and preparedness plans an update on its 40 years journey article pdf available march 2017.
Chikungunya virus chikv is a mosquitoborne virus responsible for periodic and explosive outbreaks of a febrile disease that is characterized by severe and sometimes prolonged polyarthritis. The 202015 western african ebola virus disease evd epidemic, caused by the ebola virus ebov makona variant kuhn et al. As of march 2016, a total of 28 639 evd cases and 11 316 deaths have been reported in 10 countries. The western african ebola virus epidemic 202016 was the most widespread outbreak of ebola virus disease evd in historycausing major loss of life and socioeconomic disruption in the region, mainly in guinea, liberia and sierra leone.
Although there were cases introduced into other continents, africa is the. Variable patients controls dogs 87% 76% cats 64% 62% rats 80% 77% chickens 78% 73% bats 19% 19%. Ebola virus, first identified in humans in 1976 during outbreaks in zaire and sudan, is native to subsaharan africa. The outbreak started in guinea and rapidly spread to liberia and sierra leone, claiming thousands of lives.
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. The ebov first attacks macrophages and dendritic immune cells. Epidemiology and risk factors for ebola virus disease in. Pdf ebola virus epidemiology and evolution in nigeria. Folarin oa1, ehichioya d1, schaffner sf2, winnicki sm2, wohl s2, eromon p1, west kl3, gladdenyoung a3, oyejide ne4, matranga cb3, deme ab5, james a6, tomkinstinch c3, onyewurunwa k1, ladner jt7, palacios g7, nosamiefan i3. Ebola, also known as ebola virus disease evd, is a viral haemorrhagic fever of humans and other primates caused by ebolaviruses.
Current outbreak is the largest in the history, since discovery of. In march 2014, an outbreak of evd was recognized in guinea which would become the most significant outbreak of haemorrhagic fever in africa to date. Here, we propose a hypothesis of the evolutionary history of ebola virus which will be helpful to investigate the molecular evolution of these viruses. We are a research group at the kemriwellcome trust research programme. We study the seir model with vaccination to see the effect of vaccination on both the spread and control of the disease. Ebola virus epidemiology and evolution in nigeria the. The ebola outbreak epidemiology teamoutbreak of ebola virus disease in the democratic republic of the congo, aprilmay, 2018.
Mar 10, 2015 the outbreak of ebola virus disease evd continues to spread through west africa. The number of potential cases ranges from thousands to millions with mortality rate up to 74% 2. Epidemiology of ebolavirus disease evd and occupational. May 26, 2015 the unprecedented scale of the ebola outbreak in west africa has, as of 29 april 2015, resulted in more than 10,884 deaths among 26,277 cases. Dr darina oflanagan, director, hse health protection surveillance centre presents epidemiology of ebola virus disease at the mater hospital ebola conference in dublin, ireland 121114. Percentage of people in this study who reported the presence of illness among other animals on farm. When an epidemic occurs, health care workers hcw are at great risk of infection when caring for evd patients. The first evd outbreak was reported in the 1970s in zaire now the democratic. Ebola virus is characterized by high lethality, high infectivity, and lack of effective treatment or prophylaxis. The most prevalent ebola virus belongs to the species of zaire ebolavirus, with a fatality rate as high as 90%. Epidemiological and evolutionary analysis of the 2014. Transmission dynamics and control of ebola virus disease. Epidemiology of ebolavirus disease evd and occupational evd.
The 201819 ebola epidemic the democratic republic of the. Folarin oa1, ehichioya d1, schaffner sf2, winnicki sm2, wohl s2, eromon p1, west kl3, gladdenyoung a3, oyejide ne4, matranga cb3, deme ab5, james a6, tomkinstinch c3, onyewurunwa k1, ladner jt7, palacios g7, nosamiefan i3, andersen kg8. Ebola virus is one of the most virulent pathogens known to infect humans. Ebola virus disease evd is a lifethreatening viral disease with a fatality rate ranging from around 30% to 90%. 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. Ebola ebola virus disease ebola ebola virus disease fact sheet. Studies were initiated in the philippines to identify the source of the virus among monkeybreeding and export facilities, to establish surveillance and testing, and to assess the risk and significance of. Jan 06, 2015 dr darina oflanagan, director, hse health protection surveillance centre presents epidemiology of ebola virus disease at the mater hospital ebola conference in dublin, ireland 121114. Epidemiology of nipah virus activity educator materials overview this worksheet complements the short video virus hunter.
This paper analyses the transmission dynamics of ebola virus disease using the modified seir model which is a system of ordinary differential equation. There are five ebola subspecies, four of which are known to cause the disease. It was estimated that approximately 2 billion people have serological evidence of past or present hbv infection. Effective control of virus diseases of musa in africa needs to be based on an understanding of the biology and epidemiology of the viruses involved, and on the availability of reliable methods of virus indexing. More than 350 million are chronic carriers of hbv 1. Ebola virus disease, pathogenesis, clinical presentation, diagnosis, treatment. Over the past 40 years, sporadic ebola virus disease evd outbreaks have occurred mostly in the central african region. Ebola virus epidemiology, transmission, and evolution. Epidemiology of epidemic ebola virus disease in conakry and surrounding prefectures, guinea, 20142015 adriana rico, debra brody, fatima coronado, marc rondy, lena fiebig, andrea carcelen, varough m. We conduct intensive long term studies into population dynamics of viral pathogens informing intervention strategies. Person to person ritual washing of ebola victims at funerals nosocomial transmission transmission from animals 4. Withdrawn ebola virus disease epidemiological update.
This can happen when a person touches the infected body fluids or objects that are contaminated with them, such as medical equipment like needles and syringes. Mar 10, 2015 ebola virus is the pathogen of evd, which is mainly endemic in west africa. Ebolavirus disease evd is a serious infectious disease in humans caused by a virus whose natural reservoirs are thought to be fruit bats of the pteropodidae family. Siegert, springerverlag, heidelberg new york, 161165. The zaire ebolavirus was responsible for the outbreak that started in west africa in 2014. Epidemiology of nipah virus student handout infectious disease revised october 2017. Agent factors agent ebola virus contain singlestrand, noninfectious rna genomes. 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. Ebola virus infection epidemiology bmj best practice. Ebola virus, a rna virus, was discovered in 1976 as zaire ebolavirus and currently is responsible for outbreak in the west africa.
People can get evd through direct contact with an infected animal bat or nonhuman primate or a sick or dead person infected with ebola virus. The exact source of ebola infections remains an open question, and. 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 virus disease pathogenesis, clinical presentation and management abstract. Epidemiology of zika virus, 19472007 bmj global health. It was first reported in march 2014, and was the largest outbreak since the virus was first discovered in. 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 clinical manifestations, diagnosis, treatment, and prevention of ebola virus disease are discussed elsewhere. Based on a nearcomplete sequence sample of cases, they reconstruct the seeding event and the subsequent rapid expansion of the epidemic in sierra leone in may and june 2014. Ebov is one of the most virulent pathogens among the viral haemorrhagic fevers, and case fatality rates up to 90% have been reported.
Over the past 40 years, more than 20 outbreaks have occurred in africa, with most of the known outbreaks occurring in the past 20 years. Epidemiology and prevention of hepatitis b virus infection. Epidemiology of epidemic ebola virus disease in conakry and. The west africa ebola virus species zaire ebolavirus outbreak is the largest in history with sustained transmission in multiple countries. A previous study of ebov makona sequences elucidated viral transmission and evolution during the early stages of the outbreak in sierra leone gire et al. The unprecedented scale of the ebola outbreak in west africa has, as of 29 april 2015, resulted in more than 10,884 deaths among 26,277 cases. Limited ebola virus exchange across the sierra leonean border. Although there were cases introduced into other continents, africa is the endemic. Chikv was first recognized as a human pathogen after it was isolated from the serum of an infected patient during an outbreak of debilitating arthritic. 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. A significant unanswered question has arisen for the scientific and engineering communities, as well as the general public, surrounding ebola virus persistence in the environment and the. The first presumed fatality was in guinea in december 20, and the first cases in sierra leone were detected in may 2014.
Ebola hemorrhagic fever is considered a classic zoonotic disease with persistence of the ebola virus in a reservoir species. Introduction since 1947, zika virus has been identified sporadically in humans in africa and asia. The first cases were recorded in guinea in december 20. Mathematical model of the spread and control of ebola. Other zoonotic viruses, such as hendra and menangle viruses. Ebola subtype reston ebor virus infection was detected in macaques imported into the united states from the philippines in march 1996. Ebola virus is the pathogen of evd, which is mainly endemic in west africa. We describe the epidemiology of evd cases reported in guineas capital, conakry, and 4 surrounding prefectures coyah, dubreka, forecariah, and kindia, encompassing a full year of the epidemic. Prior to the ongoing outbreak, ebola virus disease. In 2014, ebola virus disease evd in west africa was first reported during march in 3 southeastern prefectures in guinea. The most common species of ebola virus responsible for outbreaks is the zaire ebolavirus, the second most common species being the sudan ebolavirus. The numerical analysis is done using matlab ode 45 which uses runge kutta method of fourth order. Symptoms may appear anywhere from 2 to 21 days after exposure to ebola virus, though 810 day. Ebola haemorrhagic fever ehf is a febrile haemorrhagic illness of which there are four distinct subtypes.
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