Ninety percent of these ebolazaire cases, and 50 percent of these ebolasudan cases, resulted in death. This type of work is necessary for the development of vaccines and therapeutic drugs for ebola. Subsequent outbreaks of ebola in uganda, gabon, south africa, sudan and zaire. By january 2016, suspected and confirmed cases had totaled more than 28,600, and reported deaths numbered about 11,300, making the outbreak significantly larger. The two outbreaks were caused by two distinct species of ebola virus named zaire ebolavirus zebov. Ebola is a virus that was discovered back in 1976, but has not failed to grab peoples attention in the recent years 1.
Lessons from the ebola outbreak in west africa the. Ebola returns, and central africas virus hunters are. Visit the ebola outbreak section for information on current ebola outbreaks on march 23, 2014, the world health organization who reported cases of ebola virus disease evd in the forested rural region of southeastern guinea. Stopping the virus in west africa is an investment in keeping it from u. This information was published four days ago on the 15th of january 2016 by who. Unlike past occurrences, which affected remote locations, the current outbreak is. Ebola outbreak in west africa safey emergency system. In the present paper, we used a seir model developed by astacio, et al. Essay on the elusive natural history of ebola viruses intechopen. The recent outbreak of ebola virus disease evd in west africa has highlighted both the importance of rapid and accurate diagnosis of this disease and the challenges around diagnostic testing. The figure above is a map of west africa, showing the wide geographic spread of cases of ebola viral disease during the ongoing outbreak. Ebola outbreak of 201416, also called 2014 ebola outbreak in west africa or ebola outbreak of 2014, outbreak of ebola virus disease that ravaged countries in western africa in 201416 and was noted for its unprecedented magnitude. Since the west africa ebola epidemic, there have been trials for a new vaccine, but currently there is no licensed ebola vaccine.
Ebola has demonstrated that disease threats do not stop at passport control and that health security is national security. Experience tells us that ebola outbreaks can be contained, even. Ebola virus was identified in 1976 after simultaneous, highly lethal outbreaks of hemorrhagic fever occurred in northern zaire now the democratic republic of congo drc and southern sudan, each caused by a different strain of the virus muyembetamfum et al. The natural history of ebola virus in africa sciencedirect. During the fallout from the 2014 ebola outbreak in west africa. However soon after this, a new confirmed case has been identified in sierra leone.
The variety of factors that contributed to the initial undetected spread of ebola virus disease in west africa during 202016 and the difficulty controlling the outbreak once the etiology was identified highlight priorities for disease prevention, detection, and response. Perspectives on west africa ebola virus disease outbreak. An outbreak of ebola virus disease evd in west africa, with onset in early february 2014, is evolving in guinea and liberia. The figure above is a bar chart showing the number of cases of ebola viral disease evd in the ongoing outbreak that were reported from guinea, by week of symptom onset in during 2014. This article is an overview of the many published investigations of how ebola virus circulates in its natural environment, focusing on the viral reservoir, susceptible animal species, environmental conditions favoring interspecies transmission, and how. The outbreak began in guinea in december 201 and later spread to sierra leone, liberia and nigeria. 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. Since ebola virus disease was staff participated in the smallpox eradication program, one identifiedin west africa on march 23, 2014, the centers for disease control and prevention cdc has undertaken the most intensive response in the agencys history. Previous ebola virus outbreaks have been confined to remote regions of. West african ebola virus epidemic timeline of reported.
Combining this result with that of the macroeconomic model, we determine. The first evd outbreak was reported in the 1970s in zaire now the democratic. On 1 august 2018, the democratic republic of the congo ministry of health declared an outbreak when 4 individuals tested positive for the ebola virus. Who responds to ebola virus disease outbreak in west africa. These factors include occurrence in a region recovering from civil instability and lacking experience with ebola. The first cases were recorded in guinea in december 20. Infectious%20diseases%20and%20impact%20assessments. Ehf has been associated with large human outbreaks, with case fatality rates for zebov as high as 90% 7, 8, 9. Until 20, most outbreaks occurred in the central africa region, including zaire, sudan and uganda. The first evd outbreak was reported in the 1970s in zaire now the democratic republic of the congo. Detailed information about the ebola virus and the epidemiology of evd can be found in a first update, entitled outbreak of ebola virus disease in west africa, published on 8 april 2014. Zaire ebolavirus is the deadliest strain with sudan second, and also the one that is causing the current outbreak. As of september 14, 2014, a total of 4507 confirmed and probable cases of ebola virus disease evd, as well as 2296 deaths from the virus, had been reported from five countries in west africa.
Exacerbation of the disease may occur in the coming months because the topic is very important, i decided to refresh some information about this deadly disease. Both patients have been released from the hospital after testing confirmed that they no longer have ebola virus in their blood. Documented human and nonhuman primate outbreaks in africa ebola viruses constitute a serious threat to both human and wildlife health in the congo and. The reemergence of the same virus that hadnt been seen since the 1970s, and the fact that the virus was almost virtually the same, has scientists concerned by the durability and resilience of the virus. The 20142016 ebola outbreak in west africa has ended. As of june 18, 2014, a total of 528 cases, including 337 deaths, had been reported from guinea, liberia, and sierra leone.
Zaire ebolavirus, the most fatal ebola virus, was associated with the 20142016 outbreak in west africa, the largest ebola outbreak to date with more than 28,600 cases. The zaire strain was first detected in the congo drc in 1976. Center for emerging and zoonotic diseases, national institute for. However, a milder strain has been found in both pigs and monkeys in the philippines. The tremendous outbreak of ebola virus disease occurring in west africa since the end of 20 surprises by its remoteness from previous epidemics and dramatic extent.
This list of ebola outbreaks records the known occurrences of ebola virus disease, a highly. Ebola virus disease, which shows that the historical fatality of the zaire. According to the inventors, crossprotection studies will need to be done. Outbreak of ebola virus disease in west africa, fourth update, 3 sep 2014. The 2014 ebola outbreak in western africa has been the most severe. To reduce the risk of infecti on in west africa the following options are available. Both patients have been released from the hospital after testing confirmed that they no longer have ebola virus in. The 202016 outbreak, caused by ebola virus ebov 37 was the first anywhere in the world to reach epidemic proportions.
This contradicts professor francis boyles claim that the ebola virus in west africa transmitted by air. The outbreak started in guinea and rapidly spread to liberia and sierra leone, claiming thousands of lives. The recent ebola virus outbreak is in west africa, and is centered in parts of guinea and liberia. Socioeconomic impact of ebola virus disease in west. In the final stages of the disease, patients start leaking blood from every orifice and eventually bleed to death. Ebola haemorrhagic fever in gabon 1994, 1996, 1997 and 20012002. Analysis of the short and mediumterm costs of the ebola epidemic should spur governments of nonaffected countries to act quickly to put in place preventive measures. The ebola virus can cause severe viral haemorrhagic fever ebola hf outbreaks in. Number of new cases of ebola virus disease reported west africa, august 31september 20, 2014 cumulative number of reported ebola virus disease cases per 100,000 persons since december 22, 20. Several countries spanning the equatorial forest regions of africa have had outbreaks of ebola hemorrhagic fever over the last three decades. The virus is native to the continent of africa, where occasional outbreaks have occurred for years. Zaire, sudan and bundibugyo ebola viruses are accountable for most of the ehf epidemic but zebov establish a particularly serious threat to both human and nhps in subsaharan africa.
Ebola virus disease in west africa the first 9 months of. Pdf ebola virus disease evd is a lifethreatening viral disease with a fatality rate. Tracking virus outbreaks in the twentyfirst century nature. Ebola returns, and central africas virus hunters are ready. Pdf over the past 40 years, sporadic ebola virus disease evd outbreaks have occurred mostly in the central african region. The ebola virus disease outbreak now ravaging parts of west africa is the largest on record.
Unfortunately, many lessons learned from nearly four decades of ebola outbreaks in central africa did not inform the response when the virus emerged in guinea in 20. West africa, in guinea, and it spread rapidly to neighboring countries. The ebola virus can cause severe viral haemorrhagic fever ebola hf outbreaks in humans with a case fatality rate of up to 90%. In march 2014, the world health organization who reported a major ebola outbreak in guinea, a western african nation, the disease then rapidly spread to the neighboring countries of liberia and sierra leone with smaller outbreaks occurring in senegal, nigeria, and mali.
Ebola virus disease cumulative incidence west africa, september 20, 2014 boffa boke fria gaoual koundara conakry. Estimating the reproduction number of ebola virus ebov. A year after the deadliest ebola outbreak ever in africa, the virus has returned. 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. Because ebola virus is spread mainly through contact with the body fluids of symptomatic patients, transmission can be stopped by a combination of early diagnosis, contact tracing, patient isolation and care, infection control, and safe burial. Because it has spread to urban areas, it is different from earlier outbreaks, which were usually. Location of cases of ebola viral disease west africa, 2014 cases reported as of june 18, 2014. The latest 2014 breakout started in west africa, first cases notified in march 2014, is the largest and most complex ebola outbreak since the. She was the division head of microbiology at henry ford hospital in detroit, mi, for 12 years prior to joining the faculty at. Department statistics, karnatak university, dharwad, india abstract. Ebolavirus disease ebola outbreaks in africa important information for clinicians in secondary or tertiary care 6 june 2018 key point clinicians should be alert to the possibility of ebola in unwell travellers returning from affected areas of africa, and obtain a full travel and exposure history. The emergence of ebola as a global health security.
As of 20 february 2020 the outbreak is still ongoing. Ebola virus disease commonly known as ebola was first described in 1976 in two simultaneous outbreaks in the democratic republic of the congo and what is now south sudan. In 1976, the investigation of concurrent outbreaks of a hemorrhagic fever syndrome ebola virus disease evd in zaire currently democratic republic of congo and sudan currently republic of south sudan 1,2 led to isolation of 2 viruses now referred to as ebola virus ebov and sudan virus, respectively, and to identification of a newly recognized viral hemorrhagic fever genus. Oct 11, 2015 ebola virus disease evd started as a minor infection in uganda in 1974 and has been frequent in central africa region for the past 40 years. Ebola virus disease who regional office for africa. Biology 101, mwf 10am ebola paper ebola virus over the past couple years, discussion regarding the ebola virus has gone viral and ignited chaos both domestically and abroad. Dec, 2018 for example, the reebov antigen rapid test for ebola virus infection developed during the recent epidemic could be deployed throughout subsaharan africa to help detect new outbreaks 99,100. Distribution of ebola virus disease prevalence probability for west africa countries. In fact, west africa has seen more cases of the disease in 2014 than have been seen in all other. Ebola is a hemorrhagic fever that kills most of its victims within a few days.
Rapid risk assessment outbreak of ebola virus disease in west africa, seventh update, 17 oct 2014 2 the options for risk reduction are. Infected animals can transmit the virus to humans that are in any health condition. The 2014 epidemic got as bad as it did in part because west africa had no real experience with ebola, and in part because the disease spread from rural areas to citiesin guinea, liberia, and. Ebola virus disease outbreak west africa, september 2014. Analysis of ebola epidemic outbreaks in west africa talawar a.
At present, there is still no registered prophylaxis or curative biologicals against evd. The 2014 ebola virus ebov outbreak in west africa is the largest outbreak of the genus ebolavirusto date. It provides an update on research on the ecology of ebola viruses, modes of contamination and human transmission of the. For example, the reebov antigen rapid test for ebola virus infection developed during the recent epidemic could be deployed throughout subsaharan africa to help detect new outbreaks 99,100. That result meant that the volunteer had survived an encounter with that virus in the past. For over 40 years, ebola was treated as an african disease, called a fever and known by other names where occurrences have been frequent. Tracking virus outbreaks in the twentyfirst century. By combining classic field investigations with an assay that can measure ebola virus. As noted in a recent report from the who, ebola in west africa was an old disease in a new context that favored rapid and initially invisible spread who, 2015d.
The world health organization who announced saturday that an outbreak of ebola in the far north of the country. Rapid risk assessment outbreak of ebola virus disease in west africa, 8 april 2014 3 haemorrhagic manifestations can appear in more than half of the patients bloody diarrhoea, nosebleeds, haematemesis, petechiae, ecchymosis and puncture bleedings. Aug 01, 2014 haemorrhagic fever in guinea, dated 23 march 2014 12. The outbreak led to the discovery of a new species of ebola virus, namely ciebov le guenno et al. Socioeconomic impact of ebola virus disease in west african. Past and present article pdf available in the onderstepoort journal of veterinary research 792. According to the world health organization, ebola has been blamed for 11,310 deaths in the west africa nations of liberia, guinea and sierra leone, out of a total 28,616 cases. Zaire ebolavirus, bundibugyo ebolavirus, and sudan ebolavirus are the three species of ebola virus responsible for the larger outbreaks in africa. Ebola virus disease formerly known as ebola haemorrhagic fever is a severe, often fatal illness, with a death rate of up to 90% caused by ebola virus, a member of the filovirus family. The first outbreaks of ehf occurred nearly simultaneously in 1976 in the democratic republic of the congo drc, former zaire and sudan with very high case fatality rates of 88% and 53%, respectively. Between 1994 and 1996, outbreaks of ebolazaire occurred in parts of south africa, gabon, and the congo. Ebola virus disease in west africa no early end to the. West african ebola virus epidemic timeline of reported cases. A table of all known ebola outbreaks can be found in the who report who.
Number of cases of ebola viral disease n 398, by week of symptom onset guinea, 2014 cases reported as of june 18, 2014. E1e8 june 2012 with 366 reads how we measure reads. Ebola virus disease, which shows that the historical fatality of the zaire strain has been between 44% and above 90%. The genesis of the ebola virus outbreak in west africa the lancet. While public health interventions have been introduced in all affected countries, the numbers. Ebola virus disease evd started as a minor infection in uganda in 1974 and has been frequent in central africa region for the past 40 years. Ebola virus disease evd is a lifethreatening viral disease with a fatality rate ranging from around 30% to 90%. As of august 27, no confirmed ebola cases have been reported in the united states. Oct 16, 2014 because ebola virus is spread mainly through contact with the body fluids of symptomatic patients, transmission can be stopped by a combination of early diagnosis, contact tracing, patient isolation and care, infection control, and safe burial. The 2014 ebola virus disease evd outbreak in west africa is the longest, largest, deadliest, and the most complex in history. Analysis of ebola epidemic outbreaks in west africa.
On 11 june 2019, the who confirmed that a fiveyearold boy in uganda died after being diagnosed with ebola. Ebola virus disease in west africa pubmed central pmc. Genetic and epidemiological evidence from who officially confirms that the outbreak of ebola virus disease in the democratic republic of congo is unrelated to that ravaging west africa. The west african countries of guinea, liberia, and sierra leone have been. In march 2014, the ministry of health of guinea notified the world health organization of an ebola virus disease outbreak in the southeastern part of the country. The outbreak started in guinea and rapidly spread to liberia. Ebola in west africa cdcs role in epidemic detection. Jan 14, 2016 deadly ebola outbreak ends in west africa for now. Over the past 40 years, sporadic ebola virus disease evd outbreaks have occurred mostly in the central african region. Therefore, the patent was for the invention of a diagnosticmethod for detecting the bundibugyo strain of the ebola virus.