Here is some basic information about Ebola, a virus with a high mortality rate that was first identified in Africa in 1976.
Hemorrhagic fever of Ebola is a disease caused by one of the five different Ebola viruses. Four of the strains can cause serious diseases in humans and animals. The fifth virus, Reston, has caused disease in some animals, but not in humans.
The first human outbreaks occurred in 1976, one in northern Zaire (now Democratic Republic of Congo) in central Africa: and the other in southern Sudan (now South Sudan). The virus receives the name of the Ebola river, where the virus was first recognized in 1976, according to the Centers for Disease Control and Prevention (CDC).
Ebola is extremely infectious but not very contagious. It is infectious, because an infinitesimally small amount can cause an illness. Laboratory experiments on non-human primates indicate that even a single virus may be sufficient to cause a fatal infection.
Ebola can be considered moderately infectious because the virus is not transmitted through the air.
Humans can be infected by other humans coming into contact with body fluids of an infected person or contaminated objects from infected people. Humans can also be exposed to the virus, for example, biting infected animals.
While the exact reservoir of Ebola virus is still unknown, researchers believe that the most likely natural hosts are fruit sweet potatoes.
Ebola symptoms usually include: weakness, fever, pains, diarrhea, vomiting, and stomach pain. Additional experiences include skin rashes, red eyes, chest pain, sore throat, difficulty breathing or swallowing and bleeding (including the inner).
Normally, the symptoms appear between eight and 10 days after exposure to the virus, but the incubation period can last between two and 21 days.
Unprotected health workers are susceptible to infection due to their close contact with patients during treatment.
Ebola is not transmitted if someone is asymptomatic and usually not after someone has recovered. However, the virus was found in semen for up to three months and "possibly" is transmitted from contact with that son, according to the CDC.
Dead human epidemics have been confirmed in the following countries: Democratic Republic of the Congo (DRC), Gabon, South Sudan, Ivory Coast, Uganda, Republic of the Congo (ROC), Guinea, Liberia and Sierra Leone.
There are five subspecies of Ebola virus: Zaire ebolavirus (EBOV), Bundibugyo ebolavirus (BDBV), Sudan ebolavirus (SUDV), Taï forest ebolavirus (TAFV) and Restob ebolavirus (RESTV).
Click here for the CDC list of known cases and outbreaks.
2014-2016 Outbreak of West Africa:
(Complete historical chronology at the bottom)
March 25, 2014 – The CDC issues its initial announcement on an outbreak in Guinea and reports cases in Liberia and Sierra Leone. "In Guinea, a total of 86 suspected cases, including 59 deaths (mortality ratio per case: 68.5%), were reported as of March 24, 2014. Preliminary results of the Pasteur Institute in Lyon, France suggest that Zaire esbolavirus as a causative agent.
April 16, 2014 – The New England Journal of Medicine publishes a report, speculating that the current Zero patient was two years of age in Guinea. The son died on December 6, 2013, followed by his mother, sister and grandmother during the next month.
July 2014 – Patrick Sawyer, a senior government official at the Ministry of Finance in Liberia, dies in a local Nigerian hospital. He is the first American to die in which officers call the "deadliest Ebola outbreak in history."
July 2014 – Nancy Writebol, a US aid worker in Liberia, has tested positive for Ebola. According to the purse of Samaritan, Writebol infects when treating patients of Ebola in Liberia.
July 26, 2014 – Kent Brantly, medical director of the Ebola Consolidated Case Management Center of Samaritan Purse in Liberia, is infected with the virus. According to the bag of Samaritan, Brantly infects when treating patients with Ebola.
July 29, 2014 – According to Doctors Without Borders, Dr. Sheik Humarr Khan, who controlled the Ebola treatment at the Kenema Government Hospital in Sierra Leone, died of complications from the disease.
July 30, 2014 – The Peace Corps announces that it is eliminating its volunteers from Liberia, Sierra Leone and Guinea.
July 31, 2014 – The CDC raises its warning to Level 3. It warns the residents of the United States to avoid "non-essential trips" to Sierra Leone, Guinea and Liberia.
August 2, 2014 – A specially equipped medical airplane that takes the patient from Ebola. Dr. Brantly landed at the Dobbins air reservation base in Marietta, Georgia. Soon he is led by ambulance to Emory University Hospital in Atlanta.
August 4, 2014 – CNN reports that three more secret and experimental means of drug, "ZMapp", were taken to Liberia last week in a last effort to save Brantly and Writebol, according to a source familiar with the treatment details. Doctors report "significant improvement."
August 6, 2014 – Writebol arrives at Emory in Atlanta for treatment.
August 8, 2014 – World Health Organization experts (WHO) declare that the Ebola epidemic destroys West Africa an international health emergency that requires a coordinated global approach, describing it as the worst outbreak in the history of four decades of disease monitoring.
August 19, 2014 – The president of Liberia, Ellen Johnson Sirleaf, declares a curfew on the national level as of August 20 and orders that two communities be completely quarantined, without movement inside or outside the areas.
August 21, 2014 – Brantly is released from Emory University Hospital. It is also announced that Writebol was released on August 19. The releases come after Emory's staff relied on Brantly and Writebol to pose "no threat to public health."
September 6, 2014 – The government of Sierra Leone announces plans for a national blockade from September 19-21 to stop the spread of Ebola. The blockade is being considered as a predominantly social and non-medical campaign, in which volunteers go from time to time to talk to people.
September 16, 2014 – US President Barack Obama calls for efforts to fight the Ebola outbreak centered on West Africa, "the largest international response in the history of the CDC." While talking about the headquarters of the CDC in Atlanta, Obama adds that "before this outbreak, the world is looking at" the United States conducting international efforts to fight the virus. He says the United States is ready to take on this leadership role.
September 30, 2014 – Dr. Thomas Frieden, director of the CDC, announces the first diagnosed case of Ebola in the United States. The person was hospitalized and isolated at Texas Presbyterian Hospital Hospital in Dallas from September 28.
October 1, 2014 – The Liberian government officials release the name of the first case diagnosed with Ebola in the United States: Thomas Eric Duncan.
October 6, 2014 – A nurse assistant in Spain becomes the first person who has known how to get Ebola out of Africa in the current outbreak. The woman helped treat two Spanish missionaries, both of whom had taken Ebola in West Africa, one in Liberia and the other in Sierra Leone. Both died after returning to Spain. On October 19, the Special Committee of Ebola of Spain says that the nurse Teresa Romero Ramos considers herself free of the Ebola virus.
October 6, 2014 – NBC's independent cameraman, Ashoka Mukpo, arrives at the Nebraska Medical Center to receive treatment after getting Ebola in Liberia. On October 21, the hospital says that Mukpo no longer has the Ebola virus in the blood and will allow it to leave.
October 8, 2014 – Duncan dies of Ebola in Dallas.
October 11, 2014 – Nina Pham, a Dallas nurse who took care of the already disappeared Duncan of Ebola, shows positive for Ebola during a preliminary blood test. She is the first person to get Ebola on American soil.
October 15, 2014 – Amber Vinson, a Dallas nurse who also cared for Duncan, is diagnosed with Ebola. Authorities say that Vinson flew in a commercial jet from Cleveland to Dallas days before testing positive for Ebola.
October 20, 2014 – Under the fire following Ebola cases that include two Dallas nurses, the CDC updates Ebola guidelines that emphasize the importance of further training and supervision and recommends that the skin is not exposed when workers use personal protection equipment or PPE.
October 23, 2014 – Craig Spencer, a 33-year-old doctor who recently returned from Guinea, showed positive for Ebola – the first case of the New York City virus and the fourth diagnosed in the United States.
October 24, 2014 – The National Institutes of Health announce that one of the Dallas nurses, Pham, has been declared free of the Ebola virus. The doctors at Emory University Hospital said the tests no longer detect the virus in the blood of another nurse, Vinson. Pham is released from a Maryland hospital on October 24 and Vinson is released from a hospital in Atlanta on October 28.
October 24, 2014 – In response to the Ebola case in New York, the governors of New York and New Jersey announce that their states were intensifying the airport's selection beyond the federal requirements for travelers in West Africa. The new protocol requires a quarantine for any individual, including medical personnel, who had direct contact with individuals infected with Ebola while in Liberia, Sierra Leone or Guinea. The policy allows states to determine hospitalization or quarantine for up to 21 days for other travelers in affected countries.
November 5, 2014 – The nurse's assistant, Romero, who is considered the first person to get Ebola out of Africa, is released from the hospital in Madrid.
November 11, 2014 – Dr. Spencer, the first person in positive tests for Ebola in the city of New York, is released from the Bellevue hospital. With Spencer free of the virus, all patients in the US recovered. UU. They had Ebola.
November 15, 2014 – Dr. Martin Salia, who was infected with Ebola during the treatment of patients in Sierra Leone, arrives at the Nebraska Medical Center in Omaha. Salia, a native of Sierra Leone, is a legal resident of the United States married to an American citizen.
November 17, 2014 – Dr. Salia dies in the Medical Center of Nebraska.
December 24, 2014 – The CDC announces that a technician will be monitored for three weeks after it may be exposed to the Ebola virus at one of the agency's Atlanta labs. The agency reports a small amount of material that may contain content that the live virus was transferred by mistake from one laboratory to another.
December 2014 – The American doctor, Ian Crozier, who had been declared free of Ebola and released from Emory University Hospital in October 2014, finds the virus in his left eye. He had the disease while working in Sierra Leone. There is no risk of spreading the disease, Dr. Crozier is treated and on his way to Liberia in early April 2015.
January 18, 2015 – Mali is declared without Ebola without new cases in 42 days.
February 22, 2015 – Liberia reopens its land crossings closed during the Ebola outbreak and the president of Liberia, Sirleaf, also raises a national curfew imposed in August to help fight the virus.
May 9, 2015 – WHO declares the end of the Ebola outbreak in Liberia. More than 4,000 died.
November 2015 – The Ministry of Health of Liberia responds that three new confirmed cases of Ebola have sprouted in the country.
December 29, 2015 – WHO declares that Guinea is free of Ebola after spending 42 days since the last person confirmed that the virus was tested negative for the second time.
January 14, 2016 – The UN publishes a statement stating that "for the first time since the devastating outbreak began, all known Ebola transmission chains in West Africa have been detained and no new cases have been reported since the end of November."
January 15, 2016 – A new case of Ebola in Sierra Leone, in which the patient died, is confirmed by WHO and CDC.
March 29, 2016 – The WHO Director General raises the international public health emergencies (PHEIC) related to the Ebola outbreak 2014/2016 in West Africa.
* Includes information about Ebola and other outbreaks that give rise to more than 100 deaths or special cases.
1976 – The first recognition of EBOV's disease is in Zaire (now Democratic Republic of the Congo). The outbreak has 318 reported human cases, leading to 280 deaths. An outbreak of SUDV also occurs in Sudan (now Sudan of the South), which incurs 284 cases and 151 deaths.
1989 – In Reston, Virginia, imported monkeys from the Philippines are infected with the Ebola virus (later called the Ebola-Reston virus).
1990 – In Texas and Virginia quarantine facilities, four humans develop Ebola antibodies after contact with monkeys imported from the Philippines. None of the humans have symptoms.
1995 – An outbreak in the DRC (former Zaire) leads to 315 reported cases and at least 250 deaths.
2000-2001 – A Ugandan outbreak (SUDV) results in 425 human cases and 224 deaths.
2001-2002 – An EBOV outbreak occurs at the border of Gabon and the Republic of the Congo (ROC), which causes 53 deaths on the side of Gabon and at least 43 deaths on the side of the ROC.
December 2002 to April 2003 – An outbreak of EBOV in ROC results in 143 cases reported and 128 deaths.
2007 – An outbreak of EBOV occurs in the Democratic Republic of the Congo (DRC), 187 of the 264 cases reported result in death. At the end of 2007, an outbreak in Uganda leads to 37 deaths, with 149 cases reported in total.
November 2008 – The Ebola-Reston virus (RESTV) is detected in five humans in the Philippines. They are workers in a pig farm and a slaughterhouse and have no symptoms.
August 26, 2014-November 2014 – The Ministry of Health of the DRC informs the WHO about an Ebola outbreak in the country. It is the seventh outbreak in the country since 1976, when the virus was first identified near the Ebola river. The focus is not related to the ongoing outbreak in Guinea, Liberia, Nigeria and Sierra Leone. A total of 66 cases were reported, which causes 49 deaths.
July 31, 2015 – The CDC announces that a newly developed vaccine against Ebola is "highly effective" and can help prevent its spread in current and future outbreaks.
December 22, 2016 – The British medical journal, Lancet magazine publishes a story about a new Ebola vaccine that has proven 100% efficacy during drug trials. The study was conducted in Guinea with more than 11,000 people.
May 8, 2018 – The government of the DRC declares an outbreak of hemorrhagic fever of Ebola in the health zone of Bikoro. This is the ninth Ebola outbreak of DRC since the discovery of the virus in the country in 1976. The Ministry of Health in the DRC officially declared the outbreak on July 24, 2018. 54 cases of Ebola virus were recorded during the outbreak, including 33 deaths
August 1, 2018 – The DRC Ministry of Health declares an outbreak of Ebola virus in five health zones in the North Kivu province and a health zone in the Ituri province. The containment of the virus and the response can be difficult due to geographic and political challenges. As of November 4, a total of 300 people were infected, including 186 deaths. Of the 300 cases, 265 were confirmed by laboratory results, and 35 were likely.
August 27, 2018 – WHO reports that two of the first 16 people who received experimental therapy for Ebola recovered in the August 2018 outbreak in North Kivu and the Ituri provinces of the DRC. WHO spokesman Tarik Jasarevic said that five Ebola therapies were approved to treat people infected with the Ebola virus. Two are already in use and the other three will follow the example.
November 10, 2018 – The WHO reports that there are 205 deaths and 329 total cases in the DRC since August, becoming the worst outbreak of Ebola in the country's history. The neighboring country of Uganda is vaccinating its first-line health workers as a precautionary measure.