(Meredith / CNN) – The ongoing outbreak of Ebola in the Democratic Republic of Congo is "a crucial moment," the World Health Organization said on Friday.
Since the outbreak on August 1 has been declared, 116 people are infected, including 77 deaths. As of Wednesday, 86 of the cases were confirmed by laboratory results and 30 were likely.
But what is Ebola and why is it so deadly?
Ebola hemorrhagic fever 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, Reston virus, has caused disease in some animals, but not in humans.
There are five subspecies of the Ebola virus: Zaire Ebola virus (EBOV) Bundibugyo Ebola virus (BDBV) Sudan Ebola virus (SUDV) Taï Forest Ebola virus (TAFV) Reston Ebola virus (RESTV)
Infectious, but not very contagious
Ebola is extremely contagious, but not extremely contagious. It is contagious because an infinitesimal number of diseases can cause. Laboratory experiments on non-human primates suggest that even a single virus may be sufficient to cause a fatal infection.
Ebola can be considered as moderately contagious because the virus is not transmitted by air.
Humans can be infected by other people if they come into contact with body fluids from an infected person or infected objects from infected people. People can also be exposed to the virus, for example by slaughtering infected animals.
Although the exact reservoir of Ebola viruses is still unknown, researchers think that the most likely natural hosts are fruit bats.
What are the symptoms?
Symptoms of Ebola are usually: Weakness Fever Pears Diarrhea Vomiting Gastric pain Rash Red eye Chest pain Sore throat Difficulties with breathing Swallowing Haemorrhage (including internal) Symptoms seem to be eight to ten days after exposure to the virus, but the incubation period may be two to 21 days.
Unprotected healthcare workers are prone to infections because of their close contact with patients during treatment.
How do people get Ebola?
Ebola is not transferable if someone is asymptomatic and usually not after someone has recovered from it. However, the virus was found in sperm for up to three months and "possible" is transmitted by contact with that sperm, according to the CDC.
Deadly human Ebola outbreaks have been confirmed in the following countries: Democratic Republic of Congo (DRC) Gabon South Sudan Ivory Coast Uganda Republic of the Congo (ROC) Guinea Liberia Sierra Leone
Expansion West Africa 2014-2016:
March 25, 2014 – The CDC announces its first announcement about an outbreak in Guinea and reports of cases in Liberia and Sierra Leone. "In Guinea, a total of 86 suspect cases, including 59 deaths (case fatality ratio: 68.5%), were reported on 24 March 2014. Preliminary results from the Pasteur Institute in Lyon, France suggest that Zaire Ebola virus is the cause."
April 16, 2014 – The New England Journal of Medicine publishes a report speculating that the current outbreak Patient Zero was a two-year-old girl from Guinea. The child died on 6 December 2013, followed by his mother, sister and grandmother the following month.
July 2014 – Patrick Sawyer, a senior civil servant in the Liberian Ministry of Finance, dies in a local Nigerian hospital. He is the first American to die in what officials call the "deadliest Ebola outbreak in history".
July 2014 – Nancy Writebol, an American aid worker in Liberia, tests positive for Ebola. According to Samaritan & # 39; s Purse, Writebol is infected during the treatment of Ebola patients in Liberia.
July 26, 2014 – Kent Brantly, medical director of the Ebola Consolidated Case Management Center of Samaritan Purse, is infected with the virus. According to Samaritan's Purse, Brantly is infected during the treatment of Ebola patients.
July 29, 2014 – According to Médecins Sans Frontières, Dr. Sheik Humarr Khan who supervised the Ebola treatment at Kenema Government Hospital in Sierra Leone for complications of the disease.
July 30, 2014 – The Peace Corps announces that it will remove its volunteers from Liberia, Sierra Leone and Guinea.
July 31, 2014 – The CDC warns against level 3. It warns US residents to avoid "non-essential trips" to Sierra Leone, Guinea and Liberia.
August 2, 2014 – A specially equipped medical airplane with Ebola patient. Brantly lands at Dobbins Air Reserve Base in Marietta, Georgia. He is then taken to the Emory University Hospital in Atlanta by an ambulance.
August 4, 2014 – CNN reports that three top secret, experimental vials of the drug, "ZMapp," were flown in Liberia last week in a last attempt to save Brantly and Writebol, according to a source familiar with the details of the treatment. Doctors report "significant improvement".
August 6, 2014 – Writebol comes to Emory in Atlanta for treatment.
August 8, 2014 – World Health Organization (WHO) experts state that the Ebola West Africa epidemic is reaching an international health emergency that requires a coordinated global approach, and describes it as the worst outbreak in the four decades of disease tracking.
August 19, 2014 – Liberia's president Ellen Johnson Sirleaf declares a nationwide curfew from August 20 and recommends that two communities be completely quarantined without movement in or out of the areas.
August 21, 2014 – Brantly is discharged from Emory University Hospital. It is also announced that Writebol was released on August 19. The releases come after Emory's staff are convinced that Brantly and Writebol are "no threat to public health".
September 6, 2014 – The Sierra Leone government is announcing plans for a national lockdown on September 19-21 to stop the spread of Ebola. The lockdown is invoiced as a predominantly social campaign instead of a medical one, whereby volunteers go door-to-door to talk to people.
September 16, 2014 – US President Barack Obama calls the efforts to combat the outbreak of Ebola in West Africa "the biggest international reaction in the history of the CDC". From the headquarters of the CDC in Atlanta, Obama adds: "facing this outbreak, the world is looking to" the United States to make international efforts to fight the virus. He says the United States is ready to take that leading role.
September 30, 2014 – Dr. Thomas Frieden, director of the CDC, announces the first diagnosed case of Ebola in the United States. The person has been admitted to the Texas Health Presbyterian Hospital in Dallas since September 28.
1 October 2014 – Liberian government officials release the name from the first case of Ebola in the United States: Thomas Eric Duncan.
6 October 2014 – A nursing assistant in Spain becomes the first person known to have contracted Ebola outside of Africa during the current outbreak. The woman helped to treat two Spanish missionaries, who had both received Ebola in West Africa, one in Liberia and the other in Sierra Leone. Both died after returning to Spain. On 19 October, the Special Ebola Committee of Spain says that nurse Teresa Romero Ramos of the nurse is considered free of the Ebola virus.
6 October 2014 – NBC freelance cameraman Ashoka Mukpo arrives in Nebraska Medical Center for treatment after contracting Ebola in Liberia. On 21 October, the hospital says that Mukpo no longer has the Ebola virus in its bloodstream and is allowed to leave.
October 8, 2014 – Duncan dies of Ebola in Dallas.
October 11, 2014 – Nina Pham, a Dallas nurse who took care of the deceased Ebola patient Duncan, tests positive on Ebola during a preliminary blood test. She is the first person to contract Ebola on US soil.
October 15, 2014 – Amber Vinson, a second nurse in Dallas who also cares for Duncan, is diagnosed with Ebola. Authorities say Vinson flew on a commercial jet from Cleveland to Dallas before testing positive on ebola.
October 20, 2014 – Under fire after Ebola cases involving two nurses in Dallas, the CDC published updated Ebola guidelines that emphasize the importance of increased training and supervision, and recommends that no skin be exposed when workers wear personal protective equipment, or PBM & # 39; s.
October 23, 2014 – Craig Spencer, a 33-year-old physician who recently returned from Guinea, has tested positive for Ebola – the first case of the deadly virus in New York City and the fourth diagnosed in the United States.
October 24, 2014 – The National Institutes of Health announces one of the Dallas nurses, Pham, has been declared free of the Ebola virus. Doctors at Emory University Hospital say that tests no longer detect the virus in the blood of the other nurse, Vinson. Pham is released from a hospital in Maryland on October 24 and Vinson is released from a hospital in Atlanta on October 28.
October 24, 2014 – In response to the New York Ebola case, the New York and New Jersey governors announce that their states are intensifying screening at airports over federal requirements for travelers from West Africa. The new protocol requires a quarantine for each individual, including medical staff, who have had direct contact with people infected with Ebola in Liberia, Sierra Leone or Guinea. The policy allows states to determine hospitalization or quarantine for up to 21 days for other travelers from affected countries.
November 5, 2014 – Nurse & # 39; s assistant Romero, presumably the first person to contract Ebola outside Africa, is released from the hospital in Madrid, Spain.
November 11, 2014 – Dr. Spencer, the first person to test positive for Ebola in New York City, is released from the Bellevue Hospital. Now that Spencer is free of the virus, all American patients with Ebola have recovered.
November 15, 2014 – Dr. Martin Salia, who was infected with Ebola while treating patients in Sierra Leone, arrives at the Nebraska Medical Center in Omaha. Salia, born in Sierra Leone, is a legal resident of the United States, married to an American citizen.
November 17, 2014 – Dr. Salia dies at the Nebraska Medical Center.
December 24, 2014 – The CDC announces that a technician will be monitored for three weeks after he may have been exposed to the Ebola virus in one of the Atlanta laboratories of the agency. The agency reports that a small amount of material that possibly contained the live virus was accidentally transferred from one lab to another.
December 2014 – American doctor Ian Crozier, who had been declared exempt from Ebola and released from Emory University Hospital in October 2014, finds the virus in his left eye. He had contacted the disease during his work in Sierra Leone. With no risk of spreading the disease, Dr. Crozier treated in early April 2015 and on his way to Liberia.
January 18, 2015 – Mali is declared Ebola free after no new cases in 42 days.
February 22, 2015 – Liberia reopens its land border crossing during the Ebola outbreak and Liberian President Sirleaf also has a national curfew imposed in August to help fight the virus.
May 9, 2015 – WHO declares an end to the Ebola outbreak in Liberia. More than 4,000 died.
November 2015 – Liberia's health ministry says that three new, confirmed cases of Ebola have surfaced in the country.
December 29, 2015 – The WHO states that Guinea is free from Ebola after 42 days since the last person who confirmed that the virus was tested negative for the second time.
January 14, 2016 – A statement is released by the UN stating that "For the first time since this devastating outbreak has begun, all known transmission chains of Ebola in West Africa have stopped and no new cases have been reported since the end of November."
15 January 2016 – A new case of Ebola in Sierra Leone, in which the patient died, is confirmed by the WHO and CDC.
29 March 2016 – The WHO Director General raised the public health emergency situation with international concern (PHEIC) with regard to the Ebola outbreak of 2014-2016 in West Africa.
The following timeline contains information about Ebola and other outbreaks that result in more than 100 deaths or special cases.
1976 – First recognition of the EBOV disease is in Zaire (now the Democratic Republic of Congo). The outbreak has reported 318 cases in humans, leading to 280 deaths. A SUDV outbreak also takes place in Sudan (now South Sudan), which causes 284 cases and 151 deaths.
1989 – In Reston, Virginia, maca monkeys imported from the Philippines are infected with the Ebola virus (later called the Ebola-Reston virus).
1990 – In quarantine facilities in Texas and Virginia, four people develop Ebola antibodies after contact with monkeys imported from the Philippines. None of the people has 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 cases of people and 224 deaths.
2001-2002 – An EBOV outbreak takes place at the border with Gabon and the Republic of Congo (ROC), resulting in 53 deaths on the Gabon side and at least 43 deaths on the ROC side.
December 2002 – April 2003 – An EBOV outbreak in ROC results in 143 reported cases and 128 deaths.
2007 – An EBOV outbreak takes place in the Democratic Republic of the Congo (DRC), 187 of the 264 reported cases lead to death. At the end of 2007, an outbreak in Uganda led to 37 deaths, with a total of 149 cases.
November 2008 – The Ebola Reston virus (RESTV) is detected in five people in the Philippines. They are employees at a pig farm and a slaughterhouse and have no symptoms.
26 August 2014 – November 2014 – The Ministry of Health in the DRC warns the WHO against 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 outbreak is not related to the ongoing outbreak in Guinea, Liberia, Nigeria and Sierra Leone. A total of 66 cases were reported, resulting in 49 deaths.
July 31, 2015 – The CDC announces that a newly developed Ebola vaccine is "very effective" and could help prevent it from spreading in the current and future outbreaks.
December 22, 2016 – The British medical journal, The Lancet, publishes a story about a new Ebola vaccine that has been tested 100% effectively during trials of the drug. The study was conducted in Guinea with more than 11,000 people.
May 8, 2018 – The government of the Democratic Republic of Congo declares an outbreak of haemorrhagic fever from ebola in the Bikoro health zone. This is the ninth Ebola outbreak of the DRC since the discovery of the virus in the country in 1976. The Ministry of Health in the Democratic Republic of Congo officially declares the outbreak on July 24, 2018. Fifty-four cases of Ebola virus were recorded during the outbreak, including 33 deaths.
1 August 2018 – The DRC Ministry of Public Health declares an outbreak of the Ebola virus in five health zones in the province of North Kivu and a health zone in the province of Ituri. Combating the virus and the reaction can be difficult due to geographical and political challenges. As of August 6, a total of 43 cases have been reported, including 36 deaths.