Updated: Jun 12, 2020
The Ebola virus was first identified in 1976 in the village near the Ebola river in the Democratic Republic of the Congo, Africa. Since then there have been several outbreaks from time to time in African countries including the largest 2014-2016 Ebola outbreak in West Africa and the highly complex 2017-2020 Ebola outbreak in the Democratic Republic of the Congo that was declared a world health emergency in July 2019.
Scientists confirm that the Ebola virus had existed long before the first recorded outbreaks of 1976. Population growth, hunting wild animals and consuming their meat as well as encroachment into forested areas have contributed to the Ebola virus spread. Deforestation has been linked to the index cases of the Ebola virus disease meaning that those that first got infected with the Ebola virus lived in close proximity to the recently deforested lands.
There are 6 species within the genus Ebolavirus and 4 of those(Zaire, Sudan, Bundibugyo and Tai Forest) cause Ebola disease in people. It is currently unknown if the Bombali virus identified in bats is capable of causing Ebola in either humans or animals. Reston virus causes Ebola in pigs and nonhuman primates.
In the past outbreaks of Ebola virus the fatality rates varied 25-90%, however, the average Ebola virus disease mortality rate is around 50%.
There were 4 confirmed cases of Ebola in the USA in 2014, one dead, 25% mortality rate. One confirmed case of Ebola was reported in the UK and 1 in Spain in 2014. One confirmed case of Ebola was then reported in Italy in 2015.
Transmission and spread of Ebola
Humans usually get infected directly from fruit bats or from porcupines, forest antelope and non-human primates(chimpanzees, gorillas). The study dated February 2013 found that fruit bats in Bangladesh have antibodies against Zaire and Reston viruses. This suggests that filoviruses are present in Asia and that these bats are potential hosts of Ebola Virus.
Ebola virus is contracted through direct contact with the blood, body fluids and secretions (such as sweat, tears, saliva,vomit, urine, poo, breast milk and semen) and skin of an infected animal or human. An infected person with Ebola with no symptoms can’t spread the disease.
Some laboratory workers get infected with Ebola in the lab by accidently touching contaminated needles or incorrectly handling samples collected from infected animals or humans, which are an extreme biohazard risk. A Russian scientist died from Ebola in 2004 after contracting Ebola from the infected needle she was using in the experiments.
Touching the medical equipment used in the care of the infected person as well as touching contaminated surfaces and materials(clothing, bedding, etc.) of the infected animal or human is a risk factor of contracting Ebola virus.
Healthcare workers caring and treating those infected with Ebola are at a very high risk of contracting it. Lack of PPE (personal protective equipment), inadequate training on how to use it and incorrect disposal of infected clothing, bedding and objects increase the risk of Ebola virus contraction.
Burial ceremonies in the countries of Africa very often involve direct contract with the dead body for traditional rituals and this contributes to Ebola virus transmission.
Eating wild life meat which is uncooked or poorly cooked is a risk factor as well. In African countries the hunting and consumption of bats and monkeys that are reservoirs and hosts of Ebola virus is common. This contributes to Ebola outbreaks.
Another risk factor of contracting Ebola is having unprotected sex with someone who is infected with Ebola or has recently recovered from it. There is some research confirming that traces of Ebola virus are found in semen many months after recovery. Ebola survivors are recommended by the WHO to practice protected sex for 12 months from the onset of Ebola symptoms and until their semen tests negative twice for the Ebola virus.
Symptoms of Ebola
Symptoms of Ebola usually start 2 to 25 days after contracting it and can include:
Low white blood cell count
Low platelet count
Elevated liver enzymes
About 50% of the infected develop a skin rash(maculopapular rash looking like small bumps on the skin area affected) within 5 to 7 days from the onset of symptoms.
Ebola damages the immune system and internal organs causing internal and external bleeding due to the decline in the levels of blood-clotting cells. This bleeding usually occurs within 5 to 7 days after the initial symptoms. Blood can come out from eyes, ears, gums and nose.
Ebola survivors develop antibodies against Ebola that last at least 10 years but they often have joint and muscle pain, liver inflammation,decreased eyesight and hearing after their recovery.
Prevention of Ebola
Preventative methods for the Ebola virus include the following:
Do not eat the uncooked or poorly cooked meat of wild animals
Avoid touching dead animals and their raw meat
Wash fruit and veg thoroughly and peel them before consumption
Wash your hands with soap or use hand rubs with alcohol
Practice only safe sex, especially with those who have survived Ebola in the last 12 months
Treatment of Ebola
There is no proven treatment for Ebola. Ebola symptoms can be managed with supportive treatment meaning that treatments such as blood transfusions, fluids and electrolytes will be given to deal with the symptoms of Ebola while the body of the infected person fights the infection.
Dehydration is common in the infected patient with Ebola and fluids are given orally or intravenously(directly into a vein).
Due to the loss of fluids, the blood pressure goes down so blood oxygen levels and blood pressure are monitored and maintained at the right level to help the infected person to fight the infection.
In the current outbreak of Ebola in the Democratic Republic of the Congo an experimental Ebola vaccine rVSV-ZEBOV is being used. This vaccine was approved in December 2019 in the United States.
The vaccine is fully effective ten days after being administered and as of 2019 more than 100,000 people have been vaccinated against Ebola.
However, it is worth noting that the rVSV-ZEBOV vaccine is a vaccine protective against only the Zaire ebolavirus species of ebolavirus.
Ebola outbreaks since 1976
Ebola outbreak in Sudan in 1976
The first known outbreak of Ebola occurred between June and November 1976 in Nzara, South Sudan. The first infected person was identified in a Nzara cotton factory which was frequented by bats.
The Sudan outbreak of Ebola was caused by the Sudan strain of the Ebola virus and out of 284 infected with Ebola, 151 died.
Ebola outbreak in Zaire in 1976
On 26 August 1976, a second outbreak of the Ebola virus began in a small village in Northern Zaire (now it is the Democratic Republic of the Congo). The outbreak was caused by the Zaire ebolavirus in contrast to the Sudan outbreak that was caused by the Sudan ebolavirus.
The first infected person was a village’s school headmaster who had returned from a trip near the Ebola river. Those who were in contact with him also died.
One of the discoverers of Ebola was a Congolese scientist Jan-Jacques Muyembe-Tamfum. Despite having come in direct contact with the unknown disease he survived. The sample he collected was used by Peter Piot to identify the unknown Ebola virus. Piot concluded that Belgian nuns were giving unnecessary vitamin injections to pregnant women with unsterilised syringes and needles and this has spread the epidemic.
Ebola outbreaks between 1995–2016
The second Ebola outbreak occurred in Zaire in 1995, now the Democratic Republic of the Congo, with 315 infected, 254 dead.
In 2000 another Ebola outbreak in Uganda, 425 infected, 224 dead.
In 2003 in the Democratic Republic of the Congo, 143 infected, 128 dead as a result of Ebola outbreak.
In 2007 in the Democratic Republic of the Congo, 264 infected, 187 dead due to Ebola virus.
In November 2007 in Western Uganda another Ebola outbreak with 149 infected, 37 dead.
In 2012 in Uganda 2 outbreaks of Ebola virus were reported with 7 people infected and 4 dead in the first outbreak and 24 infected and 17 dead in the second outbreak.
In 2012 in the Democratic Republic of the Congo, 57 infected, 29 dead in the Ebola outbreak with a probable cause of bushmeat/wildlife meat consumption.
In 2014 in the Democratic Republic of the Congo, 66 infected, 49 dead in the Ebola outbreak.
2014-2016 Ebola outbreak in West Africa
The largest outbreak of Ebola was in West Africa that occurred from December 2013 to January 2016, with 28 646 infected and 11 323 dead.
The outbreak started in Guinea with an 18-month-old child who is believed to have been bitten by a bat and later died in December 2013 of the Ebola virus. The Ebola outbreak then moved to Sierra Leone and Liberia. It was the longest and the largest outbreak of Ebola since 1976 and the estimated cost of this epidemic is a total of $4.3 billion.
Despite the local and international efforts to contain this epidemic, the Ebola virus disease spread to Mali, Nigeria, Senegal and the United States as well as to Europe- Italy, Spain, the United Kingdom. Human-to-human transmission was later recorded, mainly in a healthcare setting, in the United States, Italy, Mali and Nigeria.
Approximately 20% of the Ebola cases in West Africa occurred in children under 15 years of age.
Healthcare workers were also vulnerable to Ebola virus during this outbreak because they work closely with the infected body fluids and they constituted 10% of the dead during the outbreak.
The Ebola epidemic in Liberia, Sierra Leone and Guinea impacted other healthcare services in terms of disruptions and delays that it caused in the treatment of HIV, malaria, TB and measles in these countries.
Further spread of Ebola was prevented due to the international aid, strict isolation policies and intense contact tracing.
2017-2020 Ebola outbreak in the Democratic Republic of the Congo
Consequent outbreaks of Ebola happened in the Democratic Republic of the Congo in May 2017 and 2018 and a world health emergency was declared in July 2019.
North Kivu is a province in the Democratic Republic of the Congo. The Ebola outbreak that started there on 1 August 2018 is the second largest Ebola outbreak with over 1 000 cases.
As of 3 May 2020, 3 317 confirmed cases and 2279 deaths have occurred as a result of this outbreak.
This Ebola outbreak is highly complex because it is the first Ebola outbreak in a military conflict zone with thousands of refugees in the area.
Has Ebola won despite having a vaccine against it?
The Ebola virus has been around since 1976 in Africa, and Ebola oubreaks have been recorded from time to time in different countries including the cases in the USA and Europe that were brought in to those countries by travellers from Africa.
The rVSV-ZEBOV vaccine is a vaccine protective against only the Zaire ebolavirus species of ebolavirus and not against other species of ebolavirus.
Deforestation in Africa leaves bats and other wildlife species that are reservoirs of Ebola virus without their natural habitats. It pushes them to live in close proximity to human populations and therefore subject humans to all sorts of viruses and diseases.
Human encroachment on wildlife in different ways such as hunting wildlife and continued desctruction of forests cannot go unnoticed and unpunished by nature. We are interfering in the nature's domain disturbing its species and their habitats.
And until such devastating and extensive human encroachment on wildlife is limited or halted, neither prevention nor vaccine will save us.