Ebola virus disease: The phrase “Ebola disease” refers to a group of four ebolaviruses that belong to the genus Ebolavirus that cause fatal diseases in humans. There are sporadic human epidemics of the Ebola virus, which mostly affects people in Africa.
In humans, the Ebola virus disease (EVD or Ebola) is a rare but serious condition. Often, it ends in death.
By touching, people can contract the Ebola virus:
- infected animals when handling, cooking, or eating them
- bodily fluids from an infected person, such as saliva, urine, faeces, or semen
- articles of clothing or bedding that have been in contact with bodily fluids from an infected person
Cuts in the skin or touching the eyes, nose, or mouth allow Ebola to enter the body.
Fever, exhaustion, and headache are some of the early symptoms.
Vaccines and medications can be used to treat some kinds of Ebola.
Two outbreaks of Ebola occurred at the same time in 1976, one in Yambuku, Democratic Republic of the Congo, and the other in what is now Nzara, South Sudan. The latter incident occurred in a neighbourhood near the Ebola River, which lends the illness its name.
Cuevavirus, Marburgvirus, and Ebolavirus are the three genera that make up the virus family Filoviridae. Six species of Ebolavirus have been identified, including those from Zaire, Bundibugyo, Sudan, Ta Forest, Reston, and Bombali.
Transmission of Ebola virus disease
The Pteropodidae family of fruit bats is hypothesised to act as a natural host for the Ebola virus. Humans can contract the disease from infected animals such as fruit bats, chimpanzees, gorillas, monkeys, forest antelope, or porcupines discovered sick, dead, or in the rainforest if they come into close contact with their blood, secretions, organs, or other bodily fluids.
Then, Ebola transmits from person to person by direct touch (through punctured skin or mucous membranes) with:
- blood or bodily fluids from an individual who has Ebola or has passed away from it; and
- things that have been contaminated by bodily fluids (such as blood, faeces, or vomit) from an Ebola patient or the body of an Ebola victim.
While caring for patients who had Ebola, whether suspected or confirmed, healthcare personnel regularly become infected. Close contact with patients when infection control procedures are not carefully followed results in this.
Ebola can also spread during funeral rites as attendees come into close contact with the deceased’s body.
As long as the virus is present in a person’s blood, they are contagious. Sexual transmission after recovery is a possibility, although it can be minimised with care and education for survivors.
It’s possible for pregnant women who contract acute Ebola and recover from the illness to continue harbour the virus in their breastmilk or in tissues and fluids associated to pregnancy.
The signs of the Ebola virus, which include fever, lethargicness, soreness in the muscles, headaches, and sore throats, might emerge abruptly. Vomiting, diarrhoea, a rash, and internal and external bleeding accompany these.
From the moment of infection until the onset of symptoms, it typically takes 2 to 21 days. Once an individual has signs of Ebola, they can no longer transmit the illness. Even after they have passed away, a person can still spread the Ebola virus as long as it is still in their body.
Some people may experience symptoms for up to two years after Ebola recovery. These signs may consist of:
- feeling tired
- muscle and joint pain
- eye pain and vision problems
- weight gain
- belly pain and loss of appetite
- hair loss and skin problems
- trouble sleeping
- memory loss
- hearing loss
- depression and anxiety.
People should consult a medical expert if they have:
- symptoms, been in a region where Ebola is known to exist, or
- had contact with a potential Ebola patient.
Clinically separating the Ebola virus disease from other infectious illnesses such malaria, typhoid fever, and meningitis can be challenging. Pregnancy symptoms and those of the Ebola virus are very similar in many ways. If Ebola is suspected, pregnant women should ideally be tested as soon as possible due to hazards to the pregnancy and to the women themselves.
These diagnostic techniques are used to confirm that symptoms are brought on by Ebola virus infection.
- antibody-capture enzyme-linked immunosorbent assay (ELISA)
- antigen-capture detection tests
- serum neutralization test
- reverse transcriptase polymerase chain reaction (RT-PCR) assay
- electron microscopy
- virus isolation by cell culture
Prevention and Vaccine (Ebola virus disease)
Ebolaviruses are thought to spread slowly among some animal groups in the regions where the disease is most prevalent. When a person comes into contact with an infected animal, the ebolavirus can be transmitted to them. Once infected, an individual can contract the Ebola virus, become ill, and infect those who come into contact with them.
There are a number of measures to safeguard oneself and stop the spread of the Ebola virus when residing in or visiting a place where ebolaviruses may be present.
- Avoid coming into contact with ill people’s blood and bodily fluids, including their urine, faeces, saliva, sweat, vomit, breast milk, amniotic fluid, semen, and vaginal secretions.
- Even if a man has recovered from Ebola, you shouldn’t touch his sperm until tests show that the virus is gone.
- Avoid touching any items that may have come into contact with an infected person’s blood or body fluids, including bedding, clothing, needles, and medical supplies.
- Avoid handling a body that has been identified as having Ebola illness during funeral or burial procedures.
- The blood, fluids, or raw meat produced from bats, woodland antelopes, non-human primates (such as monkeys and chimpanzees), and unknown creatures should all be avoided.
The same precautions should be taken if you live in or visit a place where there is an Ebola outbreak. People should keep an eye on their health for 21 days after leaving an Ebola-affected area, and seek medical attention right once if any Ebola symptoms appear.
On December 19, 2019, the American Food and Drug Administration (FDA) authorised the rVSV-ZEBOV Ebola vaccine, also known as Ervebo®. The sole type of the Zaire ebolavirus, which has been linked to the deadliest and largest Ebola outbreaks to date, has been demonstrated to be safe and effective against this vaccine, which is given as a single dose. This is the first ebolavirus vaccine that the FDA has approved.
For persons over the age of 18 in the US population who may be at risk of occupational exposure to the Zaire ebolavirus, the Advisory Committee on Immunisation Practises (ACIP) advised pre-exposure prophylactic vaccination with rVSV-ZEBOV on February 26, 2020. This suggestion applies to adults who are
- Healthcare workers working at federally designated Ebola Treatment Centres;
- Laboratorians or other staff working in biosafety-level 4 facilities that work with live Ebola virus in the United States; or
- Planning or executing an Ebola virus epidemic response within the USA
Visit Ebola Vaccine: Information on Ervebo® if you’re a healthcare provider looking for details on the Ebola vaccine and immunising ACIP-recommended groups.
In 2019, during an Ebola outbreak in the Democratic Republic of the Congo, a two-dose vaccination regimen of a separate vaccine that was also intended to provide protection against the Zaire ebolavirus species of Ebola was employed as part of a research protocol. The two doses of this regimen, which asks for an initial dosage and a “booster” injection 56 days later, use different vaccine components called Ad26.ZEBOV and MVA-BN-Filo. The FDA has not yet approved this immunisation for normal use.
Contact with the blood or bodily fluids of an infected individual is how Ebolaviruses spread. Broken skin or mucous membranes in the eyes, nose, or mouth are two entry points for them into the body. By contacting one’s face with contaminated hands, this is a simple possibility. An essential part of personal and community hygiene, hand hygiene (including the use of alcohol-based hand rubs, soap and water, and appropriate glove use) is a key strategy to stop the transmission of illnesses while providing healthcare. Correct hand washing reduces the amount of germs on the hands and reduces the chance that harmful bacteria, like ebolaviruses, may spread.
The following is a description of good hand hygiene practises. In most clinical settings, using alcohol-based hand sanitizers is the recommended technique for washing your hands. Wash hands with soap and water if they are visibly stained with blood or other bodily fluids.
- When hands are not obviously dirty, use an alcohol-based hand sanitizer. Typically, these goods have an ethanol or isopropanol content of 60–95%. When hands are clearly stained with dirt, blood, or other bodily fluids, alcohol-based hand sanitizer shouldn’t be applied.
- When hands are obviously stained with grime, blood, or other bodily fluids, wash them with soap and water rather than an alcohol-based hand sanitizer. It has not been established that antimicrobial soaps are superior than washing hands with water and regular soap.
- When soap and hand sanitizer are not available, use a moderate (0.05%) chlorine solution. The use of 0.05% chlorine solution repeatedly can irritate the skin.
The U.S. Food and Drug Administration (FDA) has currently approved two treatments* to treat EVD in both adults and children brought on by the Zaire ebolavirus, a type of the Ebola virus. InmazebTM, a mixture of three monoclonal antibodies, is the first medication to be authorised in October 2020. A single monoclonal antibody called EbangaTM, the second medication, received approval in December 2020. Monoclonal antibodies, often known as mAbs, are synthetic proteins that work similarly to natural antibodies to stop a pathogen, such as a virus, from proliferating after it has infected a human. They are produced in laboratories or other production facilities. These particular mAbs bind to the glycoprotein, a surface-bound element of the Ebola virus that prevents the virus from entering host cells.
During the Ebola outbreak in the Democratic Republic of the Congo in 2018–2020, a randomised controlled study was carried out to evaluate both of these medications as well as two others. Both of the two FDA-approved medicines dramatically increased the overall survival rate for patients. It has not been investigated whether InmazebTM and EbangaTM are effective against ebolaviruses other than the Zaire variety.
Basic interventions, when given early, can dramatically increase odds of survival whether or not there are other treatments available. These are categorised as supportive care and consist of:
- the intravenous or oral infusion of water and electrolytes (body salts).
- Taking medication to stabilise blood pressure, lessen nausea and vomiting, control fever, and ease pain.
- treating further infections, if any arise.
The two largest Ebola outbreaks to date, West Africa in 2014 and the Democratic Republic of the Congo in 2018, have left behind more Ebola survivors than ever before. With so many survivors, it is possible to learn more about how ebolaviruses affect those who have recovered and to provide survivors advice on how to look after themselves and their communities.
Recovery from Ebola
Effective supportive treatment and the patient’s immune response are key components of recovery from Ebola sickness. The overall survival rate is also rising because to experimental therapies.
Those who do recover produce antibodies that may persist up to 10 years. The ebolavirus species that affected the survivors is likely to have rendered them somewhat immune to it. It is unknown if those who recover have a lifelong immunity to the disease or if they can subsequently contract a new species of the ebola virus. Some survivors may experience long-term effects, such as joint and eye problems.
Health Concerns for Survivors of Ebola
People who have fully recovered from the Ebola virus typically do not contract it again. However, many Ebola survivors experience health problems even after they have recovered.
The complications that are most frequently reported include:
- Muscle and joint pain
- issues with the eyes and eyesight (blurred vision, discomfort, redness, and light sensitivity)
- Weight gain
- Stomach pain or loss of appetite
Memory loss, neck swelling, dry mouth, tightness in the chest, hair loss, hearing issues (ringing in the ears and hearing loss), pain or tingling in the hands or feet, inflammation of the pericardium (tissue around the heart), inflammation of one or both testicles, changes in menstruation, impotence, decreased or lost interest in sex, difficulty falling or staying asleep, depression, anxiety, and post-traumatic stress disorder are some additional health issues that can occur.
When complications begin, how severe they are, and how long they last in Ebola illness survivors can vary.
After an acute infection, ebolaviruses can persist in the body’s immunologically privileged locations. Even after being eliminated from other parts of the body, viruses and pathogens, such as ebolaviruses, can hide in these locations from the immune system of the survivor. Among these areas are the cerebrospinal fluid, the testes, the interior of the eyes, the placenta, and the central nervous system. Each survivor has varying degrees of the virus’s persistence and prevalence in specific bodily areas.
In order to better understand how to treat and care for Ebola illness survivors, researchers continue to investigate the long-term impacts of ebolavirus infection, including viral persistence.