Ebola virus disease (EVD), also known as Ebola hemorrhagic fever, is a severe, often fatal illness in humans. It is caused by the Ebola virus, which is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.
The disease was first identified in 1976 in two simultaneous outbreaks, one in Nzara (now in South Sudan), and the other in Yambuku, Democratic Republic of Congo. The latter occurred near the Ebola River, from which the disease takes its name.
Ebola virus disease is characterized by sudden onset of fever, fatigue, muscle pain, headache, and sore throat, followed by vomiting, diarrhea, rash, symptoms of impaired kidney and liver function, and in some cases, both internal and external bleeding. People remain infectious as long as their blood contains the virus.
EVD is a particularly dangerous disease with case fatality rates varying from 25% to 90% in past outbreaks. There is no proven treatment available for EVD. However, a range of potential treatments including blood products, immune therapies and drug therapies are currently being evaluated. An effective vaccine, known as rVSV-ZEBOV, has been developed and used in major outbreaks.
Prevention involves measures to reduce the risk of wildlife-to-human transmission through contact with infected fruit bats or monkeys/apes and the consumption of their raw meat. As well measures to prevent the spread through direct contact with the blood, secretions, organs or other bodily fluids of infected people, and indirect contact with environments contaminated with such fluids.
Causes of Ebola virus disease
Ebola Virus Disease (EVD) is caused primarily by the Ebola virus, which is a type of RNA virus in the family Filoviridae. The disease is considered a zoonotic disease because it is initially transmitted to people from wild animals and then spreads in the human population through human-to-human transmission.
1. Animal Transmission: Researchers believe that the disease is most likely initially transmitted to humans through contact with infected animals’ blood, secretions, or other bodily fluids. Certain species of fruit bats in Africa are the most broadly accepted natural reservoirs of the Ebola virus, although the virus has also been found in other mammals such as monkeys, chimpanzees, and antelopes.
2. Human-to-Human Transmission: Once a human has contracted the disease, it can be transmitted to others through direct contact with the blood, secretions, organs, or other bodily fluids of infected people, and with surfaces and materials contaminated with these fluids. This can happen either through skin breaks or mucous membranes in the eyes, nose, or mouth.
3. Healthcare Settings: Transmission can also occur in healthcare settings if staff do not wear protective clothing, such as masks, gowns, and gloves, correctly or if contaminated instruments, such as needles, are reused.
4. Traditional Rituals: In certain African cultures, traditional funeral rituals may involve washing the bodies of the deceased, leading to another pathway for transmission if the deceased individual died of Ebola.
5. Sexual Transmission: Though less common, Ebola can also spread through sexual contact. The virus can persist in some body fluids, including semen, of a patient who has recovered from EVD, even if they no longer have symptoms of severe illness.
It is important to note that a person infected with Ebola is not contagious until symptoms begin to appear.
Risk Factors of Ebola virus disease
Ebola virus disease (EVD), formerly known as Ebola haemorrhagic fever, is a severe, often fatal illness in humans. The risk factors associated with the Ebola virus disease include:
1. Travel to areas experiencing an outbreak: Travelers to or residents of areas where Ebola virus outbreaks have occurred are at a higher risk of infection.
2. Contact with infected animals: Wild animals, like fruit bats, porcupines, and non-human primates, are believed to be the primary source of the Ebola virus. Infection can occur through direct contact with an infected animal’s blood, body fluids, or meat.
3. Direct contact with body fluids or tissues of an infected person: Ebola is spread through direct contact with blood, bodily fluids, organs, and tissues of infected individuals.
4. Exposure in healthcare settings: Healthcare workers treating Ebola virus disease patients are at high risk if they do not use personal protective equipment correctly or at all.
5. Unsafe burial practices: In certain cultures, the deceased may be washed and their bodies touched by family or community members, which can spread the virus if the deceased individual had Ebola.
6. Sexual transmission: Even after recovery, Ebola can persist in certain body fluids, including semen. Therefore, sexual transmission of the virus is possible, even if the infected individual has recovered from the disease.
In general, individuals with compromised immune systems would be at higher risk, and those coming into contact with infected patients or their fluids without proper protective measures would be at a higher risk as well.
Signs and Symptoms of Ebola virus disease
Ebola virus disease, commonly known as EVD or Ebola, is a rare and deadly disease caused by infection with one of the Ebola virus strains. Here are some of its signs and symptoms:
Early Symptoms (usually starts 2-21 days after infection):
1. Fever
2. Severe headache
3. Fatigue
4. Muscle pain
5. Chills
Later Symptoms (as the disease progresses):
1. Diarrhea and vomiting
2. Abdominal stomach pain
3. Unexplained hemorrhaging (bleeding or bruising)
Other symptoms can include joint and muscle aches, lack of appetite, and difficulty breathing or swallowing. Individuals may also present with a rash, red eyes, hiccups, chest pain, and in some cases, internal and external bleeding can occur (such as bloody stool or bleeding gums).
Anyone exhibiting these symptoms should seek medical care immediately, especially if there is a possibility they have been in contact with someone infected with Ebola, or have travelled to an area where Ebola has been reported. The disease is serious and often fatal, so early and appropriate treatment significantly improves the chance of survival.
Note that early symptoms of EVD are quite similar to other more common diseases, like influenza, malaria or typhoid fever. Therefore, diagnosis should be carried out by a healthcare provider to confirm the disease.
Diagnosis Ebola virus disease
Ebola virus disease, also known simply as Ebola, is a severe and often fatal illness that occurs in humans and some animals. It is caused by the Ebola virus, which is named after the Ebola River in the Democratic Republic of Congo where the disease was first identified in 1976.
The Ebola virus can be transmitted to humans from wild animals and then spreads through human-to-human transmission via direct contact with the blood, secretions, organs, or other body fluids of infected people, and with surfaces and materials contaminated with these fluids.
Symptoms of Ebola virus disease typically include the sudden onset of fever fatigue, muscle pain, headache, and sore throat. This is typically followed by vomiting, diarrhea, rash, symptoms of impaired kidney and liver function, and in some cases, both internal and external bleeding.
Diagnosis of Ebola is complex and can only be confirmed through laboratory testing, such as antigen-capture enzyme-linked immunosorbent assay (ELISA) testing, serum neutralization testing, reverse transcriptase polymerase chain reaction (RT-PCR) assay, electron microscopy, and virus isolation by cell culture.
There is currently no proven treatment for Ebola virus disease, but rehydration with oral or intravenous fluids and treatment of specific symptoms can improve survival. A range of potential treatments including blood products, immune therapies, and drug therapies are currently being evaluated. A vaccine against Ebola, known as the Ebola vaccine rVSV-ZEBOV, has also been shown to be highly protective against the virus.
People who recover from Ebola virus disease develop antibodies that last for at least 10 years, possibly longer. It isn’t known, however, if they are immune for life or if they can become infected with a different species of Ebola. Despite surviving the disease, recovery can be a slow process and complications, such as joint pain and vision problems, may linger or occur after recovery.
Treatment of Ebola virus disease
There’s currently no proven cure for Ebola, but treatment can increase the chance of survival. Care includes an experimental serum that destroys infected cells, supportive care rehydration with oral or intravenous fluids to treat dehydration, and pain management.
Treatments for complications of Ebola virus may be administered as well. These include the following:
1. Maintaining oxygen status and blood pressure
2. Providing treatments for other infections as needed
3. Treating symptoms as they appear (for example: nausea, vomiting, diarrhea, rash, pain, etc.)
It’s necessary to point out that early detection of the Ebola virus is key to survival, as it allows for the early commencement of treatment.
Furthermore, patients will be isolated from other people and treated by health care professionals who’ll take precautions to prevent the virus from spreading.
There are vaccines that can prevent infection, but they’re not widely available. During an outbreak, healthcare workers and people who might have been in contact with infected individuals are often the first to receive these vaccines.
It is recommended to have proper hygiene and avoid contact with infected people or animals to prevent the disease.
Medications commonly used for Ebola virus disease
Treatment for Ebola Virus Disease (EVD) is primarily supportive, with rehydration and symptomatic treatment being vital. However, there are specific antiviral drugs that have been developed and used to treat Ebola, including:
1. ZMapp: This is a combination of three different antibodies that bind to the protein of the Ebola virus. It has been used on a compassionate basis in past Ebola outbreaks since there’s limited availability.
2. Remdesivir (GS-5734): This is a broad-spectrum antiviral medication originally developed to treat Hepatitis C and later tested for Ebola. It is among the treatments used on patients in the DRC during the 2018-2020 outbreak. It has also been used recently to treat severe cases of COVID-19.
3. REGN-EB3: This is a cocktail of three monoclonal antibodies (REGN3470, REGN3471, and REGN3479) developed by Regeneron. This treatment has shown promise in treating the Ebola virus.
4. mAb114: This is another monoclonal antibody derived from a human survivor of the 1995 Ebola outbreak in Kikwit, Zaire (now the Democratic Republic of the Congo). It was found to be highly effective and safe in preventing death from the Ebola virus.
There are also vaccines which have been developed to prevent Ebola, the most notable being Ervebo (rVSV-ZEBOV) which was approved by the FDA in 2019. Please note that the context of treatments frequently changes according to the clinical trials and the evolving body of research.
Prevention of Ebola virus disease
Preventing the spread of Ebola virus disease involves several crucial steps:
1. Hygiene: Regular handwashing is important. Use soap and water or, alternatively, an alcohol-based hand sanitizer. Ebola can enter the body through broken skin, so make sure your skin is healthy and hydrating often.
2. Avoid Contact With Infected People: Ebola virus spreads through direct contact with the bodily fluids of someone who is sick with the disease. Healthcare workers can come into contact with the virus by handling a patient’s contaminated clothing or bed linens.
3. Protective Clothing: Healthcare workers should always wear appropriate protective clothing while dealing with patients who could be infected. This includes masks, gloves, gowns, and goggles.
4. Quarantine: Patients infected with Ebola should be isolated from the public immediately to prevent the spread of the disease.
5. Safe Burials: The bodies of deceased victims can still spread the virus. It’s very important that the bodies are handled and buried properly and safely.
6. Avoid Bushmeat: In regions where Ebola is prevalent, bushmeat (wild animals hunted for food) can potentially carry the disease.
7. Vaccination: There is an Ebola vaccine that provides some protection against the disease. It’s mainly used for healthcare workers who are likely to be at risk because of caring for infected patients.
8. Regular Screening & Early Detection: Early recognition of Ebola symptoms is critical as early treatment can improve survival. Regular health screenings in high-risk areas can help detect the disease.
9. Reporting: Any suspected case of Ebola should be reported immediately to the local health department for rapid action.
10. Travel Precautions: During Ebola outbreaks, avoid traveling to affected regions if possible.
Prevention is key in managing the spread of Ebola virus disease and keeping people safe. Remember, these methods are important for those who live in or travel to areas where the virus is prevalent, and for healthcare workers who might be exposed.
FAQ’s about Ebola virus disease
1. What is Ebola Virus Disease (EVD)?
Ebola Virus Disease (EVD) is a severe, often fatal illness affecting humans and other primates, caused by the Ebola virus. It was first identified in 1976 near the Ebola River in what is now the Democratic Republic of Congo.
2. How is Ebola transmitted?
Ebola can spread to people through direct contact with the blood, body fluids or tissues of a person who is sick with or has died from EVD. This can occur when a person touches contaminated objects, like needles or bedsheets. It can also be transmitted through contact with infected wildlife.
3. What are the symptoms of EVD?
Symptoms of EVD include fever, severe headache, muscle pain, vomiting, diarrhea, stomach pain, or unexplained bleeding or bruising. Symptoms may appear from 2 to 21 days after exposure to the virus, but the average is 8 to 10 days.
4. How is EVD diagnosed?
Diagnosis is usually made by testing blood, urine or saliva for the presence of the virus, or by testing a sample of tissue from a sick person. Due to the severe nature of the disease, these tests are performed under strict safety conditions.
5. What are the treatments for EVD?
There is no specific treatment for EVD. However, supportive care such as rehydration and treatment of specific symptoms can improve a patient’s chances of survival. Recently, two experimental treatments have shown promise in treating infected individuals.
6. Is there a vaccine for Ebola?
Yes, there is a vaccine for Ebola that has been found to be safe and effective in preventing Ebola infection.
7. Should I be worried about Ebola in my community?
The risk of getting EVD is very low unless you’ve had direct contact with the body fluids of a person sick with or has died from EVD, handled bats or non-human primates from affected areas, or have been in contact with semen from a man who has recovered from EVD. Healthcare workers are at higher risk and should use appropriate protective equipment.
8. How can EVD be prevented?
Prevention includes avoiding direct contact with sick or dead people or animals in areas where there is an Ebola outbreak, good hand hygiene, and safe burial practices. Vaccination is also an effective prevention method in high-risk areas.
9. What should I do if I think I have symptoms of Ebola?
If you think you have symptoms of EVD and have been in an area where the virus is found or have been in contact with someone who is sick with EVD, seek medical care immediately and tell your healthcare provider about your travel history or contact.
10. Can Ebola be eradicated?
Eradication of Ebola is challenging due to the nature of its transmission and its reservoir in animals. However, it can be controlled through coordinated international efforts, strong health systems, and community engagement.
Useful links
Ebola Virus Disease (EVD), also known as Ebola, is a deadly illness caused by the Ebola virus. This virus was first discovered in 1976 near the Ebola River in the Democratic Republic of Congo. The disease is severe and often fatal in humans, and it spreads through contact with the body fluids of an infected person or animal.
Key areas of interest in Ebola virus disease are its epidemiology, pathogenesis, diagnosis, treatment, and prevention. Here are useful links from recognized academic journals regarding Ebola:
Please be sure to check for each journal’s access and copyright restrictions. Some content may be behind a paywall or available only through specific institutional access.
Complications of Ebola virus disease
Ebola Virus Disease (EVD) is a rare and deadly disease caused by infection with one of the Ebola virus strains. Complications can include:
1. Immediate complications: These include severe dehydration due to vomiting and diarrhea, shock, failure of multiple organ systems, severe bleeding, and damage to the vascular system.
2. Long-term complications: Ebola can also have lingering effects that persist after the patient has recovered, a condition often referred to as ‘post-Ebola syndrome.’ Symptoms can include joint and muscle pain, vision problems, inflammation of the tissues lining the inside of the eyes (uveitis), severe headaches, fatigue, loss of appetite, difficulty sleeping, and in some cases, mental and neurologic health issues.
3. Complications related to transmission: Healthcare workers and family members taking care of an infected person are at the highest risk of getting infected themselves, especially if they are not using proper protective measures.
4. Societal and psychological complications: Outbreaks of Ebola can have devastating effects on communities – fear and stigma can lead to social isolation of patients and survivors. Health systems can also be seriously disrupted during outbreaks, potentially causing indirect health impacts.
5. Pregnancy-related complications: Pregnant women with EVD have high rates of miscarriage, premature delivery and neonatal death.
6. Risk of reinfection: There is also a risk of reinfection from persistent virus presence in certain body fluids of recovered patients, such as semen, where the virus can persist for several months after recovery from illness.
Seeking prompt medical attention and rigorous supportive care to manage hydration and manage symptoms is crucial and can significantly improve survival chances.
Home remedies of Ebola virus disease
Ebola virus disease is a severe and often deadly illness that can occur in humans and primates (such as monkeys and gorillas). Currently, there are no confirmed home remedies or over-the-counter treatments for Ebola virus disease. This very serious disease requires intensive supportive care.
Most often, treatment consists of what’s called supportive care, which may involve:
1. Rehydrating the patient.
2. Maintaining the patient’s oxygen status and blood pressure.
3. Managing any complicating infections.
Prevention strategies, such as avoiding areas of known outbreaks, not handling remains of victims of Ebola virus disease, and avoiding contact with bodily fluids of those infected, can help reduce the risk of infection.
It’s also crucial that you seek immediate medical attention if you believe you have been exposed to Ebola virus. Health care professionals have the knowledge and resources necessary to manage the disease and, in many cases, they can help improve the likelihood of survival with early intervention.
There are vaccines under development and some, like rVSV-ZEBOV vaccine, are being used under compassionate grounds in outbreaks. For up-to-date information on Ebola treatment and prevention, please refer to World Health Organization (WHO) or Centers for Disease Control and Prevention (CDC) guidelines.