Definition and Overview
The Ebola virus disease (EVD) is a serious, potentially life-threatening illness caused by a virus transmitted by wild animals but can also spread from human to human. Formerly known as Ebola hemorrhagic fever, the disease began in Central Africa, particularly in the remote villages near its tropical rainforests. However, due to its tendency to spread easily, outbreaks now affect even rural and urban areas. Currently, an outbreak is being experienced in a large part of West Africa encompassing Guinea, Sierra Leone, and Liberia. Records show that this is the largest Ebola outbreak so far.
Ebola causes a series of symptoms that significantly worsen in a short span of time and may eventually lead to internal and external bleeding that, in turn, cause low platelet counts, which can easily threaten the patient’s life.
There is currently no proven treatment for EVD, so treatment currently only focuses on supportive-care, such as addressing the symptoms to improve the patient’s chance of survival.
Causes of Condition
The main cause of the illness is the Ebola virus, which originates from wild animals. However, once a person gets infected, he can pass it on to other people through contact with blood and other bodily fluids. The virus cannot be destroyed by washing the hands. Other than direct contact with an infected person or his bodily fluids, the virus can also spread from an infected animal as well as from contaminated objects, such as beddings and clothing.
It is most commonly passed on to people who are taking care of patients who are already infected, such as hospital staff and family members, so care providers need to be very careful and to apply strict precautions when touching patients or cleaning up waste materials such as urine, stool, or vomit. Laboratory workers who handle blood samples also face a heightened risk. To prevent infections, people who interact with infected people need to wear protective clothing and other equipment.
However, the Ebola virus only begins to spread when the symptoms begin. This means that a person who has become infected with Ebola but does not feel any symptoms is not infectious yet. Once the symptoms begin, however, the patient’s condition tends to worsen rapidly, and in most cases, the patient is immediately placed in a quarantined area. This means infectious individuals do not usually stay in close contact with the community for a long time. This helps minimize the spread of the disease to a certain extent.
Despite the current widespread outbreak in West Africa, the risk of Ebola spreading to other countries is very low.
The common symptoms of Ebola include:
These initial symptoms may begin to show as early as two days after the patient becomes infected or as late as 21 days after the infection. Once they begin, however, the patient’s condition is expected to worsen fast and cause more severe symptoms, such as:
- Abdominal pain
- Impaired kidney function
- Impaired liver function
- Internal bleeding
- Bleeding from the eyes, nose, ears, or mouth
The symptoms above are very common and can be caused by several other infectious diseases such as malaria and typhoid fever, so it is a challenge for healthcare professionals to diagnose Ebola cases. Thus, the patient’s background, medical history, and recent travels are the three most important factors that are first considered even before the test results come in. Tests that are used to confirm an Ebola diagnosis include:
- Antigen-capture detection
- Electron microscopy
- Antibody-capture enzyme-linked immunosorbent assay (also known as ELISA)
- Serum neutralization test
- Virus isolation through cell culture
- Reverse transcriptase polymerase chain reaction assay (also known as RT-PCR)
These tests are considered under maximum biological containment procedures as samples from infected individuals are considered as an extreme biohazard.
There are also strict procedures in place for flight crew and border authorities who identify possible Ebola cases based on symptoms exhibited during flights and immigration processes coming from Africa. These procedures aim to reduce transmission especially in the close confinement within the plane or airport. So far, however, no patient has become infected by being on the same flight as an Ebola victim.
Who to See and Types of Treatments Available
Due to the localized source of the virus, patients who live in or were on a recent trip to Africa and experienced these symptoms within 21 days of getting back to their home countries should stay at home to minimize contact with other individuals and should call for emergency medical care. It is best to call for an ambulance so that the hospital can prepare for the patient’s arrival. This is part of the protocol in handling suspected Ebola cases to minimize the risk of spreading the infection in the hospital.
Ebola cases are handled by infectious disease specialists, who are doctors of internal medicine specializing in the handling, treatment, management, and containment of all types of infectious diseases. These doctors undergo special training in dealing with viral infections such as Ebola as well as other types of infections (i.e. bacterial, fungi, and parasite infections).
There is currently no proven treatment that can fight the Ebola virus, so medical care focuses mostly on relieving symptoms and keeping the patient’s condition from getting worse. Due to the lack of available treatment, around 50 to 90 percent of Ebola cases lead to the deaths of the victims.
A patient’s survival is largely affected by these factors:
- How his immune system can effectively fight the virus – It is possible for the immune system to develop antibodies that can fight the infection, leading to the recovery of the patient. These antibodies can protect the individual for around ten years.
- How well he receives supportive-care therapies for his symptoms
- How early supportive-care begins - Since symptoms get worse quickly, if a person seeks treatment at the first onset of symptoms, he will be able to receive supportive-care before the disease causes severe damage to his body. Thus, the earlier an infected person receives medical attention, the higher his chances of survival.
Supportive-care therapies involve:
- Oral and intravenous rehydration to prevent dehydration
- Electrolytes stabilization
- Immune therapies
- Blood pressure regulation
In some cases of successful recovery from the disease, the patients suffered from long-term complications such as problems affecting their vision or their joints.
The lack of effective treatment for Ebola stresses the importance of controlling infections, which can only be done with the cooperation of entire communities and strict implementation of risk reduction protocols. These protocols involve several factors, namely:
- Reducing transmission from wildlife to humans
- Reducing human-to-human transmission through blood, bodily waste, or sexual intercourse
- Reducing transmission through contaminated materials
- Controlling infection in the healthcare and laboratory setting
- Keeping the infection from crossing borders
There are also two other important and unique aspects of controlling Ebola risk:
Prompt and safe burials – The Ebola virus is not destroyed when the person dies, which means a dead person’s blood remains infected and can still transmit the disease.
Proper instruction for recovered individuals – Men who recover from Ebola may still have the virus in their semen for a certain amount of time, which tend to differ for every individual. In some cases, it took as long as nine months for the virus to leave the patient’s semen.
Aside from treatment, researchers are also working on developing a vaccine for the disease. At present, there are two potential vaccines that are currently undergoing testing.
Centers for Disease Control and Prevention. Ebola (Ebola Virus Disease). Updated October 8, 2014. http://www.cdc.gov/vhf/ebola/index.html. Accessed 10/9/2014.
Gostin LO, Lucey D, Phelan A. The Ebola Epidemic: A Global Health Emergency. JAMA. 2014;312(11):1095-1096. PMID: 25111044. http://www.ncbi.nlm.nih.gov/pubmed/25111044.
World Health Organization. Ebola Virus Disease. Updated September 2014. http://www.who.int/mediacentre/factsheets/fs103/en/. Accessed 10/9/2014.