Formerly known as Ebola hemorrhagic fever, Ebola virus disease (EVD), is a severe illness in humans with a case fatality rate of up to 90%. It is one of the scariest, most highly infectious, and deadly diseases ever known to humankind.
Ebola first appeared in 1976 in two simultaneous outbreaks, one in a village near the Ebola River in the Democratic Republic of Congo and the other in a remote area of Sudan.
- The Ebola virus got its name from the river where the first outbreak emerged in 1976 – the Ebola River in the Democratic Republic of the Congo (formerly Zaire) in Africa.
- Fruit bats of the Pteropodidae family are considered to be the natural host of the Ebola virus.
- Ebola is not a respiratory disease and is not spread through the airborne route, coughing or sneezing. Scientists have found that the Ebola virus is not likely to become airborne. The virus is not spread through casual contact and water also.
- Infected fruits bats or primates (apes and monkeys) can transmit the Ebola virus. Dogs or cats are not able to spread Ebola to people or other animals.
- Mosquitoes that transmit many deadly diseases such as Malaria, Filariasis, and Japanese Encephalitis are not able to carry and transmit the Ebola virus.
- If an exposed person does not develop Ebola symptoms after 21 days, he/she will not have Ebola.
- Ebola is only spread from one person to another once symptoms begin. A person infected with Ebola cannot spread it to others until symptoms begin.
Ebola virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission. It transmits via the body fluids (blood, vomit, urine, feces, sweat, and other fluids) of a person who is sick with or had died from Ebola or via objects contaminated with the virus (like needles and syringes, etc.).
Infection occurs from direct contact (human to human transmission) through broken skin or mucous membranes with infected people’s blood or other bodily fluids or secretions (stool, urine, saliva, etc.). Infection can also occur if a healthy person’s broken skin or mucous membranes come into contact with environments contaminated with an Ebola patient’s infectious fluids, such as soiled clothing, bed linen, or used needles.
During an outbreak, those at higher risk of infection are:
- health workers;
- family members or others in close contact with infected people;
- mourners who have direct contact with the bodies of the deceased as part of burial ceremonies.
Signs and Symptoms
Sudden onset of fever, intense weakness, muscle pain, headache, and sore throat are typical signs and symptoms. This is followed by vomiting, diarrhea, rash, impaired kidney and liver function, and internal and external bleeding in some cases.
Laboratory findings include low white blood cell and platelet counts and elevated liver enzymes.
The incubation period, or the interval from infection to onset of symptoms, is from 2 to 21 days. The patients become contagious once they begin to show symptoms. They are not contagious during the incubation period.
Ebola virus disease infections can only be confirmed through laboratory testing.
5. When should someone seek medical care?
If a person has been in an area known to have Ebola virus disease or in contact with a person known or suspected to have Ebola and begin to have symptoms, they should seek medical care immediately.
Any cases of persons who are suspected of having the disease should be reported to the nearest health unit without delay. Prompt medical care is essential to improving the survival rate. It is also important to control the spread of the disease, and infection control procedures need to be started immediately.
Diagnosing Ebola in someone infected for only a few days is difficult because the early symptoms, such as fever, are nonspecific to Ebola infection and are seen often in patients with more commonly occurring diseases, such as malaria and typhoid fever.
However, if a person has the early symptoms of Ebola and has had contact with the blood or body fluids of a person sick with Ebola, contact with objects that have been contaminated with the blood or body fluids of a person sick with Ebola, or contact with infected animals, they should be isolated, and public health professionals notified. Samples from the patient can then be collected and tested to confirm infection.
|Timeline of Infection||Diagnostic tests available|
|Within a few days after symptoms begin||Antigen-capture enzyme-linked immunosorbent assay (ELISA) testing IgM ELISA, polymerase chain reaction (PCR), Virus isolation|
|Later in the disease course or after recovery||IgM and IgG antibodies|
|Retrospectively in deceased patients||Immunohistochemistry testing |
Download Laboratory Guidelines for Testing of Ebola Virus Disease: Click to Download
Prevention of Ebola Virus Disease
Currently, no licensed medicine or vaccine for the Ebola virus exists, but several products are under development.
Ebola Virus Disease is transmitted from Human to Human (H2H) through direct, physical contact with the bodily fluids (vomit, feces, urine, blood, etc.) of people who have been infected with or died from Ebola virus disease (EVD).
People at the highest risk of developing Ebola virus disease are health care workers who come in contact with patients suffering from Ebola virus disease and the family and friends of the infected individuals.
If you travel to or are in an area affected by an Ebola outbreak, or you are a healthcare worker or a family or friend of a person suffering from Ebola virus disease, below mentioned steps will help you to reduce the chances of contracting the Ebola virus disease.
- Hand washing is the best tool to combat any infectious disease, including Ebola. Practice careful hygiene. For example, wash your hands with soap and water or an alcohol-based hand sanitizer and avoid contact with blood and body fluids.
- Do not handle items that may have come in contact with an infected person’s blood or body fluids (such as clothes, bedding, needles, and medical equipment).
- Avoid funeral or burial rituals that require handling the body of someone who has died from Ebola.
- Avoid contact with bats and nonhuman primates or blood, fluids, and raw meat prepared from these animals.
- Avoid hospitals in West Africa where Ebola patients are being treated.
- After you return from Ebola-affected regions, monitor your health for 21 days and seek medical care immediately if you develop symptoms of Ebola.
- To protect yourself, your family, and your community from EVD transmission, immediately report to the nearest health facility if you develop symptoms of EVD, including high fever, body aches, joint pain, vomiting, diarrhea, or hemorrhaging.
Healthcare workers who may be exposed to people with Ebola should follow these steps:
- Wear protective clothing, including masks, gloves, gowns, and eye protection.
- Practice proper infection control and sterilization measures.
- Isolate patients with Ebola from other patients.
- Avoid direct contact with the bodies of people who have died from Ebola.
- Notify health officials if you have had direct contact with the blood or body fluids, such as but not limited to feces, saliva, urine, and vomit of a person who is sick with Ebola. The virus can enter the body through broken skin or unprotected mucous membranes in, for example, the eyes, nose, or mouth.
There is no FDA-approved vaccine available for Ebola. Severely ill patients require intensive supportive care. They are frequently dehydrated and need intravenous fluids or oral rehydration with solutions that contain electrolytes. There is currently no specific treatment to cure the disease.
Some patients will recover with the appropriate medical care.
To help control the further spread of the virus, people suspected or confirmed to have the disease should be isolated from other patients and treated by health workers using strict infection control precautions.