EbolaVirusDisease
Ebola, previously known as Ebola hemorrhagic fever, is a rare and deadly disease caused by infection with
one of the Ebola virus strains. Ebola can cause disease in humans and nonhuman primates (monkeys,
gorillas, and chimpanzees).
Ebola is caused by infection with a virus of the family Filoviridae, genus Ebolavirus. There are five identified
Ebola virus species, four of which are known to cause disease in humans: Ebola virus (Zaire ebolavirus);
Sudan virus (Sudan ebolavirus); Ta Forest virus (Ta Forest ebolavirus, formerly Cte dIvoire ebolavirus);
and Bundibugyo virus (Bundibugyo ebolavirus). The fifth, Reston virus (Reston ebolavirus), has caused
disease in nonhuman primates, but not in humans.
Ebola viruses are found in several African countries. Ebola was first discovered in 1976 near the Ebola River
in what is now the Democratic Republic of the Congo. Since then, outbreaks have appeared sporadically in
Africa.
The natural reservoir host of Ebola virus remains unknown. However, on the basis of evidence and the
nature of similar viruses, researchers believe that the virus is animal-borne and that bats are the most likely
reservoir. Four of the five virus strains occur in an animal host native to Africa.
SymptomsofEbolainclude
Fever
Severe headache
Muscle pain
Weakness
Fatigue
Diarrhea
Vomiting
Abdominal (stomach) pain
Unexplained hemorrhage (bleeding or bruising)
Symptoms may appear anywhere from 2 to 21 days after exposure to Ebola, but the average is 8 to 10
days.
Recovery from Ebola depends on good supportive clinical care and the patients immune response. People
who recover from Ebola infection develop antibodies that last for at least 10 years.
Transmission
When an infection occurs in humans, the virus can be spread to others through direct contact (through
broken skin or mucous membranes in, for example, the eyes, nose, or mouth) with
blood or body fluids (including but not limited to urine, saliva, sweat, feces, vomit, breast milk, and
semen) of a person who is sick with Ebola
objects (like needles and syringes) that have been contaminated with the virus
infected fruit bats or primates (apes and monkeys)
Diagnosis
Diagnosing Ebola in a person who has been infected for only a few days is difficult because the early
symptoms, such as fever, are nonspecific to Ebola infection and often are seen in patients with more
common diseases, such as malaria and typhoid fever.
However, if a person has the early symptoms(http://www.cdc.gov/vhf/ebola/symptoms/index.html) 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.
Laboratory tests used in diagnosis include:
Timeline of Infection
Within a few days after symptoms begin
Diagnostic tests available
*Antigen-capture enzyme-linked immunosorbent
assay (ELISA) testing
*IgM ELISA
*Polymerase chain reaction (PCR)
*Virus isolation
Later in disease course or after recovery
IgM and IgG antibodies
Retrospectively in deceased patients
Immunohistochemistry testing
PCR
Virus isolation
Prevention
There is no FDA-approved vaccine available for Ebola.
If you travel to or are in an area affected by an Ebola outbreak, make sure to do the following:
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 persons 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 facilities in West Africa where Ebola patients are being treated. The U.S. embassy or consulate is
often able to provide advice on facilities.
After you return, monitor your health for 21 days and seek medical care immediately if you develop
symptoms of Ebola(http://www.cdc.gov/vhf/ebola/symptoms/index.html).
Healthcare workers who may be exposed to people with Ebola should follow these steps:
Wear appropriate personal protective equipment (PPE).
Practice proper infection control and sterilization measures. For more information, see Information for
Healthcare Workers and Settings(http://www.cdc.gov/vhf/ebola/hcp/index.html).
Isolate patients with Ebola from other patients.
Avoid direct, unprotected 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, vomit, and semen 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.
RecommendedPersonalProtectiveEquipment
1.
PAPR or N95 respirator
A PAPR with a full face shield, helmet, or headpiece. Any reusable helmet or headpiece must be
covered with a single-use (disposable) hood that extends to the shoulders and fully covers the
neck and is compatible with the selected PAPR. The facility should follow manufacturers
instructions for decontamination of all reusable components and, based upon those instructions,
develop facility protocols that include the designation of responsible personnel who assure that the
equipment is appropriately reprocessed and that batteries are fully charged before reuse.
Single-use (disposable) N95 respirator in combination with single-use (disposable) surgical hood
extending to shoulders and single-use (disposable) full face shield.** If N95 respirators are used
instead of PAPRs, careful observation is required to ensure healthcare workers are not
inadvertently touching their faces under the face shield during patient care.
2.
3.
4.
5.
Single-use (disposable) fluid-resistant or impermeable gown that extends to at least mid-calf or
coverall without integrated hood. Coveralls with or without integrated socks are acceptable.
Single-use (disposable) nitrile examination gloves with extended cuffs. Two pairs of gloves should
be worn. At a minimum, outer gloves should have extended cuffs.
Single-use (disposable), fluid-resistant or impermeable boot covers that extend to at least mid-calf
or single-use (disposable) shoe covers. Boot and shoe covers should allow for ease of movement
and not present a slip hazard to the worker.
Single-use (disposable), fluid-resistant or impermeable apron that covers the torso to the level of
the mid-calf should be used if Ebola patients have vomiting or diarrhea. An apron provides
additional protection against exposure of the front of the body to body fluids or excrement. If a
PAPR will be worn, consider selecting an apron that ties behind the neck to facilitate easier
removal during the doffing procedure.
Treatment
No FDA-approved vaccine or medicine (e.g., antiviral drug) is available for Ebola.
Symptoms of Ebola and complications are treated as they appear. The following basic interventions, when
used early, can significantly improve the chances of survival:
Providing intravenous fluids (IV) and balancing electrolytes (body salts).
Maintaining oxygen status and blood pressure.
Treating other infections if they occur.
Experimental vaccines and treatments for Ebola are under development, but they have not yet been fully
tested for safety or effectiveness.
Recovery from Ebola depends on good supportive care and the patients immune response. People who
recover from Ebola infection develop antibodies that last for at least 10 years, possibly longer. It is not
known if people who recover are immune for life or if they can become infected with a different species of
Ebola. Some people who have recovered from Ebola have developed long-term complications, such as
joint and vision problems.
