Essential knowledge about Ebola


Disease background

Ebola hemorrhagic fever, or just Ebola for short, is a severe disease often leading to death in humans and non-human primates (such as monkeys, gorillas, and chimpanzees). Five different Ebola virus species have been identified, and four of these cause disease in humans. The first Ebola species was discovered in 1976 near the Ebola River in what is now the Democratic Republic of Congo. Since then, sporadic outbreaks have occurred in Africa. Researchers believe the virus is carried in bats, but the exact source is unknown.

Ebola has been in the news over the last few months as the largest outbreak in history has developed in Western Africa. Several American healthcare workers who have worked with patients in Africa have become sick and been brought back to the United States for treatment. On September 30, 2014 the first case of Ebola was diagnosed in the United States in a patient who had recently traveled from Africa. 

Signs and symptoms

A person infected with Ebola is not contagious until symptoms appear. Symptoms usually begin eight to 10 days after a person has been exposed to an ill Ebola patient. However, symptoms may begin anywhere from two to 21 days after the exposure. 

Typical signs and symptoms of Ebola infection are:

  • Fever (greater than 101.5oF)
  • Severe headache
  • Muscle pain
  • Vomiting
  • Diarrhea
  • Stomach pain
  • Unexplained bleeding or bruising

How is the virus spread?

The virus can enter the body through broken skin or unprotected mucous membranes of the eyes, nose, or mouth. When a person is sick with Ebola there are several ways the virus can be spread to others.

  • Direct contact with the blood or body fluids (feces, saliva, urine, vomit, and semen) of the sick person.
  • Contact with objects (needles and syringes) that have been used and contain blood or body fluids of the infected person.


Currently, there are no specific vaccines or medicines (such as antiviral drugs) that have been proven to work against the Ebola virus. Sick patients are treated by providing relief to their symptoms as they appear. Typical treatment can involve providing intravenous (IV) fluids and monitoring body electrolytes, maintaining oxygen status and blood pressure, and treating other infections as they happen. 

Is there danger of Ebola spreading in the U.S.?

Please keep in mind the likelihood of contracting Ebola is considered extremely low unless there is direct exposure to the body fluids of an infected person. Ebola in not spread through casual contact; therefore, the risk of an outbreak in the U.S. is very low. The further spread of Ebola can be stopped through finding cases, isolating ill people, contacting people exposed to ill persons, and further isolating contacts if they develop symptoms. The U.S. public health and medical systems have had prior experience with sporadic cases of diseases such as Ebola. In the past decade, the United States had five imported cases of Viral Hemorrhagic Fever disease similar to Ebola. None resulted in transmission in the United States.

Advice for travelers

Centers for Disease Control and Prevention (CDC) has issued a travel notice for Ebola affected countries, which means travelers should avoid non-essential travel to Guinea, Liberia, and Sierra Leone. For current travel advisories please visit http://wwwnc.cdc.gov/travel/notices.

  • If you are returning from a country where the outbreak is occurring:
    • After you return, monitor your health for 21 days.
    • Seek medical care immediately if you develop the signs and symptoms of Ebola infection.
    • Tell your doctor about your recent travel and symptoms before you go to the office or emergency room. Advance notice will help your doctor care for you and protect other people who may be in the facility or office.  
  • If you are traveling to an area where the outbreak is occurring:
    • Wash your hands frequently or use an alcohol-based sanitizer.
    • Seek medical care immediately if you develop symptoms of Ebola virus.
      • Do not travel anywhere else besides a healthcare facility.


Additional resources


WHO—Ebola virus disease 

HHS—Ebola Outbreak 2014: Information Resources

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