What is the Ebola Virus?

Ebola Hemorrhagic Fever

Ebola hemorrhagic fever (Ebola HF) is one of numerous Viral Hemorrhagic Fevers. It is a severe, often fatal disease in humans and nonhuman primates (such as monkeys, gorillas, and chimpanzees). When infection occurs, symptoms usually begin abruptly. The first Ebola virus species was discovered in 1976 in what is now the Democratic Republic of the Congo near the Ebola River. Since then, outbreaks have appeared sporadically.

Risk of Exposure

If you or someone close to you has traveled within the past three weeks to or from the following countries, you should monitor your health for the next several days, up to 21 days.

  • Guinea
  • Liberia
  • Sierra Leone
  • Nigeria

Transmission

Because the natural reservoir of Ebola viruses has not yet been proven, the manner in which the virus first appears in a human at the start of an outbreak is unknown. However, researchers have hypothesized that the first patient becomes infected through contact with an infected animal. When an infection does occur in humans, there are several ways in which the virus can be transmitted to others. These include:

  • direct contact with the blood or secretions of an infected person
  • exposure to objects (such as needles) that have been contaminated with infected secretions

The viruses that cause Ebola are often spread through families and friends because they come in close contact with infectious secretions when caring for ill persons.

Ebola poses little risk to the US general population and is not contagious until symptoms appear. It is spread through direct contact with body fluids (blood, urine, feces, saliva, semen, and other secretions) of an infected person, or with objects like needles that have been contaminated with body secretions. This includes through intimate contact, such as sex, since Ebola can still be found in semen for 7 weeks after a person has recovered.

Signs and Symptoms

Symptoms of Ebola typically include:

  • Fever
  • Headache
  • Joint and muscle aches
  • Weakness
  • Diarrhea
  • Vomiting
  • Stomach pain
  • Lack of appetite

Some patients may experience:

  • A Rash
  • Red Eyes
  • Hiccups
  • Cough
  • Sore throat
  • Chest pain
  • Difficulty breathing
  • Difficulty swallowing
  • Bleeding inside and outside of the body

Symptoms may appear anywhere from 2 to 21 days after exposure to Ebola virus though 8-10 days is most common. Some who become sick with Ebola are able to recover, while others do not. The reasons behind this are not yet fully understood. However, it is known that patients who die usually have not developed a significant immune response to the virus at the time of death.

Treatment

Standard treatment for Ebola is still limited to supportive therapy. This consists of: • balancing the patient's fluids and electrolytes • maintaining their oxygen status and blood pressure • treating them for any complicating infections Timely treatment of Ebola is important but challenging since the disease is difficult to diagnose clinically in the early stages of infection. Because early symptoms such as headache and fever are nonspecific to Ebola viruses, cases of Ebola may be initially misdiagnosed.

However, if a person has the early symptoms of Ebola and there is reason to believe that Ebola HF should be considered, the patient should be isolated and public health professionals notified. Supportive therapy can continue with proper protective clothing until samples from the patient are tested to confirm infection.

Prevention

The prevention of Ebola presents many challenges. Because it is still unknown how exactly people are infected with Ebola, there are few established primary prevention measures.
When cases of the disease do appear, there is increased risk of transmission within health care settings. Therefore, health care workers must be able to recognize a case of Ebola HF and be ready to employ practical viral hemorrhagic fever isolation precautions or barrier nursing techniques. They should also have the capability to request diagnostic tests or prepare samples for shipping and testing elsewhere.

Barrier nursing techniques include:

  • wearing of protective clothing (such as masks, gloves, gowns, and goggles)
  • the use of infection-control measures (such as complete equipment sterilization and routine use of disinfectant)
  • isolation of Ebola HF patients from contact with unprotected persons

The aim of all of these techniques is to avoid contact with the blood or secretions of an infected patient. If a patient with Ebola HF dies, it is equally important that direct contact with the body of the deceased patient be prevented.

CDC, in conjunction with the World Health Organization, has developed a set of guidelines to help prevent and control the spread of Ebola. Entitled Infection Control for Viral Hemorrhagic Fevers In the African Health Care Setting, the manual describes how to:

  • recognize cases of viral hemorrhagic fever (such as Ebola HF)
  • prevent further transmission in health care setting by using locally available materials and minimal financial resources