Infectious diseases Internal Medicine



Ebola is a filovirus (RNA virus) that causes viral hemorrhagic fever. Other viruses that give similar clinical picture are Marburg, Lassa, and Crimean Congo viruses.

There are five different Ebola virus serotypes, four of which are human pathogens. The disease has been named by the Ebola River in the Democratic Republic of Congo (Zaire) where the disease was discovered in 1976. About 20 minor outbreaks have previously been reported in rural areas in central Africa with a mortality rate ranging between 25 and 88 percent. Most often, the outbreaks have subsided within a few months.

A major outbreak that started in early 2014 deviated from previous outbreaks and was the largest so far. The outbreak had a wide geographical spread with a large number of cases in Guinea, Liberia, Sierra Leone. In total, more than 10,000 people died and the mortality was estimated to be over 40-50%. The outbreak was the first to occur in western Africa, affecting not only the countryside but also densely populated large cities.

In the Democratic Republic of Congo, there have historically been several minor outbreaks in the countryside. However, a new outbreak has been reported in Congo Kinshasa in May 2018, which has spread to the metropolitan region and the large city of Goma in the eastern part of the country. It is estimated that just over 2,000 people have so far been infected with a high mortality rate (about 50%). New vaccines are offered to patients suspected to be infected, but the vaccination has encountered problems due to political instability and lack of infrastructure.

The outbreak in West Africa in 2014 included Guinea, Liberia, Sierra Leone, and border areas of their neighboring countries, notably Ivory Coast, Guinea-Bissau, and Mali.

Introduction – Ebola

The fruit bat is considered the natural host for Ebola and is a reservoir for the virus. The bat ​​transmits ebola viruses to monkeys and mammals (eg chimpanzees, gorillas, forest antelopes, and porcupines) who contract hemorrhagic fever. By being in contact with sick animals or infected bats, people are contracting the disease. Further virus transmission between people occurs through contact with infected body fluids within families, in hospitals and in connection with funeral ceremonies if one has close contact with the dead body.

Transmission routes

There is a high risk of infection upon contact with infected body fluids from living or dead humans such as:

  • Blood
  • Vomiting
  • Saliva
  • Feces
  • Urine
  • Semen

There is a high risk of being infected by unprotected healthcare personnel, as well as laboratory employees, who are exposed to infected body fluids or contaminated instruments or objects. Ebola virus can survive several days in a dry and liquid state. Nosocomial dissemination is a fundamental cause of ebola outbreaks. Participating in funeral ceremonies for people who have died in Ebola poses a risk of infection if you are in any way in close contact with the dead person or with body fluids from the dead person.

There is a risk that the infection can be transmitted after unprotected sexual contact with infected people up to three months after an infected person has recovered from Ebola.

Otherwise, the risk of being infected by Ebola is considered to be very low.

Incubation Period

The incubation period is usually 4-10 days but may vary between 2 and 21 days.

Symptoms – Ebola

  • Rapid debut of high fever
  • Pain in muscles, joints, and the head
  • Nausea/vomiting
  • Diarrhea
  • Abdominal pain and pronounced weakness
  • Conjunctivitis and pharyngitis with cold sores
  • Maculopapular rash is sometimes seen after 5 days of illness
  • Bleeding from the gastrointestinal tract, skin and mucous membranes
  • Deaths from the disease usually occur on days 7-16 and are associated with severe bleeding and hypovolemic shock, with cardiac failure being the cause of death.
  • In pregnancy, the outcome is almost always fatal.
  • Mortality rates are higher in the elderly than those in their 20s. Young children have very high mortality rates.
  • Ebola can remain in some tissues, such as the eye, brain, semen, for a long time after acute illness and, in rare cases, give rise to new ailments, such as meningoencephalitis or uveitis.

Differential Diagnoses – Ebola

  • Malaria
  • Typhoid fever
  • Shigellosis
  • Leptospirosis
  • Dengue fever
  • Lassa fever

Treatment – Ebola

Specific drug therapy against the Ebola virus that is scientifically proven is lacking. The treatment is consisting of supportive therapy primarily aimed at failing organ functions and replacing fluid and blood losses. Fluid, blood and platelet transfusions are given and respiration can be supported by respiratory therapy. Particularly fluid delivery is important as the patient can lose up to 5-10 liters of fluid per day.

In trials, humanized monoclonal antibodies and serum donated from convalescent centers have been tested on isolated cases, with uncertain effects.

Prophylaxis – Ebola

  • Good hand hygiene.
  • Wash and peel fruits and vegetables.
  • Avoid contact with blood and body fluids from a person or body infected with the Ebola virus.
  • Avoid close contact with all wildlife, living as well as dead, especially monkeys, various species of forest antelopes, rodents, guinea pigs, and flying dogs, as well as all forms of wild animal meat.
  • Always avoid unprotected sex and especially with a person who is or has been infected with Ebola.
  • Avoid contact with all types of instruments, such as needles and objects that have been in contact with blood or body fluids.
  • Avoid staying in environments where fruit bats and other types of bats live, such as caves and mines.
  • A scientifically proved vaccine is missing, but a vaccine in a Phase III trial has been shown to have a good effect and is expected to be on the market in the future.

Emergency Department Management

A patient who is exposed to ebola, or is deemed to have “mild risk” or “high risk” of having the Ebola infection, should be treated with the same medical competence and quality that is normally offered to patients with other diseases while taking necessary considerations to avoid transmission of infection to staff and co-patients.

Patients with clinical symptoms

Clinical symptoms are often nonspecific at an early stage. Travel history is important for raising suspicion about Ebola. Infectious diseases doctors as well as infection control doctors should be involved early in the treatment.

Mild risk of Ebola

Mild risk is present for a patient who develops a fever (above or equal to 38.6 ° C) within three weeks of returning from Ebola risk areas and where one or more of the following factors is present:

  • The person has been in contact with wildlife.
  • The person has visited/worked in healthcare in an Ebola risk area.
  • The person has worked in a laboratory where ebola is handled.
  • The person has lived in a district/province with significant spread of Ebola.

A patient who is judged to have a “mild risk” for ebola is immediately transferred to an infectious diseases (ID) clinic. While awaiting transport to the ID clinic, the patient is cared for in a separate room and must not be allowed to stay or be allowed to enter waiting rooms. All staff caring for the patient must follow basic hygiene rules including protection against airborne contaminants. Protection against airborne contamination includes adaptation tested, liquid resistant, disposable respiratory protection class FFP32, liquid resistant, disposable coat, surgical cap, visor (attached to head), and gloves (if vomiting or diarrhea is present).

The amount of caregivers is reduced as much as possible. It is important that testing for Ebola takes place without delay and that malaria testing is done in parallel since malaria is a common and life-threatening disease in febrile travelers from Africa.

High risk of ebola

High risk is characterized by a patient who develops fever (equal to or above 38.6 ° C) within three weeks of returning from the risk area of ​​ebola and where one or more of the following factors are present:

  • The patient has unexplained bleeding manifestations (not just bloody diarrhea).
  • The patient has been living in households where there have been sick and febrile persons with strongly suspected or diagnosed Ebola.
  • The patient has participated in the care of ill and febrile patients with high suspicion or diagnosis of ebola, or has been in contact with body fluids (including unprotected intercourse), tissue or deceased patient.
  • Healthcare personnel, laboratory personnel or other personnel who have come into contact with body fluids, tissue or body of human or animal with highly suspected or established ebola.
  • The patient has previously been classified as a patient with a “mild risk” for Ebola and then developed organ failure and/or signs of bleeding without any other explanation.

Patients who are considered to have a “high risk” of Ebola are isolated at the ID clinic. Individuals who contact a healthcare facility from the home by telephone and where a suspicion of a “high risk” of Ebola arises during the call are referred to the ID clinic. The attending physician determines where the patient should be placed to minimize the risk of infection. The patient should be transported by ambulance. While awaiting the ambulance transport to the ID clinic, the patient is cared for in a separate room and must not be allowed to stay or be allowed to pass waiting rooms.

If a patient is deemed to have a “high risk” for Ebola, urgent contact from the ID clinic is made with the county council’s infection protection physician for advice on assessment and continued treatment. The information is also made available to the Public Health Agency and the National Board of Health and Welfare.

Verified ebola case

If infection with the ebola virus is verified, the patient is moved to the isolation unit, where there are specially adapted premises and experiences in caring for patients with highly-contagious serious infections for a long time.

Patients Without Clinical Symptoms

Mild risk, definition

Temporary contact with a febrile Ebola-sick person without other symptoms in connection with, for example:

  • Stay in the same waiting room
  • Travel by the same bus
  • Serving as a receptionist in a hospital/care facility

To those who are deemed to have mild risk of being exposed to Ebola, a calming message is given, but the individual is recommended to check the temperature twice daily for 21 days after the last possible exposure and to seek appropriate care immediately if the temperature goes up to 38.6 °C or if symptoms of illness occur.

High risk, definition

Patient who has had close contact (<1 m) face to face without adequate protective equipment with Ebola patient who coughs, or vomits, or has bleeding, or diarrhea, or has skin or mucosal contact including needlesticks, with body fluid or tissue from Ebola-infected patient.

Persons who are at high risk for transmission of ebola virus should be offered care at the nearest ID clinic without delay and the infection control physician should be informed.

Transport of patient samples

All sample transport, both externally and within organizations, shall be carried out by well-trained personnel in accordance with regulations and local guidelines for the transport of dangerous goods. When transporting within your own organization, it is very important that the recipient is warned and that these samples are handed in personally, and that information is shared regarding suspicion of Ebola.

External transport must always take place with a courier approved for the purpose, which means a transport company with a permit to transport dangerous goods, after the samples have been packed in accordance with special regulations.

Further Reading