Ebola disease

Ebola disease is a rare but severe illness, caused by a virus belonging to the genus orthoebolavirus of the Filoviridae family. Death rates have varied from 25% to 90% in past outbreaks.

Six species of orthoebolaviruses have been identified to date, with three known to cause large outbreaks:

• Ebola virus (EBOV) causing Ebola virus disease (EVD)
• Sudan virus (SUDV) causing Sudan virus disease (SVD)
• Bundibugyo virus (BDBV) causing Bundibugyo virus disease (BVD).

The animal reservoir of the viruses is unknown, but current evidence suggests that fruit bats (Pteropodidae) may be a host.

The symptoms of Ebola disease can be sudden and can include:

• fever
• fatigue
• muscle pain
• headache and sore throat.

These can be followed by:

• vomiting
• diarrhoea
• rash
• internal and external bleeding.

The time interval from infection to onset of symptoms ranges from 2 to 21 days. People are only infectious once they develop symptoms.

Even when people have developed Ebola disease-like symptoms, only a laboratory test can confirm whether the cause is Ebola.

Ebola disease symptoms often appear suddenly and require early care by trained clinicians.

Because of the similarity of symptoms, it can be difficult to clinically distinguish Ebola disease from other infectious diseases such as malaria, typhoid fever, dengue or Marburg virus disease.

Therefore, it is essential that people with Ebola disease-like symptoms seek advice immediately from a health-care provider. Testing is the first step in identifying accurately what is causing illness and is essential for providing the right treatment. Early testing and treatment save lives and protect community and family members, including local health and care workers.

Ebola disease most commonly spreads from person to person via exposure to blood or other body fluids (mostly through faeces, vomit, sweat and saliva) of an infected person, alive or deceased. This occurs when the virus enters a body through broken skin or mucous membranes (such as the eyes, nose or mouth), most often while someone is caring for a patient or touching the body of someone who has died from the disease.

It is also spread by touching or handling objects that have been contaminated with the body fluids of a sick person or someone who has died from Ebola disease.

In rare instances, transmission from a male survivor to his sexual partner has been documented. This is because the virus can persist for some time in the semen of some male survivors after they recover from the disease.

In case of an Ebola disease outbreak, people can protect themselves by taking specific measures that reduce the risk of infection. These include:

• avoiding physical contact with individuals who are suspected of or confirmed to have Ebola disease;
• refraining from handling the bodies of people who had symptoms of Ebola disease and have died, without appropriate protective measures; and
• washing hands regularly, applying best practices recommended by local authorities on hand washing.

During an outbreak, those at higher risk of infection are:

• health and care workers in close contact with patients;
• caretakers, family members or others in direct physical contact with infected people; and
• mourners who have direct physical contact with bodies during funerals or burial rituals.

A person with Ebola-like symptoms (fever, headache, muscle aches, headache, vomiting, diarrhoea) who has been in contact with living or dead people suspected to have had Ebola or has travelled to an area known to have cases of Ebola virus disease should seek medical care immediately.

Community health and care workers are among the first to detect new illnesses within a community, raise alerts, and refer those who are ill to the health facility.

Health-care workers and community health workers are at greater risk of infection when they:

• are not wearing correct personal protective equipment (PPE); and
• are not applying infection prevention and control (IPC) measures when caring for patients or managing bodies of the deceased.

Since the symptoms of Ebola disease are similar to many other common illnesses, community health and care workers may not immediately use appropriate infection prevention and control measures to protect themselves.

There are two approved treatments for adults and children with Ebola virus disease (EVD), which are themonoclonal antibodies mAb114 (ansuvimabTM) and REGN-EB3 (InmazebTM).

Building on these successes, potential new treatments are being evaluated for other orthoebolaviruses, but these have not yet been fully tested.

If you or a loved one tests positive for Ebola disease, early supportive care at a designated treatment centre is essential and can improve the chance of survival. Care is free of charge and includes rehydration, provision of proper nutrition and the management of symptoms.

WHO does not advise families or communities to care for people with Ebola disease at home. People with symptoms should seek care at a health facility. Early supportive care at a designated treatment centre is essential and can improve the chance of recovery.

If a person dies at home with suspicions of Ebola disease, the community and family members should refrain from handling or preparing the body for burial. Community or family members should immediately get in contact with local health authorities to perform a safe and dignified burial of the deceased person in accordance with the family’s wishes.

WHO does not recommend trade or movement restrictions such as lockdowns or quarantines in areas affected by Ebola disease.

However, travel of close contacts of Ebola disease cases should be minimized or postponed wherever possible to protect people who may be exposed to the virus during travel and to avoid spreading of the virus.

If travel of a contact is necessary, it should be discussed and supervised by the public health authorities for them to ensure the appropriate follow-up in the host area.