Ebola virus disease (EVD)

Ebola virus disease (Ebola or EVD) is a rare but serious illness that can be life-threatening. It is caused by a group of viruses that produce viral hemorrhagic fever (VHF), and it has also been known as Ebola hemorrhagic fever.

Fruit bats are thought to be the natural host of Ebola viruses. From time to time the virus also causes outbreaks among other animals, such as chimpanzees, gorillas, monkeys and forest antelope. People usually become infected through close contact with the blood, organs or other bodily fluids of infected animals, whether alive or dead.

Once a person is infected, the virus can pass from person to person through contact with bodily fluids, including blood and waste products.

Ebola is not present everywhere in the world. Many outbreaks have been recorded since the virus was first identified, with the first occurring in 1976 in Sudan and the Democratic Republic of Congo. Between 2014 and 2016 a large outbreak affected Guinea, Liberia and Sierra Leone in West Africa, though active transmission in those areas later ended. A further outbreak was identified in the Democratic Republic of Congo in 2018. Updates on current outbreaks are available from the World Health Organization (WHO).

Symptoms#

People with Ebola are not thought to be infectious until they develop symptoms. Symptoms usually appear within 2 to 21 days of infection, and most commonly between 8 and 10 days. Early symptoms can include fever, headache, muscle and joint aches, weakness, vomiting, diarrhea and a raised rash.

As the illness progresses, further problems may develop, including:

• malfunction of the liver
• malfunction of the kidneys
• internal or external bleeding
• progression to multi-organ failure
• death

Risk of infection#

The risk of catching Ebola is extremely low unless there has been direct exposure to the blood or bodily fluids of an infected person or animal, alive or dead. This includes unprotected sexual contact with someone who has had a confirmed diagnosis of Ebola, for up to three months after they have recovered. People who live in or travel to affected areas may be at higher risk.

If you are traveling in an affected country and feel unwell, seek medical attention immediately. If you have returned from an affected country and feel unwell, seek medical help straight away and tell your doctor where you have been, and whether you may have been in contact with someone who has had Ebola.

Diagnosis and prevention#

Ebola is diagnosed by finding genetic material from the virus in a person’s blood, throat swab or urine. There is currently no widely available vaccine to prevent Ebola, although trials of a potential vaccine are underway.

If you are traveling to an affected area, avoid direct exposure to the blood or bodily fluids of an infected person or animal, alive or dead. If you are traveling to an affected area to work or volunteer in a healthcare setting, seek advice beforehand and make sure you are fully informed about infection control procedures and recommendations.

Reporting#

Ebola is a notifiable disease. A single case of Ebola, or of any viral hemorrhagic fever, would be considered an outbreak and requires immediate clinical and public health control measures. Health authorities must be contacted immediately if a health professional suspects a case.

Key points#

• Ebola virus disease (Ebola or EVD) is a rare disease that causes severe symptoms and can be life-threatening
• It belongs to a family of viruses that cause viral hemorrhagic fever (VHF)
• People with Ebola are not known to be infectious until they develop symptoms
• Later symptoms can include malfunction of the liver and kidneys and internal or external bleeding
• People who live in or travel to affected areas may be at risk of infection

Where to get help#