Building the legacy of Ebola: Survivors, health systems, and a blueprint for research and development
- Frequently asked questions on Ebola virus disease vaccine
- Ebola Response Report 2016 (2.1 MB)
- Knowlege resources for Ebola (PDF, 555.11 kB)
- Ebola virus disease (EVD), formerly known as Ebola haemorrhagic fever, is a severe, often fatal illness in humans.
- The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.
- The average EVD case fatality rate is around 50%. Case fatality rates have varied from 25% to 90% in past outbreaks.
- The first EVD outbreaks occurred in remote villages in Central Africa, near tropical rainforests. The 2014–2016 outbreak in West Africa involved major urban areas as well as rural ones.
- Community engagement is key to successfully controlling outbreaks. Good outbreak control relies on applying a package of interventions, namely case management, infection prevention and control practices, surveillance and contact tracing, a good laboratory service, safe burials and social mobilisation.
- Early supportive care with rehydration, symptomatic treatment improves survival. There is as yet no licensed treatment proven to neutralize the virus but a range of blood, immunological and drug therapies are under development.
Reports from 2019
Reports from 2018
- Declaration of the end of the ninth EVD outbreak in Bikoro Health Zone, Équateur Province: 25 July 2018
Reports from 2017
There are six known species of Ebola virus. The 2014–2016 outbreak in West Africa was the first to be documented in that part of the continent. It was the largest and most complex to date, with more cases and deaths than all other outbreaks combined. It also spread between countries, starting in Guinea then moving across land borders to Sierra Leone and Liberia. Related cases occurred in Italy, Spain and the United States.
In the early stages of the disease, Ebola symptoms are flu-like, so misdiagnosis is easy. Other symptoms, such as diarrhoea and vomiting that occur in the early stages, are non-specific and can be misdiagnosed as another disease common to these regions, such as malaria. In some cases (20%), both internal and external bleeding (for example, oozing from the gums, or blood in the stools) occur. For most, the bleeding is internal, as the Ebola virus attacks and damages the capillaries: the small blood vessels in the body. Some experts have described it as ‘dying from a thousand internal cuts.’
Definitive diagnosis can be obtained in a properly equipped laboratory. WHO and partners have supported the setting up of diagnostic capacities in countries at risk of Ebola outbreaks as part of their preparedness programmes.
There is no effective treatment. Treatment is supportive and may include providing intravenous fluids and balancing electrolytes, maintaining oxygen status and blood pressure, replacement of lost blood and clotting factors, and treating other infections if they occur for maintenance of organ function, and combating haemorrhage and shock.
In the 2018-2019 Ebola outbreak in the Democratic Republic of the Congo, the first-ever multi-drug randomized control trial was conducted to evaluate the effectiveness and safety of drugs used in the treatment of Ebola patients. They were used under an ethical framework developed in consultation with experts in the field and the Democratic Republic of the Congo. Preliminary results were promising for two of the drugs randomised in decreasing mortality. Both were monoclonal antibodies mAb114 and REGN-EB3.
An experimental Ebola vaccine known as rVSV-ZEBOV proved highly effective against the deadly virus in a major trial in Guinea in 2015. It was used in response to the current outbreak in the Democratic Republic of the CongoDRC as recommended by the WHO’s Strategic Advisory Group of Experts on Immunization (SAGE) and using ring vaccination as the main vaccination strategy. Ring vaccination is where contacts and contacts of known Ebola cases are vaccinated.
Further information on EVD vaccines is available at : https://www.who.int/emergencies/diseases/ebola/frequently-asked-questions/ebola-vaccine
Recovery may begin between seven to 14 days after first symptoms. Death, if it occurs, typically occurs between six to 16 days from first symptoms and is often due to low blood pressure from fluid loss. In general, bleeding often indicates a worse outcome, and blood loss may result in death. People are often in a coma towards the end of life.
A number of medical complications have been reported in people who recovered from Ebola, including mental health issues. To address these needs, a dedicated programme can be set up to care for people who have recovered from Ebola. Most survivors will develop antibodies against Ebola that are thought to last at least ten years, but it is unclear whether they are immune to additional infections.