Ebola Virus Disease

Ebola virus disease (EVD), formerly known as Ebola haemorrhagic fever, is a severe, often fatal illness in humans. Ebola virus disease is caused by four different strains of Ebola virus; these viruses infect humans and nonhuman primates. The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission. The virus family Filoviridae includes three genera: Cueva virus, Marburg virus, and Ebola virus. Within the genus Ebola virus, five species have been identified: Zaire, Bundibugyo, Sudan, Reston and Taï Forest. The first three, Bundibugyo ebola virus, Zaire ebola virus, and Sudan ebola virus have been associated with large outbreaks in Africa. The virus causing the 2014–2016 West African outbreak belongs to the Zaire ebola virus species.

Ebola is introduced into the human population through close contact with the blood, secretions, organs or other bodily fluids of infected animals such as chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines found ill or dead or in the rainforest. Ebola then spreads through human-to-human transmission via direct contact (through broken skin or mucous membranes) with the blood, secretions, organs or other bodily fluids of infected people, and with surfaces and materials (e.g. bedding, clothing) contaminated with these fluids.

Symptoms of Ebola Virus Disease (EVD) are treated as they appear. When used early, basic interventions can significantly improve the chances of survival. These include:
  • Providing fluids and electrolytes (body salts) through infusion into the vein (intravenously).
  • Offering oxygen therapy to maintain oxygen status.
  • Using medication to support blood pressure, reduce vomiting and diarrhea and to manage fever and pain.
  • Treating other infections, if they occur.

Recovery from EVD depends on good supportive care and the patient’s immune response. Those who do recover develop antibodies that can last 10 years, possibly longer. It is not known if people who recover are immune for life or if they can later become infected with a different species of Ebola virus. Some survivors may have long-term complications, such as joint and vision problems.