Frequently Asked Questions
Evidence-based answers about Ebola virus disease, sourced from WHO, CDC, and MSF guidelines.
Ebola virus disease (EVD) is a rare and often fatal illness in humans caused by infection with one of the Ebola virus species. The virus is transmitted to humans from wild animals and spreads in the human population through direct contact with blood, secretions, organs or other bodily fluids.
Ebola spreads through direct contact (broken skin or mucous membranes) with blood or body fluids of a person who is sick with or has died from EVD. It is NOT transmitted through air, water, or food. Ebola is not contagious during the incubation period — only once symptoms appear.
The case fatality rate (CFR) varies by outbreak and strain. Historically, CFR ranges from 25% to 90%. With modern supportive care in treatment centres, CFR in recent outbreaks has been closer to 40–66%. Early treatment significantly improves survival odds.
Yes. rVSV-ZEBOV (brand name Ervebo, by Merck) is WHO-prequalified and approved for Zaire ebolavirus, the most common strain. It is used under a ring vaccination strategy. No approved vaccine exists yet for Sudan or other Ebola species.
Two monoclonal antibody treatments — Inmazeb (atoltivimab/maftivimab/odesivimab) and Ebanga (ansuvimab) — are FDA-approved for Zaire ebolavirus. Supportive care (IV fluids, electrolytes, oxygen) also significantly improves outcomes.
The incubation period is 2 to 21 days, with an average of 8–10 days. During incubation, an infected person shows no symptoms and is NOT contagious. This is the window for contact tracing and ring vaccination.
No. Ebola does not spread through the air under normal circumstances. It requires direct contact with infected bodily fluids. This is why Ebola outbreaks, while deadly, do not spread as widely or rapidly as respiratory diseases.
Both are species of ebolavirus causing EVD but differ genetically. Zaire ebolavirus has caused the most outbreaks (including all DRC outbreaks and the 2014–2016 West Africa epidemic). Sudan ebolavirus caused the Uganda 2022 outbreak. The approved vaccine and treatments only cover Zaire ebolavirus.
The risk outside active outbreak areas is very low. Ebola does not spread easily and all known outbreaks have been contained in Africa. Travel-associated cases outside Africa have been extremely rare. Monitor WHO/CDC travel health notices if travelling to affected regions.
The natural reservoir host of Ebola is believed to be fruit bats of the Pteropodidae family. The virus is introduced into the human population through close contact with blood, secretions, organs or other bodily fluids of infected animals such as fruit bats, chimpanzees, gorillas, or forest antelopes.