Ebola diseases (EBOD) are rare but severe and often fatal viral diseases that affect humans and other primates. There are six species in the genus Ebolavirus, three of which (Bundibugyo, Sudan and Zaire) have previously caused large outbreaks. Ebolaviruses are transmitted to people from wild animals such as fruit bats, porcupines and non-human primates, and spread through direct contact 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.
The first cases of Ebola diseases were detected in two concomitant outbreaks in Sudan and in Zaire (now the Democratic Republic of the Congo) in 1976. Outbreaks have since occurred in the Democratic Republic of the Congo, Gabon, Guinea, Liberia, Republic of the Congo, Sierra Leone, Sudan and Uganda. Imported cases have also been found in Mali, Nigeria, Senegal and South Africa. The 2014–2016 outbreak in West Africa was the largest and most complex ever recorded.
Ebola case fatality rates have varied from 25% to 90% in past outbreaks. With currently available effective treatment, patients have a significantly higher chance of survival if treated early and given supportive care.
