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Clinical manifestations and diagnosis of Ebola virus disease

Mike Bray, MD, MPH
Daniel S Chertow, MD, MPH
Section Editor
Martin S Hirsch, MD
Deputy Editor
Jennifer Mitty, MD, MPH


The family Filoviridae consists of three genera: Ebolavirus and Marburgvirus (which are among the most virulent pathogens of humans) [1-3], and Cuevavirus, which has only been detected in bats in Spain [4]. The genus Ebolavirus consists of five species: Zaire, Sudan, Bundibugyo, Tai Forest, and Reston.

The Zaire species was discovered in 1976, and has been responsible for some dozen outbreaks in the Democratic Republic of the Congo (DRC) and neighboring countries, with case fatality rates often approaching 90 percent. In 2014, the Zaire virus appeared in West Africa [5], producing an epidemic in Liberia, Guinea, and Sierra Leone that took more than two years to bring under control. There were nearly 29,000 total cases (suspected, probable, or confirmed), of which more than 15,000 were laboratory confirmed, and the overall case fatality rate was approximately 40 percent [6].

The Sudan species was also first recognized in 1976, and in four outbreaks in Uganda and Sudan, case fatality rates have averaged 50 percent. The Bundibugyo species has been responsible for small outbreaks in Uganda and the adjacent DRC, while the Ivory Coast virus has caused one nonfatal case. The Reston virus does not cause disease in humans.

Epidemics of Ebola virus disease are generally thought to begin when an individual becomes infected through contact with the body fluids of an infected animal. Once the individual becomes ill or dies, the virus spreads to others who come into direct contact with their blood or other body fluids. On rare occasions, Ebola virus disease has resulted from accidental laboratory infections [7], and there is concern that the virus might be used as an agent of bioterrorism.

The clinical manifestations and diagnosis of Ebola virus disease will be reviewed here. The epidemiology, pathogenesis, treatment, and prevention of this disease are discussed elsewhere. (See "Epidemiology and pathogenesis of Ebola virus disease" and "Treatment and prevention of Ebola virus disease".)

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Literature review current through: Nov 2017. | This topic last updated: Dec 04, 2017.
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