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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 Zaire species of Ebolavirus was the causative agent of the 2014-2016 epidemic in West Africa [5], where there were nearly 29,000 total cases (suspected, probable, or confirmed), of which more than 15,000 were laboratory confirmed. During this epidemic, there were approximately 11,000 deaths [6]; based on the total estimated case count, the overall case fatality rate was approximately 40 percent. In earlier outbreaks in Central Africa caused by the same virus species, case fatality rates reached 80 to 90 percent.

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".)


During the nearly 40 years since the first recognized Ebola outbreaks in Zaire and Sudan in 1976 through the beginning of the 2014-2016 epidemic in West Africa, several publications have described the clinical and laboratory features of the disease [1,8,9]. That information has been supplemented by many patient series from Ebola treatment units in West Africa and case reports of patients treated in the United States and in Europe (table 1) [10-15].

Although most features of Ebola virus disease in the West African epidemic matched earlier descriptions, patients differed in two respects:


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