The Pathogenesis of Ebola Virus Disease∗

For almost 50 years, ebolaviruses and related filoviruses have been repeatedly reemerging across the vast equatorial belt of the African continent to cause epidemics of highly fatal hemorrhagic fever. The 2013-2015 West African epidemic, by far the most geographically extensive, most fatal, and longest lasting epidemic in Ebola's history, presented an enormous international public health challenge, but it also provided insights into Ebola's pathogenesis and natural history, clinical expression, treatment, prevention, and control. Growing understanding of ebolavirus pathogenetic mechanisms and important new clinical observations of the disease course provide fresh clues about prevention and treatment approaches. Although viral cytopathology and immune-mediated cell damage in ebolavirus disease often result in severe compromise of multiple organs, tissue repair and organ function recovery can be expected if patients receive supportive care with fluids and electrolytes; maintenance of oxygenation and tissue perfusion; and respiratory, renal, and cardiovascular support. Major challenges for managing future Ebola epidemics include establishment of early and aggressive epidemic control and earlier and better patient care and treatment in remote, resource-poor areas where Ebola typically reemerges. In addition, it will be important to further develop Ebola vaccines and to adopt policies for their use in epidemic and pre-epidemic situations.