Ebolavirus

Ebolavirus is a genus of enveloped, filamentous, negative-sense RNA viruses in the family Filoviridae, within the order Mononegavirales. Members of this genus cause Ebola virus disease (EVD) in humans and nonhuman primates. The genus currently includes six recognized species: Zaire ebolavirus, Sudan ebolavirus, Taï Forest ebolavirus, Bundibugyo ebolavirus, Reston ebolavirus and Bombali ebolavirus.

Natural reservoirs are believed to be fruit bats, with spillover to humans and other animals occurring through contact with infected animals or their fluids. Human-to-human transmission occurs mainly via direct contact with blood or bodily fluids of infected persons, including during and after death; transmission can be facilitated in health care settings without appropriate infection control.

Clinical presentation typically begins with sudden fever, fatigue, muscle pain, and headache, followed by vomiting, diarrhea, rash, impaired kidney and liver function, and in some cases hemorrhagic manifestations. Case fatality rates vary by species and outbreak, historically highest with Zaire ebolavirus. Reston ebolavirus has caused disease in nonhuman primates and, in rare human infections, mild or no symptoms; Bombali ebolavirus has not been clearly linked to human disease to date.

Diagnosis is by nucleic acid testing (RT-PCR) or antigen detection in blood; virus isolation is restricted to high-containment laboratories. Prevention relies on rapid public health measures, infection control, and vaccination where appropriate. The rVSV-ZEBOV vaccine (Ervebo) provides protection against Zaire ebolavirus and is used in ring vaccination strategies during outbreaks.

Treatment is primarily supportive care, including fluids and electrolyte management. Two monoclonal antibody therapies, Inmazeb (REGN-EB3) and Ebanga (ansuvimab-zykl), have been approved to improve survival in certain EVD cases, and experimental antivirals and therapies continue to be evaluated.