Ebolavirus

Ebolavirus is a genus of negative-sense, single-stranded RNA viruses in the family Filoviridae, with filamentous virion morphology. Several species exist (e.g., Zaire ebolavirus, the most virulent and cause of the 2014 West African outbreak). Transmission occurs through direct contact with blood, secretions, organs, or other bodily fluids of infected humans or animals (fruit bats are suspected natural reservoirs); nosocomial spread and unsafe burial practices are important amplifiers. Pathophysiology involves viral replication in monocytes, macrophages, and dendritic cells, triggering massive cytokine release ('cytokine storm'), endothelial dysfunction, increased vascular permeability, and impaired coagulation leading to disseminated intravascular coagulation (DIC). This results in the hallmark hemorrhagic manifestations (petechiae, ecchymoses, mucosal bleeding) along with fever, severe fatigue, myalgia, vomiting, diarrhea, and in later stages, multi-organ failure and shock. Incubation period is 2-21 days. Diagnosis is via RT-PCR detecting viral RNA, especially during symptomatic phase; antigen-capture ELISA and IgM/IgG serology are also used. Case fatality rates range from 25-90% depending on strain and supportive care quality. Management is primarily supportive: aggressive fluid/electrolyte repletion, hemodynamic support, and treatment of complications; two FDA-approved monoclonal antibody therapies (Inmazeb and Ebanga) target the viral glycoprotein for Zaire ebolavirus. The rVSV-ZEBOV vaccine (Ervebo) is approved for prevention of Zaire ebolavirus disease. Strict infection control (PPE, isolation) is critical to prevent healthcare worker infection and outbreak propagation. High-yield Step associations: filovirus, hemorrhagic fever, cytokine storm, DIC, high mortality, West/Central Africa outbreaks, fruit bat reservoir.