[Viral hemorrhagic fevers: Pathogenesis, epidemiology and clinical manifestations]

Viral hemorrhagic fevers are severe infections caused by selected enveloped RNA viruses from the families Filoviridae, Arenaviridae, Flaviviridae, and the order Bunyavirales. Their pathogenesis is characterized by early failure of antiviral immunity, high viremia, endothelial dysfunction, capillary leak, and coagulopathy. Clinically, they initially present as non-specific febrile illnesses, but may progress to organ dysfunction, hemorrhagic manifestations, or shock. Laboratory findings commonly include early leukopenia, thrombocytopenia, and elevated liver enzymes. The current epidemiological situation shows considerable regional variability. For many of these infections, transmission via vectors, zoonotic spread, or nosocomial transmission plays a significant role. In Europe, the risk of most hemorrhagic fevers remains low but, not negligible. Continuous surveillance of imported cases, together with access to high-quality laboratory testing, effective infection control including prevention of nosocomial spread, and vigilance in febrile patients with relevant epidemiological exposure, are essential. Limited therapeutic and vaccination options highlight the need for further research and international collaboration, as well as preparedness for the potential importation of these infections.