Hantavirus hemorrhagic fever with renal syndrome (HFRS) is a group of clinically similar illnesses caused by species of hantaviruses from the family Hantaviridae, in the order Bunyavirales. It is also known as Korean hemorrhagic fever and epidemic hemorrhagic fever. The species that cause HFRS include Hantaan orthohantavirus, Dobrava-Belgrade orthohantavirus, Saaremaa virus, Seoul orthohantavirus, Puumala orthohantavirus and other orthohantaviruses. It is found in Europe, Asia, and Africa. Of these species, Hantaan River virus and Dobrava-Belgrade virus cause the most severe form of the syndrome and have the highest morbidity rates. When caused by the Puumala virus, it is also called nephropathia epidemica. This infection is known as sorkfeber in Swedish and myyräkuume in Finnish (vole fever). In Norway, it is called musepest (mouse plague).
Both hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS) appear to be immunopathologic, and inflammatory mediators are important in causing the clinical manifestations.