Belgrade virus, a cause of hemorrhagic fever with renal syndrome in the Balkans, is closely related to Dobrava virus of field mice.

Belgrade virus is a recently described hantavirus that causes severe hemorrhagic fever with renal syndrome (HFRS) in people living in various parts of the Balkan Peninsula. Nucleotide sequencing of the G2-encoding region in the medium (M) segment of the viral genome, reverse transcribed and amplified by the polymerase chain reaction, revealed the Belgrade virus to be substantially different from Hantaan virus and other major serotypes of hantavirus but identical to Dobrava virus, a virus isolated from a field mouse (Apodemus flavicollis) in Slovenia. Belgrade virus may be an important cause of HFRS in the Balkan Peninsula, extending north toward the Alps. It poses a special danger to humans who have close contact with field rodents.