Hantaviruses cause hundreds of thousands of cases of haemorrhagic fever with renal syndrome (HFRS) in Europe and Asia each year.
Andes virus, associated with Oligoryzomys longicaudatus, causes HPS in the northern Patagonian regions of Argentina and Chile (19). Another hantavirus, Oran virus, also causes HPS and is apparently associated with the same rodent species in extreme northern Argentina (19). However, the population of O. longicaudatus in northern Argentina appears to be disjunct from the population that follows the Andean cordillera and includes northwestern Patagonia (20). Careful taxonomic and distributional studies are required to determine if these disjunct rodent populations represent distinct species and to define the potential HPS-endemic areas associated with each virus.
Hantaviral disease was thought to be rare or absent in the United States, although three cases of mild HFRS associated with rat-borne Seoul virus had been described in 1994. In 1993, the discovery of hantavirus pulmonary syndrome (HPS), which rapidly kills approximately half of those infected, surprised public health officials and virologists in the United States. The causative agent, Sin Nombre virus (SNV), is hosted by the deer mouse Peromyscus maniculatus, and the disease syndrome markedly differs from HFRS. Since 1993, at least 20 additional hantaviruses have been isolated from rodents throughout the Americas; about half are known human pathogens, including Oran virus, Andes virus, New York virus, Monongahela virus, Bayou virus, Black Creek canal virus Juquitiba virus, Laguna Negra virus, HU39694 virus and Lechiguanas virus.