What is the case fatality rate of hantavirus?

Case fatality rates vary dramatically by virus strain and clinical syndrome. HPS, caused by New World hantaviruses including Sin Nombre, Andes, Choclo, and Juquitiba viruses, carries a 35–40% mortality rate even with intensive care. HFRS, caused by Old World hantaviruses, is generally less lethal: Puumala virus (Northern Europe) has fatality rates near 0.1%, Seoul virus around 1%, Dobrava-Belgrade virus up to 12%, and Hantaan virus (East Asia) up to 15%. Survival depends heavily on early ICU admission. In HPS, survival exceeds 60% when intensive supportive care — including mechanical ventilation and ECMO — is started before cardiopulmonary collapse.