What is the difference between HPS and HFRS?

The two clinical syndromes caused by hantaviruses split cleanly along New World / Old World lines.

HPS — Hantavirus Pulmonary Syndrome

• Where: the Americas — North, Central and South.
• Pathogens: Sin Nombre, Andes, Bayou, Black Creek Canal, Choclo, Laguna Negra, and related New World species.
• Reservoirs: sigmodontine rodents (deer mice, cotton rats, rice rats).
• Pathophysiology: diffuse capillary leak in the lungs, leading to acute respiratory failure.
• CFR: 30–40% for ANDV / SNV; lower for Choclo, Laguna Negra.

HFRS — Hemorrhagic Fever with Renal Syndrome

• Where: Eurasia — East Asia, Russia, the Balkans, Fennoscandia, Central Europe.
• Pathogens: Hantaan, Puumala, Seoul, Dobrava-Belgrade, Tula.
• Reservoirs: murid rodents (Apodemus mice, voles, Rattus rats).
• Pathophysiology: capillary leak with renal cortex and medulla involvement; classic five-phase course (febrile, hypotensive, oliguric, polyuric, convalescent).
• CFR: < 0.5% for Puumala, 1–2% for Seoul, 10–15% for Hantaan and Dobrava.

Both syndromes share an early prodromal phase of fever, severe muscle aches and headache. The divergence comes in week two: HPS patients decompensate respiratorily; HFRS patients move into oliguric renal failure with bleeding manifestations. Treatment is supportive in both; ribavirin shows early-treatment benefit for HFRS but not HPS.