HPS vs HFRS: The Two Faces of Hantavirus Disease

Hantaviruses cause two distinct clinical syndromes. Knowing which one you might encounter depends on where you live or travel. This article compares them on every relevant axis: strain, geography, target organ, severity, and treatment.

Quick answer

Hantavirus pulmonary syndrome occurs in the Americas, caused mainly by Sin Nombre and Andes viruses. Hemorrhagic fever with renal syndrome occurs in Europe and Asia, caused mainly by Hantaan, Seoul, Puumala, and Dobrava-Belgrade viruses. HPS attacks the lungs and is highly lethal. HFRS attacks the kidneys with severity that varies by strain.

Side by side

Why the names are confusing

The naming reflects geography and clinical features rather than a logical taxonomy. Sin Nombre is Spanish for “no name” because researchers initially refused to name the virus after the affected community. Hantaan is named after the Hantan River in Korea. Puumala is named after a town in Finland. The disease names follow the dominant clinical pattern in each region.

The umbrella term hantavirus disease covers both syndromes. WHO and CDC use the syndrome names in their public materials. ECDC uses hantavirus infection as the umbrella term in European surveillance.

Pathology in brief

Both syndromes share a mechanism: hantaviruses infect endothelial cells lining small blood vessels. The infection itself does not destroy the cells, but the immune response to the infection causes massive vascular leak.

In HPS, the leak is concentrated in pulmonary capillaries. Plasma floods alveoli, causing the rapid respiratory failure that makes Sin Nombre virus dangerous.

In HFRS, the leak affects renal microcirculation, retroperitoneal vessels, and other tissues. Kidney injury is the dominant feature, but bleeding from mucosal surfaces and into tissues can occur in severe cases.

Severity by strain

Hantaan virus and Dobrava-Belgrade virus cause the most severe HFRS, with case fatality rates between 5 and 15 percent. Hantaan dominates in China, North and South Korea, and parts of Russia. Dobrava is found in the Balkans and parts of Central Europe.

Seoul virus, found worldwide because of brown rat distribution, causes a milder HFRS with mortality around 1 to 2 percent.

Puumala virus, dominant in Northern and Central Europe, causes nephropathia epidemica. Most patients recover, and mortality is typically below 0.5 percent. The illness is unpleasant but rarely lethal.

Sin Nombre virus is the most lethal hantavirus described. The CDC reports an HPS case fatality rate around 38 percent in the United States. Andes virus is comparable in severity and has the additional feature of person to person transmission.

What this means for travelers

Travelers visiting endemic regions face low absolute risk because human exposure depends on rodent contact and proximity. The exception is rural and back country travel:

• Cabins and rustic accommodation in the western United States, especially the southwest, carry HPS risk
• Hiking and ecotourism in southern Argentina and Chile carry Andes virus risk
• Forested areas in Northern Europe in late spring and summer carry Puumala risk during peak vole years
• Rural areas in East Asia carry Hantaan virus risk, especially during fall and winter

Practical mitigation: avoid sleeping in rodent-infested cabins, do not handle wild rodents, follow safe cleanup procedures if you have to clear a space, and seek medical attention with a clear exposure history if you develop fever and muscle pain after returning home.