What Is Hantavirus and Why Is the Andes Strain So Dangerous — Evergreen Guide to Symptoms Transmission Prevention and the 2026 Cruise Ship Outbreak
Hantavirus is a family of rodent-borne viruses that can cause severe and potentially fatal respiratory disease in humans. The Andes strain which caused the 2026 MV Hondius cruise ship outbreak that killed three people is uniquely dangerous among hantaviruses because it can — in rare cases — spread from person to person through prolonged close contact. Most hantavirus strains cannot do this. There is no approved vaccine or widely available antiviral treatment for hantavirus pulmonary syndrome. This explainer covers what hantavirus is how it spreads why the Andes strain is different who is at risk and what the 2026 outbreak revealed about our preparedness for rare rodent-borne pathogens.