Hantavirus has rarely commanded international attention — until now. On May 2, 2026, health authorities reported a deadly outbreak of Andes virus, a type of hantavirus, among passengers and crew aboard a cruise ship in the Atlantic Ocean. The event has renewed public interest in a pathogen that most people have never heard of.
Hantaviruses are a group of viruses carried by rodents that can cause severe disease in humans. People usually get infected through contact with infected rodents — or their urine, droppings, or saliva. In the Americas, hantaviruses can cause hantavirus cardiopulmonary syndrome (HCPS), a severe respiratory illness with a case fatality rate as high as 50%. In Europe and Asia, they instead cause hemorrhagic fever with renal syndrome (HFRS), which primarily affects the kidneys and blood vessels.
What makes the current outbreak particularly alarming is the specific strain involved. Andes virus is the only type of hantavirus known to spread person-to-person — a trait that sets it apart from most hantavirus strains. This spread is usually limited to people who have close contact with an ill person, including exposure to saliva, respiratory secretions, or other body fluids.
The disease’s global footprint is broader than many realize. Worldwide, it is estimated that between 10,000 and over 100,000 infections occur each year, with the largest burden in Asia and Europe. Meanwhile, hantavirus cases in Argentina have nearly doubled in the past year, with the country recording its highest number of infections since 2018 — a trend experts attribute to climate change.
Treatment options remain frustratingly limited. There are no specific treatments or vaccines for the Andes virus, and early supportive medical care — focused on close monitoring and managing respiratory, cardiac, and kidney complications — is currently the primary means of improving survival.
For now, public health officials stress that the overall risk to the general public remains extremely low, but the cruise ship outbreak serves as a vivid reminder that rare pathogens can emerge in unexpected places.
