What Is Hantavirus and How Does It Spread? The Andes Strain Explained

Hantaviruses form a family of RNA viruses found worldwide, particularly in rural areas with high rodent populations. According to the U.S. Centers for Disease Control and Prevention, the virus typically reaches humans through contact with the urine, droppings or saliva of infected rodents, or by inhaling dried particles. Symptoms begin with fever, muscle pain and fatigue, progressing in severe cases to acute respiratory failure.

Hantavirus pulmonary syndrome, common in the Americas, has a fatality rate of about 38 percent according to the CDC. In Europe, infections more often present as a milder kidney-focused illness. The Andes strain, identified on the cruise ship, circulates mainly in Chile and Argentina and is the only hantavirus type for which person-to-person transmission, through close household contact or kissing, has been documented in a small number of cases.

The World Health Organization notes there is no approved antiviral treatment or vaccine for hantavirus, and survival depends on early diagnosis and intensive supportive care. Health experts recommend ventilating spaces before cleaning rodent nests and using gloves and masks. Authorities say the cruise ship outbreak could yield important new data on how the Andes strain transmits in confined settings.