Andes virus: the South American hantavirus that can spread person-to-person

Andes virus is a hantavirus species circulating in South America. It is hosted by the long-tailed pygmy rice rat (Oligoryzomys longicaudatus) and causes hantavirus pulmonary syndrome (HPS) with case-fatality ratios reported between 25% and 40% depending on the cluster. What makes Andes virus distinctive is the documented capacity for human-to-human transmission, especially during the prodromal and early cardiopulmonary phases. This has been described in family clusters, healthcare contacts, and — as of 2026 — passengers on a cruise ship that originally departed from Ushuaia, Argentina. Other hantaviruses such as Sin Nombre virus in North America have not shown this property. Genetic lineages of Andes virus include Andes Sout (southern Argentina/Chile), Andes Centro, Andes North, and Lechiguanas, with subtle differences in virulence and host association. Diagnosis relies on RT-PCR or virus-specific serology, both available in regional reference laboratories such as Malbrán (Argentina) and ISP (Chile). Public health response in suspected Andes virus clusters includes contact tracing, isolation of symptomatic individuals, droplet precautions in healthcare settings, and supportive care in intensive-care units when respiratory distress develops.