Andes hantavirus outbreak from cruise MV Hondius traced to Patagonia rodent

The Andes hantavirus (ANDV) is naturally carried by the long‑tailed pygmy rice rat (Oligoryzomys longicaudatus), a wild rodent endemic to Argentina and Chile. The virus can be transmitted to humans through inhalation of contaminated urine, feces or saliva and is notable for documented human‑to‑human spread.

In May 2026 an outbreak among passengers of the polar cruise ship MV Hondius resulted in several deaths and a handful of confirmed cases, prompting alerts from the World Health Organization and follow‑up monitoring in France and other countries.

A field team from Argentina’s National Institute of Infectious Diseases Carlos Malbrán has captured about 150 rodents around Ushuaia and surrounding natural areas to determine whether the long‑tailed rat is present and carrying ANDV. So far none of the captured specimens have been identified as the primary reservoir, and laboratory analysis is ongoing to compare any viral strains found with those from infected passengers.

Researchers warn that climate‑driven changes in Patagonian ecosystems could expand the habitat of rodent reservoirs, potentially increasing the risk of future hantavirus spillover events.