The Argentine government is investigating whether passengers who fell ill and died aboard a Dutch-flagged cruise ship had contracted a rare hantavirus while still in Argentina, as the country grapples with a doubling of infections from the rodent-borne disease. Three travelers—a 70-year-old Dutch man, his 69-year-old wife, and a German woman—died after the MV Hondius set sail from Ushuaia toward Antarctica on April 1. All three tested positive for the Andes strain of hantavirus, according to Argentine health authorities and the World Health Organization.
The deaths aboard the vessel come as Argentina has recorded 101 hantavirus infections since June 2025, roughly twice the number reported in the same period a year earlier, the country’s health ministry said Tuesday. The fatality rate in the most recent year reached nearly 33 percent, well above the five-year average of 15 percent.
The virus, which can incubate for one to eight weeks, is primarily spread by inhaling contaminated rodent excrement, urine or saliva. The Andes strain is the only hantavirus known to transmit from person to person, although such transmission remains rare, the WHO has said. The agency added that the overall risk to the public is low.
Cruise ship outbreak sparks international traceback
Authorities in Argentina are working to pinpoint where the infected passengers traveled before they embarked. The Dutch couple, according to the WHO, spent time as tourists in Ushuaia and traveled to other parts of Argentina and Chile before boarding the ship. The vessel remained docked for weeks at the southern Argentine port city, which sits in the province of Tierra del Fuego—a region that has never registered a hantavirus case, health officials noted.
The leading hypothesis within Argentina’s government is that the Dutch couple contracted the virus during a birdwatching outing in Ushuaia, two researchers familiar with the investigation told the Associated Press. They spoke on condition of anonymity because they were not authorized to discuss the matter publicly while the inquiry continues. Authorities are also tracing the couple’s movements through remote forested slopes of Patagonia, where some hantavirus concentrations have been documented.
Argentina said Wednesday it was sending genetic material from the Andes virus and testing equipment to Spain, Senegal, South Africa, the Netherlands and the United Kingdom to aid detection efforts.
Climate change supercharges rodent populations
Health experts in Argentina are linking the surge in hantavirus to accelerating climate shifts. Rising temperatures and erratic rainfall patterns are expanding the habitats of the rodents that carry the virus, they say.
“Climate change entered Argentina and as Argentina became tropicalized it brought many problems, like dengue, zika, chikungunya and yellow fever,” said Hugo Pizzi, a prominent Argentine infectious disease specialist. “That change may have favored a greater flowering and greater amount of seeds that are the food of these mice. There is no doubt that as time goes on, it is like it spreads more and more.”
Raúl González Ittig, a genetics professor at the National University of Córdoba and a researcher for the state science agency CONICET, explained the ecological chain: periods of heavy rain produce more vegetation, which attracts rodents; dry spells then drive them out of their normal habitats in search of food and water, increasing human exposure.
“When there is an increase in precipitation, the availability of food increases, and that leads to an increase in rodent populations,” Ittig said. “If there is an infected rodent, it increases the possibility of transmitting the virus to other rodents” and eventually to humans.
Cases move north, rural areas vulnerable
The geographic footprint of hantavirus in Argentina has shifted dramatically. While infections were once largely confined to the southern reaches of Patagonia, 83 percent of cases are now found in the country’s north, according to the health ministry.
The ministry issued an alert in January after several deadly clusters, including one in Buenos Aires province, the most populous part of the country. Rural hospitals are often poorly equipped to recognize the disease, and residents can be unaware of the danger until it is too late.
Daisy Morinigo and David Delgado described how their 14‑year‑old son Rodrigo came down with fever and body aches. Doctors in the town of San Andrés de Giles examined the boy, sent him home with ibuprofen and told him to rest. When his breathing worsened, the family rushed him to intensive care on January 1. He died barely two hours after a hantavirus test came back positive.
“I wouldn’t wish this pain on anyone in the world,” Delgado said.
Because early symptoms mimic the fever and chills of a common flu, the disease often goes unrecognized in its initial stages, a pattern that González Ittig said makes hantavirus “very dangerous,” especially among travelers who might dismiss their symptoms.