Hantavirus Outbreak Investigation in Argentina
Officials and health experts in Argentina are urgently trying to determine if a deadly hantavirus outbreak is originating from their country, which has affected passengers on an Atlantic cruise. This health crisis comes as Argentina experiences an increase in hantavirus cases, a rise that local public health researchers believe is linked to the accelerating impacts of climate change. Argentina, the starting point for the Antarctic cruise, is recognized by the World Health Organization as having the highest rate of this rare, rodent-borne disease in Latin America.
Experts explain that rising temperatures are expanding the virus’s reach. As conditions warm and ecosystems shift, rodents that carry hantavirus are thriving in more areas. This typically results in humans being exposed to the virus through contact with rodent droppings, urine, or saliva.
Hugo Pizzi, an infectious disease specialist in Argentina, remarked, “Argentina has become more tropical due to climate change, leading to various disruptions. We’ve seen issues like dengue and yellow fever, as well as new plants that increase food sources for mice, allowing their populations to grow.” He indicated concern that hantavirus is progressively spreading.
On Tuesday, the Argentine Health Ministry reported 101 hantavirus infections since June 2025—this number is about double what was noted during the same period last year.
The Andes virus, a strain of hantavirus found in South America, can lead to a severe lung condition known as hantavirus pulmonary syndrome. Last year, nearly a third of those infected died, a notable increase from the average mortality of 15% in the previous five years. The virus typically spreads through inhaling contaminated droppings, and while human-to-human transmission is rare, it is possible, according to the WHO. The Andes strain is the only one documented to transmit between humans.
Passengers aboard the MV Hondius tested positive for the Andes virus, prompting Argentina to send genetic samples and testing equipment to several countries, including Spain and the UK, to aid in detection.
Investigation Into Infection Sources
Argentine authorities are working to trace where the infected passengers traveled before boarding the Dutch-flagged cruise ship in Ushuaia, located in southern Argentina. Once they confirm travel itineraries, they plan to identify close contacts and monitor them to curtail further transmission.
The WHO reported that the first death on board occurred on April 11, involving a 70-year-old Dutch man, followed by his wife’s death on April 26 and a German woman who died on May 2.
The virus can incubate for one to eight weeks, making it hard to determine if the passengers contracted it before leaving Argentina, during a stop at a remote island, or while on the ship.
Tierra del Fuego, the province where the ship docked, has never recorded a hantavirus case. Prior to boarding, the Dutch couple explored Ushuaia and traveled to various locations in Argentina and Chile, according to the WHO.
Authorities believe the couple may have contracted the virus during a bird-watching excursion in Ushuaia. Investigators have also been tracing their movements in the forests of Patagonia, where several infections are found.
As early symptoms can mimic flu-like issues, “tourists might dismiss it as a simple cold, which is particularly concerning,” remarked Raul González Ittig, a genetics professor and researcher.
Impact of Climate Change on Rodent Populations
Argentina has recently faced significant droughts and unexpected heavy rainfall, creating wild weather patterns attributed to climate change. Such variability has fostered conditions for hantavirus to flourish. For instance, dry periods can drive animals to find food and water elsewhere, while heavy rains can boost vegetation growth that attracts rodents.
Ittig pointed out that increased precipitation leads to a rise in food availability, sparking rodent population growth, which in turn raises the possibility of hantavirus transmission. Although hantavirus cases were once largely confined to Patagonia, now 83% of reported cases are occurring in the northern regions of Argentina.
Early Warnings Issued
This year, the Health Ministry alerted the public regarding several deadly outbreaks, particularly in Buenos Aires province. In rural areas that are often under-equipped, many residents were caught off guard. For instance, Daisy Morinigo and David Delgado initially thought their 14-year-old son had the flu when he developed fever and body aches. After being sent home from a local doctor’s visit, Rodrigo’s condition worsened, leading to a rush to intensive care where he died shortly after testing positive for hantavirus.
“I wouldn’t wish this pain on anyone,” Delgado shared, underscoring the intense sorrow of their family’s experience.
