The country where lethal hantavirus cases are on the rise. Experts blame climate change

Argentina’s Lethal Hantavirus Outbreak Rises: Climate Change Suspected

The country where lethal hantavirus cases – Argentina has become the focal point of a growing hantavirus concern, with infections nearly doubling over the past year. This surge has led to 32 fatalities this year, the highest mortality rate since 2018. Health authorities are now investigating whether climate change has played a role in this alarming trend, particularly as a recent outbreak on the MV Hondius cruise ship has drawn attention to the virus’s expanding reach.

Tracing the MV Hondius Connection

The MV Hondius, which departed from Ushuaia, Argentina’s southernmost port, on April 1, is currently heading to Spain’s Canary Islands. Its arrival in Granadilla, Tenerife, is expected by early Sunday. The cruise’s passengers are under scrutiny as the vessel has been linked to a major outbreak. While the origin of the virus remains unclear, the Andes strain—known for human-to-human transmission through direct contact—has emerged as a key suspect.

Argentina’s health ministry reported 101 confirmed cases this season, compared to 57 in the same period in 2024. The lethality rate has also increased by 10 percentage points, with deaths climbing sharply. These figures, however, do not yet include the outbreak on the MV Hondius, which has added complexity to the analysis of the disease’s spread.

Climate Change and Ecosystem Shifts

Environmental shifts, driven by climate change and human activity, are now being scrutinized as a critical factor in the virus’s proliferation. Experts suggest that changing ecosystems have allowed rodents—carriers of hantavirus—to thrive in new areas. “Climate change and habitat expansion are creating ideal conditions for the virus to emerge beyond its traditional zones,” the ministry noted, emphasizing the role of ecological changes.

Recent extreme weather patterns, such as prolonged droughts and heavy rainfall, have altered food and shelter availability for the long-tailed mouse, a primary carrier in Argentina and Chile. “Rodents adapting to these shifts may explain the spike in infections,” said Eduardo López, an infectious disease specialist. His insights highlight how ecological transformations are amplifying the risk.

Regional Spread and Risk Zones

While hantavirus was historically confined to Patagonia, this season’s cases have shifted to the central region, with Buenos Aires province reporting the most infections at 42. The ministry identified four key risk areas: the Northwest (Salta, Jujuy, Tucumán), Northeast (Misiones, Formosa, Chaco), Center (Buenos Aires, Santa Fe, Entre Ríos), and South (Neuquén, Río Negro, Chubut). These regions, known for their humid climates and dense vegetation, are now central to the outbreak’s spread.

The Dutch couple who died after traveling across Argentina visited both Misiones in the Northeast and Neuquén in the South, crossing into Chile and Uruguay. Their movements have raised questions about how the virus is spreading beyond its traditional habitats. Health officials warn that the virus’s reach is no longer limited to remote areas, with urban and rural regions increasingly at risk.

Additional Drivers of the Outbreak

Climate change is not the sole contributor to the rise in hantavirus cases. Forest fires have also played a role, displacing both humans and wildlife into new environments. “Wildfires force populations into closer proximity with infected rodents, increasing transmission risks,” said Roberto Debbag, vice president of the Latin American Society of Vaccinology. Tourism trends further complicate the picture, as travelers may inadvertently carry the virus to previously low-risk areas.

Environmental degradation has allowed rodents to expand their range, creating a perfect storm for new outbreaks. “Rising temperatures and shifting weather patterns disrupt rodent populations, making them more active and widespread,” Debbag added. This convergence of factors has led to a situation where the virus is now a growing threat across diverse regions of the country.