History
Patagonia Origins: The Discovery of Andes Virus
Three decades before the world's first hantavirus cruise-ship outbreak, the southern Andes produced something new. The story is worth knowing because every current question about Andes virus traces back to it.
The first recognised cluster of hantavirus disease in Argentina occurred in late 1995 in the Patagonian town of El Bolsón. The cases were severe respiratory illnesses in young, otherwise healthy people. The local clinicians thought, reasonably, of influenza. The pattern of clustering, though, was wrong for influenza.
What the clinicians noticed
Within a few weeks, the El Bolsón cluster had several troubling features. Multiple members of single households fell ill. A physician who had cared for two of the cases developed the same syndrome. Another investigator from Buenos Aires, sent to study the outbreak, became a patient. These were not the patterns of a pure rodent-borne disease.
Naming the virus
Virologists Ricardo Wainberg, Paula Padula and colleagues at the Instituto Nacional de Enfermedades Virales Humanas (INEVH) in Pergamino isolated and sequenced the responsible agent. It was a previously undescribed hantavirus, distinct from Sin Nombre. They named it Andes virus, after the geographic feature that frames the affected region.
By 1996, the team had published the case for person-to-person transmission. It was contentious at the time - every existing model of hantavirus said this should not happen - but the epidemiology was difficult to argue with. The hantavirus paradigm shifted.
The reservoir
Andes virus's primary reservoir is Oligoryzomys longicaudatus, the long-tailed pygmy rice rat. It is widespread in the temperate forests and grasslands of southern Argentina and Chile. As with deer mice further north, infected rice rats appear healthy and shed virus in urine and droppings throughout their lifespan.
From 1995 to 2026
In the three decades since El Bolsón, Andes virus has produced steady, low-level disease across Patagonia. The 2018–19 Epuyén outbreak - also in Argentina - produced 34 confirmed cases and 11 deaths, with clear evidence of super-spreader dynamics. Each outbreak has refined understanding; each has confirmed that this virus is unusual but not unmanageable.
What the MV Hondius situation does is bring the virus, for the first time, into a setting that traditional public-health surveillance for Patagonia was never designed to cover: a multinational vessel arriving in Europe after weeks at sea. The science is not new. The geography of the problem is.
Editorial note
This article is intended as public information, not individual medical advice. If you are concerned about your symptoms, contact a qualified healthcare professional. We update outbreak reporting as new primary-source information becomes available.