Argentine investigators were trapping rodents in the forests surrounding Ushuaia on Tuesday as part of a state-backed search for the source of a deadly hantavirus outbreak linked to the cruise ship MV Hondius, which killed three people, sickened several others and triggered a global scramble to trace passengers and their close contacts.
Who Gets Put Under the Microscope
Scientists wearing bright blue gloves and surgical masks checked 150 box traps they had set out the previous night, dropping dead rats into black plastic bags and hoisting them into pickup trucks bound for a makeshift lab. There, they said they would draw blood samples. The fieldwork marked the start of an investigation into whether the rat-borne virus was present in an area previously thought unaffected.
The team came from the state-backed Malbrán Institute, Argentina’s leading research center for infectious diseases. The institute said the scientists would repeat the routine for the next three days before returning with the samples to its main Buenos Aires laboratory to test for hantavirus. Testing could take up to one month, but officials were tight-lipped about further details.
Martín Alfaro, the spokesperson for the local health ministry of Tierra del Fuego, said, “They were able to capture what was expected.” The effort came almost two weeks after the Argentine Health Ministry first announced it would send the team from the Malbrán Institute to Ushuaia.
What the Authorities Say They’re Looking For
The popular tourism destination where the cruise departed, famed for its location at the “end of the world,” serves as the main gateway to the Antarctic. Health authorities in Tierra del Fuego said they welcomed a broader objective of the investigation: figuring out if their province has hantavirus at all at a time of global warming.
They said the scientists were trapping rats in two areas where the colilargo subspecies proliferates — the national park and the wooded hillsides overlooking Ushuaia’s main pebble beach. Alfaro said, “The province has never done this kind of testing before.” He added, “It’s important that we rule out the possibility of transmission occurring here.”
The hantavirus has never been recorded in Ushuaia or the wider archipelago of Tierra del Fuego. But provincial officials further north in Patagonia, where the hantavirus is endemic, insist that the first known victims of the outbreak — a Dutch couple passionate about birds — didn’t visit during the window in which it is believed they got infected.
The Dutch tourists concluded a sprawling road trip across Chile and Argentina in late March with a few days of bird-watching and trekking in Ushuaia before boarding the ship April 1. Health authorities rejected the national government’s initial hypothesis that the chain of infections on the cruise began when the couple visited an Ushuaia landfill. They have both since died, complicating the efforts of Argentine investigators to retrace their path through the country with the aim of determining where they contracted the virus.
The Virus, the Rats, and the Limits of Control
Found throughout southern Chile and Argentina, the Andes virus may be able to spread between people in rare cases. Most clusters of the Andes virus, experts say, emerge from exposure to air contaminated with the feces and urine of the long-tailed pygmy rice rat known as the colilargo that runs rampant through the forests of northern Patagonia.
The colilargo itself has no presence across the Strait of Magellan in Tierra del Fuego, which is believed to be too cold and isolated for the rat. But a subspecies can be found in the forests around Ushuaia, and scientists have never examined whether it can transmit the hantavirus.
The number of hantavirus cases has increased in recent years in Argentina, a trend scientists attribute to colilargos vastly increasing their range as a result of climate change and human encroachment. That wider pattern sits behind the current scramble: a public health apparatus trying to catch up after the fact, moving samples between field traps, a makeshift lab and Buenos Aires while officials offer little beyond cautious statements and a month-long testing window.