USHUAIA, Argentina (AP) 鈥� Argentine investigators searching for the source of a on a cruise last month were trapping rodents in the forests surrounding the on Tuesday, with the aim of detecting the possible presence of the rat-borne virus in an area previously thought unaffected.
The scientists, wearing bright blue gloves and surgical masks, checked the 150 box traps they had set out the previous night, dropping dead rats into black plastic bags that they hoisted into pickup trucks bound for a makeshift lab where they said they’d draw blood samples.
Tuesday鈥檚 rat-trapping marks the start of fieldwork within Argentina’s wider investigation into the origin of the contagion that , killing three people, sickening several others and setting off a global scramble to trace passengers and their close contacts.
Argentine investigators trudging through mud to retrieve the dead rats declined to speak to journalists about their work. The state-backed Malbr谩n Institute, Argentina鈥檚 leading research center for infectious diseases, said the team would repeat the routine for the next three days before returning with the samples to the institute鈥檚 main Buenos Aires laboratory to test for . Testing could take up to one month, but officials were tight-lipped about further details.
鈥淭hey were able to capture what was expected,鈥� said Mart铆n Alfaro, the spokesperson for the local health ministry of Tierra del Fuego.
The effort comes almost two weeks after the Argentine Health Ministry first announced it would send the team from the Malbr谩n Institute to Ushuaia. The popular tourism destination where the cruise departed 鈥� famed for its location at the 鈥渆nd of the world鈥� 鈥� serves as the main gateway to the Antarctic.
Questions surround Argentina’s investigation
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 鈥� a Dutch couple passionate about birds 鈥� didn’t visit during the window in which it is believed they got infected.
The Dutch tourists concluded a sprawling road trip across and Argentina in late March with a few days of bird-watching and trekking in Ushuaia before boarding the ship April 1.
Health authorities here have fiercely rejected the national government鈥檚 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 .
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 鈥渃olilargo” that runs rampant through the forests of northern .
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.
Adamant that tourism-dependent Tierra del Fuego isn’t the source of the cruise ship outbreak, health authorities here say they welcome 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 鈥� the national park and the wooded hillsides overlooking Ushuaia鈥檚 main pebble beach.
鈥淭he province has never done this kind of testing before,鈥� Alfaro said. 鈥淚t’s important that we rule out the possibility of transmission occurring here.鈥�
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 and human encroachment.
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