Argentina on Friday said it was expanding its investigation into the origins of the hantavirus outbreak that struck an Atlantic cruise ship last month, sending scientists to trap and test rats in the western province of Mendoza while lab results are pending from the southernmost city of Ushuaia.
Argentine authorities said biologists from the U.S. Centers for Disease Control and Prevention were joining the mission next week in Mendoza.
The rare outbreak on the MV Hondius was caused by the Andes hantavirus, a disease carried by rodents endemic to Argentina and Chile and the only hantavirus thought to be able to spread between people in some cases.
Reconstructing the chain of transmission is difficult work, and Argentine authorities say it may never be possible to pinpoint exactly where the first known victims — a Dutch couple who died in April — contracted the virus before boarding the cruise in Ushuaia. But experts say getting to the bottom of the outbreak will offer valuable information about how the rare virus spread and carry important lessons for management of the disease.
As repatriated cruise passengers from more than 20 countries have disembarked and entered specialized quarantine centers, epidemiologists are examining the 11 confirmed hantavirus cases, including the schedules of the three people killed, to better understand the chain of transmission.
Argentine scientists are working to retrace the path of the Dutch tourists, believing that the original source of the onboard virus to be the man’s exposure to rodent droppings or urine during their monthslong trip across Argentina and Chile before the ship’s departure The typical incubation period before symptoms appear is around three weeks but can extend up to eight.
Shortly after news of the outbreak emerged, Argentina’s Health Ministry identified Ushuaia as a possible source of the contagion and last month sent investigators from the Malbran government research institute to collect rodent samples in various wooded areas around the city.
Local authorities in the tourism-dependent city of Ushuaia, famed for its location at “the end of the world,” have angrily disputed that the virus originated there. While the Andes hantavirus infects a few dozen people every year in the Patagonian region of Argentina further north, it has never been detected in Ushuaia or the wider archipelago of Tierra del Fuego.
The Health Ministry said Friday that it’s still awaiting lab results from those tests to determine whether the couple contracted the virus there.
On Friday, the ministry said specialists from Malbran, together with U.S. counterparts at the CDC, were preparing to test rodents for the hantavirus in the city of Malargüe, Mendoza from June 8-12.
A spokesperson for the Malbran Institute confirmed that the Dutch couple visited Malargüe as they drove through the winemaking region of Mendoza to the northeastern province of Misiones during the last leg of their trip in Argentina.
The head of Malbran, Claudia Perandones, met with CDC investigators in Argentina on Friday to discuss the operation, which she said would involve teams in extensive protective equipment taking blood samples from dead rodents and transferring the material to the main laboratory in Buenos Aires for testing. Authorities have said test results could take up to a month.
The World Health Organization has made clear that, given the low risk of transmission, the hantavirus will not become a pandemic threat.
Still, the Andes hantavirus has raised concerns around the world due to its mortality rate, as high as 30%, and the current lack of treatment and vaccines.
