“Hantavirus is most commonly spread through contact with rodent urine, droppings, [and] saliva in the case of a bite,” says Dr. Carla McWilliams, chief of infectious disease, quality and safety for Cleveland Clinic Weston Hospital. “Though human-to-human transmission has been reported, it is considered to be quite rare.”
There are no specific treatments for hantavirus, but hospitals can offer supportive care, including breathing assistance and ventilation to help with severe respiratory symptoms. Starting care as early as possible is important to improve chances of recovery, the CDC says.
Did the hantavirus outbreak originate on the cruise ship?
International health officials believe that the initial infection of hantavirus occurred before passengers boarded the ship in Argentina on April 1. “With the timing of the incubation period of hantavirus, which can be anywhere from one to six weeks, our assumption is that they were infected off the ship, perhaps doing some activities there,” Kerkhove of WHO said.
“Cases 1 and 2 had traveled in South America, including Argentina, before they boarded the cruise ship on 1 April 2026,” WHO’s alert says. “The extent of passenger contact with local wildlife during the voyage, or prior to boarding in Ushuaia remains undetermined.”
However, person-to-person transmission cannot fully be ruled out, even though it’s exceedingly rare with hantavirus. “We do believe that there may be some human-to-human transmission that’s happening among the really close contacts,” Kerkhove said, citing the deceased husband and wife and some of the ill passengers who shared cabins.
Should travelers be concerned about hantavirus continuing to spread?
“Person-to-person transmission of hantavirus is very rare, and known to occur with just one strain,” says Dr. Daniel Kuritzkes, senior physician in the Division of Infectious Diseases at Mass General Brigham.
That strain, called the Andes hantavirus, is endemic to both Chile and Argentina. Although the vessel originally departed from Argentina, “it’s too soon to draw conclusions from what happened on board this ship,” McWilliams says.
Despite the fact that WHO is still investigating whether person-to-person transmission occurred on board, it is still a rare phenomenon and isn’t likely to continue off the ship.
Additionally, close contact, rather than casual contact, appears to be an important factor in human transmission of the virus, Kuritzkes notes, citing one study that found respiratory droplets—rather than aerosols—are likely to be behind rare cases of human transmission. “The significance being that droplets settle quickly and are less likely to result in infection of people who just happen to be in the same room,” Kuritzkes says.
Overall, experts expect the current situation to remain isolated to the cruise ship. In past instances of person-to-person spread of hantavirus, quarantine promptly led to the control of the outbreak, according to Kuritzkes. “There is a very low likelihood that the current outbreak will lead to a more generalized epidemic,” he says.
Should travelers take any special precautions if they’re visiting Argentina or South America?
Travelers shouldn’t feel the need to cancel trips to South America or take any measures beyond normal safety precautions. “There’s no reason for people to be concerned about travel to Argentina, but people should be cautious about visiting places where rodents might be nesting,” says Kuritzkes. “People staying at typical hotels, eating in restaurants, and visiting typical tourist attractions most likely have no or minimal risk of acquiring hantavirus.”
Travelers should continue to follow basic health guidelines, such as avoiding areas with poor sanitation practices as well as areas with visible rodents, McWilliams advises. “For prevention, we know that having adequate sanitation practices, adequate ventilatory systems, ensuring that rodents are exterminated and eliminated is all very key and crucial to preventing any transmission,” she says.
