Topline
World Health Organization officials are pointing to an almost 8-year-old outbreak of the Hantavirus Andes variant in Argentina—the same strain responsible for a deadly outbreak on a cruise ship sailing for the Canary Islands—as a hopeful example for controlling the disease’s spread and keeping it from becoming a “large epidemic.”
Health personnel assisting patients onto a boat from the cruise ship MV Hondius on May 6, 2026.
AFP via Getty Images
Key Facts
Dr. Abdirahman Mahamud of the WHO on Thursday said the cruise ship situation is “similar” to an outbreak seen in Epuyén, Argentina in 2018 and 2019, in which the Andes strain (the only known hantavirus variant that can transmit person-to-person) was introduced the human population by a single infected person.
That person attended a party before displaying symptoms, according to a WHO description of the outbreak, and six people from the same party then became symptomatic before continuing to pass the disease to others.
After 18 cases were confirmed, public health officials forced people with confirmed cases to quarantine and encouraged self-isolation of possible contacts, measures a later study said “likely curtailed further spread.”
In total, there were 34 confirmed Andes infections and 11 deaths and the outbreak is considered to be the largest documented human-to-human transmission event ever.
The Argentine outbreak was the first time sustained person-to-person transmission of a hantavirus was spurred from a super-spreader event, infectious disease researchers reported, which were previously known to spur spread of diseases like Ebola and coronavirus.
Crucial Quote
“We are in a similar situation right now: A cluster in a confined space with close contact. Does that mean it will spread to the rest of the world?” Mahamud asked “If we follow public health measures… we can break this chain of transmission and it doesn’t need to be a large epidemic.”
Big Number
8 to 31 days. That was the incubation period for Andes infections during the Argentine outbreak. Dr. Tedros Ghebreyesus, director of the WHO, on Thursday said it can be up to six weeks before those infected show symptoms.
Key Background
Health officials are scrambling to contract trace anyone who may have come in contact with passengers aboard a cruise ship, upon which an Andes outbreak has already caused three deaths. The MV Hondius left Ushuaia, Argentina en route to the Canary Islands on April 1 and, 11 days later, a 70-year-old Dutch man died on board. Cruise officials have said that at the time they thought he’d died of natural causes and did not know he had a contagious infection. Weeks later, his wife died after disembarking the boat with her husband’s body and a third person, a German national, died aboard the boat on May 2. Several other people have started showing symptoms and, in total, there have been five lab-proven hantavirus cases and three additional suspected cases. All those who developed symptoms aboard the ship have either died or been medically evacuated, and WHO officials on Thursday said nobody still onboard is symptomatic. The ship is currently sailing for the Canary Islands, where Spanish officials say they will be allowed to disembark by May 11. Oceanwide Expeditions, operator of the cruise ship, has said at least 29 passengers from 12 countries disembarked the ship and went home after the death of the first passenger on board (before officials knew of the outbreak). Health workers are trying to trace them and encourage self-isolation among those passengers, who hail from Canada, Denmark, Germany, Netherlands, New Zealand, Switzerland, Sweden, Singapore, Saint Kitts and Nevis, Turkey, United Kingdom and the United States. Officials have said they believe the hantavirus outbreak originated on a bird-watching outing that took the deceased Dutch couple to a landfill, where they may have been exposed to rodents carrying the virus before boarding the ship. Follow updates on the situation here.