The World Health Organization confirmed on Wednesday May 6, 2026, that the specific strain of hantavirus responsible for killing three people aboard the MV Hondius and infecting at least five others is the Andes virus, the only type of hantavirus in the world known to transmit from person to person.
At the same time, a new case emerged in Switzerland, bringing the total number of cases to eight and extending the outbreak beyond the ship’s passenger list to a continent the vessel never visited.
The Andes virus confirmation changes the nature of this story. Hantavirus transmitted by rodent contact is tragic and concerning.
Hantavirus that may be moving between human beings, specifically the one strain that is capable of doing so, requires a different kind of response and raises different questions about how the outbreak began and how far it might spread.
The answers so far provide significant reassurance. But the questions themselves are genuinely new.
What Has The World Health Organization Confirmed?
The Andes strain was identified through collaborative laboratory work between health authorities in South Africa, Switzerland, Senegal and Argentina.
Two of the confirmed cases on the ship, the Dutch woman who died in Johannesburg and the British man who remains in intensive care there, both tested positive for the Andes strain. The Swiss case confirmed Wednesday is also the Andes strain.
This specific identification matters because of what distinguishes the Andes virus from every other hantavirus.
There are dozens of hantavirus strains. They are found on every inhabited continent. Most of them cannot transmit from person to person at all, they pass to humans exclusively through contact with infected rodents or their droppings, urine or saliva, and the chain of transmission ends there.
An infected person does not infect another person. The virus has no human-to-human pathway.
The Andes virus, found primarily in Argentina and Chile, is the exception. In previous outbreaks, most notably in Argentina in 2018, which produced 34 cases and 11 deaths, limited transmission between people with prolonged close contact has been documented and confirmed.
A husband and wife. People sharing a cabin. The kind of contact that involves sustained physical proximity over extended time, not the casual proximity of shared public spaces.
WHO’s Maria Van Kerkhove, director of epidemic and pandemic preparedness and prevention, addressed the transmission question at a news conference Wednesday.
“We do believe there may be some human-to-human transmission happening among the really close contacts, the husband and wife, people who’ve shared cabins,” she said. She was also direct about what this is not. “This is not a virus that spreads like flu or like COVID. It’s quite different.”
The Theory Of How It Started
The working hypothesis that WHO is currently investigating centers on the Dutch couple who were among the first to become ill.
The husband, a 70-year-old Dutch man, died aboard the ship on April 11. His 69-year-old wife died approximately two weeks later in South Africa on April 26. Both tested positive for the Andes strain.
Importantly, both had traveled in Argentina, including Ushuaia, where the ship departed on April 1, 2026, before boarding the MV Hondius.
Van Kerkhove said WHO is working on the assumption that the couple may have contracted the Andes virus while exploring wildlife in Argentina, before they ever stepped onto the ship.
Ushuaia sits at the tip of Patagonia, Andes virus territory, a region where the virus circulates in rodent populations and where human exposure through wildlife activity is possible.
If the couple brought the virus aboard from Argentina, the subsequent cases, the British man in the ICU in Johannesburg, the German national who died aboard the ship on May 2, the three others with mild symptoms, and now the Swiss case, would represent the downstream consequences of that initial exposure.
Some through rodent contact at the same locations, some potentially through the close-contact human transmission the Andes strain is capable of.
Angela Rasmussen, a virologist at the University of Saskatchewan, offered important context for interpreting what is happening.
“People really do need to understand that there are different degrees of person-to-person transmission,” she said. The Andes virus can transmit between people.
That transmission requires prolonged close contact. It is not airborne in the way that respiratory viruses like influenza or COVID-19 are airborne.
Being near an infected person in a hallway or a dining room is not the same exposure level as sharing a bed or a cabin for weeks.
The Switzerland Case
The eighth confirmed case arrived Wednesday from a direction no one was tracking. A man returned to Switzerland after being a passenger on the MV Hondius and subsequently developed symptoms.
He consulted his doctor, underwent testing, and was confirmed positive for the Andes strain. He is being treated at University Hospital Zurich in isolation.
The Swiss Federal Office of Public Health confirmed that he “returned to Switzerland after traveling on the cruise ship on which there were a number of hantavirus cases.” Swiss authorities have not specified when exactly the patient was aboard the Hondius.
His case is both alarming and instructive. Alarming because it confirms that passengers left the ship carrying the virus before the outbreak was identified and before anyone was monitoring departures.
At least one infected person traveled home to Europe, went through airports, and arrived at their destination before anyone was looking for them. Contact tracing for his flight has been initiated.
Instructive because he sought medical care, was identified, and has been isolated. The monitoring system, while imperfect, worked for this case. He is being treated.
His contacts are being traced. South Africa separately identified 62 contacts from its cases, including flight crew and healthcare workers, who are being monitored. None of those 62 contacts have been diagnosed with hantavirus so far.
How Long Will The Ship Remain Stranded?
Three people were evacuated from the MV Hondius on Wednesday, lifted off the ship anchored off Praia, the capital of Cape Verde, and transferred to medical care. WHO Director-General Dr. Tedros Adhanom Ghebreyesus confirmed the evacuations.
One of the three evacuees is the ship’s doctor, who had been ill and was originally expected to travel to the Canary Islands.
His condition improved enough that he is now being transferred directly to the Netherlands.
A second evacuee is associated with the German national who died aboard the ship on May 2. The third is a critically ill crew member.
The ship itself remains anchored off Cape Verde. The Spanish national government had agreed to receive the vessel at a Canary Islands port for full disinfection and passenger processing.
The regional government of the Canary Islands, led by President Angel Clavijo, rejected that plan.
“Without having information, I cannot allow them to enter the Canary Islands, because we don’t know what we are dealing with,” Clavijo told Spanish radio station Onda Cero.
The result is that nearly 150 passengers and crew remain aboard a ship with no confirmed port destination.
WHO representative Ann Lindstrand acknowledged Wednesday that the Andes virus’ incubation period can run up to eight weeks. meaning passengers could theoretically need to remain aboard for that long while authorities confirm no new cases are developing.
Passengers have been advised to wear masks, practice social distancing and limit close contact with others. The vibe on the ship is being described by those aboard as calm rather than panicked.
Passenger Kasem Hato said: “People are taking the situation seriously but without any panic, trying to keep social distancing and wearing masks to be safe.”
Passenger Jake Rosmarin, whose video plea from the ship circulated widely earlier in the week, put the crew’s and passengers’ core need plainly, “All we want right now is to feel safe, to have clarity, and to get home.”
The Major Health Risk Of Hantavirus
Every major health authority that has addressed the MV Hondius outbreak has communicated the same assessment. The risk to the general public is low, and this is not a global health threat on the scale of COVID-19 or influenza.
Hans Kluge, WHO’s regional director for Europe, was direct. “There is no need for panic or travel restrictions.”
The Andes virus does not spread through the air the way respiratory viruses do. It does not spread through casual contact. The largest outbreak of the Andes strain in recorded history, Argentina 2018, produced 34 cases and 11 deaths.
Fewer than 900 total hantavirus cases have been recorded in the United States across 30 years of surveillance. WHO estimates 10,000 to 100,000 global hantavirus cases annually across all strains, a fraction of what even a mild influenza season produces.
What makes this outbreak unusual and scientifically significant is the setting, a closed community at sea, a strain with human-to-human transmission capability, and the fact that at least one infected passenger has already dispersed into the European population.
All of those factors justify the level of monitoring and contact tracing currently underway. None of them justify the level of alarm that words like “human-to-human transmission” can trigger when stripped of context.
The Andes virus is deadly to those it infects, roughly 38 percent of people who develop severe respiratory symptoms die. It is not easily transmitted. It requires close, sustained contact to move between people.
It does not replicate efficiently in the way that pandemic pathogens do. What is happening on the MV Hondius is a medical emergency for the people aboard it and a public health concern requiring careful monitoring. It is not, according to every expert who has addressed it, a wider threat.
If it is not easily transmitted, how did one person infected at least 6 more people, besides his wife and the doctor? We don’t know his relationship with those people but I assume he didn’t share the same cabin with them, so transmission occurred in other circumstances that doesn’t necessarily involve close, sustained contact