Hantavirus on cruise ship: How the outbreak was identified almost a month after passenger died

A rare hantavirus outbreak crisis unfolded on a cruise ship that sailed from Argentina toward Antarctica and then across the Atlantic Ocean over several weeks.

It then stopped on the way near remote islands after the health of passengers and crew members deteriorated, according to information from the cruise operator, the World Health Organisation (WHO), and ship-tracking data.

As per the information, nearly a month passed between a 70-year-old Dutch man falling ill and dying in the South Atlantic and laboratory tests in South Africa, which is over 3,500 kilometres (2,174 miles) away, confirming the hantavirus infection.

In total, three passengers have died. One remains in intensive care in a South African hospital, and three other passengers remaining on the cruise ship have developed symptoms and are awaiting evacuation.

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According to reports, around 150 passengers and crew members from 23 nations were on the deadly ship, which is currently stationed off the West African coast.

Hantavirus is not a single pathogen but a group of viruses belonging to a broader family known as hantaviruses, which are carried by rodents.

People can get it through exposure to the saliva, urine, or droppings of infected rodents. It typically does not spread from person to person; however, some health officials note that such transmission may be possible.

Through the test, only two hantavirus cases related to the ship have been confirmed. The others are also suspected by the WHO to be hantavirus and are being treated as an outbreak.

The source is still under investigation.

We take a closer look.

What happened on the ship

The Dutch company that operates the ship, the MV Hondius, offers “expedition cruises” that include trips to the Antarctic and several islands in the South Atlantic, allowing visitors to reach some of the remotest places on Earth.

The cruises can last a month or more and cost between $6,000 (Rs 572,000) and $25,000 (around Rs 23,85,000), depending on the cabin.

The MV Hondius set off from southern Argentina on April 1.

On April 6, the 70-year-old Dutch man fell ill with fever, headache and mild diarrhoea, WHO said.

Health workers get off the Dutch-flagged MV Hondius, a cruise ship carrying nearly 150 people, as it remains off Cape Verde on Monday, May 4, 2026, after three passengers died and several others fell seriously ill in a suspected hantavirus outbreak. AP

He died on board on April 11, after developing respiratory distress. The ship was between the British island territories of South Georgia and St. Helena in the middle of the South Atlantic, according to data from the ship tracking website MarineTraffic. The cause of death could not be determined, according to the cruise company, Oceanwide Expeditions.

The ship sailed on for nearly two weeks, stopping near the island of Tristan da Cunha before it reached St. Helena, where the Dutchman's body was taken off the ship on April 24. His 69-year-old wife disembarked with his body and flew to South Africa, while the man's body remained behind.

The woman, who already had symptoms, became sicker during the April 25 flight and collapsed at an airport in South Africa. She died at a hospital on April 26, the WHO said.

This undated photo provided by Oceanwide Expeditions shows the m/v Hondius, a Polar Class 6 passenger vessel, at sea. AP

Another passenger, a British man, became sick on the ship after it left St. Helena and sailed to tiny Ascension Island, some 1,300 kilometres (800 miles) north. He had a high fever, shortness of breath and signs of pneumonia, according to the WHO, and was evacuated from Ascension Island to South Africa on April 27. He is in an intensive care unit in a South African hospital.

The third fatality, a German woman, died on the ship on Saturday, again after it had set sail for a new destination — this time Cape Verde. She died four days after falling ill and also had signs of pneumonia, WHO said, which can be caused by hantavirus. Her body is still on the ship.

When authorities first knew hantavirus was on the ship

Health officials in South Africa ultimately tested the British man in intensive care for hantavirus after other extensive tests on him were negative. They received a positive result for hantavirus on Saturday, some 21 days after the first passenger died.

On Sunday, the WHO announced it was investigating a suspected hantavirus outbreak on the ship, which had by that time reached Cape Verde waters.

Research scientist Robert Nofchissey prepares samples of inactivated material as part of hantavirus research at the Centre for Global Health at the University of New Mexico Health Sciences Centre in Albuquerque, New Mexico, on Monday, May 4, 2026. AP

The British man's positive test prompted South African health authorities to also test the Dutch woman's body posthumously for hantavirus. That test came back positive on Monday.

WHO said the outbreak on the ship was being managed and the global risk was low, as hantavirus is not easily spread between people, though it added it was tracing people who were on a passenger plane between St Helena and Johannesburg, South Africa, with the Dutch woman.

What is the plan for the people still on board?

Oceanwide Expeditions said Tuesday that aircraft were flying to Cape Verde to evacuate two people needing urgent medical care and one passenger who was travelling with the German woman who died Saturday. They were to be taken to the Netherlands, but a timeline for arrival wasn’t clear.

The ship then would sail to Spain’s Canary Islands, a voyage of about three days, the company said.

Spanish officials had said they were monitoring and hadn’t confirmed any plans as of Tuesday evening.

Passengers and crew have been isolated in cabins with “maximal physical distancing,” WHO said, in a lockdown reminiscent of the Covid-19 pandemic.

The source of the infections

WHO says it is still investigating how a virus that is relatively rare in people got on board the ship. It said the Dutch man and his wife — whom it called cases one and two — had travelled in Argentina and elsewhere in South America before they boarded.

WHO reports that the Andes virus, a specific hantavirus species, is found in South America, primarily in Argentina and Chile.