Hantavirus outbreak on cruise ship MV Hondius involves Andes virus: WHO

Five of the eight cases reported from the cruise ship MV Hondius have been confirmed as hantavirus infections, and the virus involved is the Andes virus, World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus said on Thursday.

The outbreak aboard the cruise ship has infected eight people and resulted in three deaths. Tedros said during an online briefing that five symptomatic individuals have been laboratory-confirmed, while three others remain suspected cases.

None of the remaining passengers or crew on the ship is currently symptomatic, Tedros said, noting that the WHO is aware of reports of other people with symptoms who may have had contact with one of the passengers, and each case remains in close contact with the relevant authorities.

What do we know so far?

Two of the three death cases were close contacts and had travelled in South America, including Argentina, before boarding the cruise ship on April 1. The third fatality was an adult female who developed fever and a general feeling of being unwell on April 28, and was diagnosed with pneumonia before her death on May 2, according to information released by WHO.

Three patients, nationals of the Netherlands, Britain and Germany, were evacuated from the ship and transferred to medical facilities for treatment, according to the Dutch foreign ministry.

Switzerland also confirmed a case on Wednesday, a male patient who is currently being treated in isolation at a hospital in Zurich. His wife, who was with him throughout the voyage, has not developed any symptoms but has chosen to self-isolate as a precautionary measure.

In the United States, health authorities across at least three states are monitoring a number of individuals who may have been exposed to the infection. However, none of those under surveillance have displayed any symptoms to date, according to a report by the New York Times.

This cruise ship, with nearly 150 people on board, is expected to dock in Spain's Tenerife, in the Canary Islands, said Spain's health minister on Wednesday.

The strain in question

The Andes virus, a rare hantavirus found mainly in South America, is a rodent-borne virus capable of limited human-to-human transmission. Previous outbreaks showed transmission typically occurred through close and prolonged contact, particularly among household members and healthcare workers.

Unlike most hantavirus strains, the Andes can be transmitted to humans with limited capacity through close, prolonged contact and is primarily associated with Argentina and Chile, according to the WHO.

"Given the incubation period for the Andes virus, which can be up to six weeks, it's possible that more cases may be reported," Tedros said, adding that the WHO has assessed the overall public health risk as low.

What is hantavirus?

Hantaviruses are a family of viruses carried by rodents and occasionally transmitted to humans through contact with infected urine, droppings or saliva. Bites are a less common route of transmission. To date, human-to-human transmission has been documented only for the Andes virus.

The disease it causes depends largely on geography. In the Americas, infection can lead to Hantavirus Cardiopulmonary Syndrome – a rapidly progressing condition that attacks the lungs and heart. In Europe and Asia, it more commonly causes haemorrhagic fever with renal syndrome, which targets the kidneys and blood vessels. Both can be fatal.

There is no specific cure. Treatment relies on early supportive care and close monitoring of respiratory, cardiac and kidney function.

This outbreak also highlights the growing risk of transmission of climate-sensitive infectious diseases. Zhang Wenhong, a leading infectious disease expert and professor at Fudan University, told Yicai that this outbreak is "a textbook example of how climate change is redrawing the geographical boundaries of infectious disease." 

Beyond the visible ecological shifts that climate change brings, Zhang warned that it is also reshaping infectious disease risks in far subtler and more systemic ways. He noted that many of history's most serious disease outbreaks have stemmed from pathogens repeatedly attempting to breach the species barrier and enter human populations – a pattern, he stressed, that is deeply intertwined with human activity, environmental disruption and the pace of globalization.

How to reduce your risk

Infection is primarily prevented by limiting contact with rodents. Practical steps include keeping homes and workplaces clean, sealing entry points that rodents could use, dampening contaminated surfaces before cleaning to avoid inhaling particles, and maintaining good hand hygiene.

Authorities are continuing to monitor the situation as investigations into the source of the outbreak on board the MV Hondius remain ongoing.

(With input from Xinhua)

(Cover: WHO Director-General Tedros Adhanom Ghebreyesus speaks during a virtual press conference on the hantavirus cluster linked to cruise ship travel at WHO headquarters in Geneva, on May 7, 2026. /VCG)

For more:

Three dead in a suspected hantavirus outbreak on an Atlantic cruise ship

WHO shares update on cruise ship hantavirus cases

What we know about hantavirus