London School of Hygiene & Tropical Medicine

Three people have died after a suspected hantavirus outbreak on an Atlantic cruise ship that was travelling from Argentina to Cape Verde.

The World Health Organization (WHO) has reported two confirmed and five suspected cases aboard the MV Hondius ship. While human-to-human transmission of hantavirus is rare the WHO reportedly said that in this instance it could have been spread between "really close contacts".

Professor Roger Hewson of the London School of Hygiene & Tropical Medicine (LSHTM) said:

“Hantaviruses are a group of rodent-borne viruses that can cause severe disease in humans. They are found in different parts of the world, with different hantaviruses associated with different rodent hosts and different clinical syndromes. In the Americas, some hantaviruses can cause hantavirus pulmonary syndrome, a rare but potentially very severe illness affecting the lungs.

“The usual route of infection is exposure to infected rodents, particularly inhalation of virus from contaminated rodent urine, droppings or saliva. This is why investigations of suspected cases often focus on whether people may have had exposure to rodent-contaminated environments, food stores, cabins, storage areas or other enclosed spaces. Hantavirus is not generally considered easily transmissible between people.

“At this stage, based on the public information available, it’s important not to over interpret the cruise ship setting. The fact that cases have been identified in people associated with the same vessel does not by itself tell us whether exposure occurred on the ship, before boarding, during shore excursions, or through some other shared environmental exposure. That is precisely why public health investigations, laboratory confirmation and where possible, virus sequencing are important.

“Symptoms can initially be non-specific, including fever, muscle aches, headache and gastrointestinal symptoms, before some patients progress to respiratory illness. Diagnosis is usually made through specialist laboratory testing, including serology to detect recent infection and molecular tests where appropriate.

“The key public health message is that hantavirus infections are uncommon and the wider public risk is generally low. The priority is careful clinical management of affected individuals, laboratory confirmation, investigation of potential rodent exposure and proportionate public health follow-up of close contacts and shared environments.”

This is a rapid reaction to a breaking news story. It was updated on 5 May 2026 to reflect that there are two confirmed cases and WHO comments that it could have spread between close contacts.