Three people have died and several others have fallen ill in a hantavirus outbreak linked to the MV Hondius, a luxury cruise ship currently anchored near Cape Verde. Health officials are monitoring the situation as the vessel, which departed from South America in early April, continues its journey toward Spain’s Canary Islands.

As of Wednesday, eight cases have been identified or suspected among the nearly 150 passengers and crew on board, with five confirmed through laboratory testing. Three individuals—two confirmed hantavirus patients and one suspected case—were evacuated from the ship and flown to the Netherlands for advanced medical care. The evacuated group includes a 41-year-old Dutch national, a 56-year-old British national, and a 65-year-old German national. Two remain in serious condition, according to the ship’s operator Oceanwide Expeditions, while the third shows no symptoms but had close contact with a passenger who died onboard last Saturday.

The outbreak appears linked to the Andes hantavirus strain, a species primarily found in Argentina and Chile. Authorities believe the virus likely originated from exposure to rodents or their droppings, which typically transmit hantaviruses. Uniquely, the Andes virus can spread between humans, though this is considered rare and generally requires close, sustained contact. Symptoms typically emerge one to eight weeks after exposure and include fever, muscle pain, and gastrointestinal issues. The strain often leads to hantavirus cardiopulmonary syndrome, a severe respiratory illness with a fatality rate of up to 50 percent. There is no specific antiviral treatment; care is primarily supportive, involving oxygen therapy or mechanical ventilation when necessary.

Investigators from South America, including Argentine officials, are probing the outbreak’s origins. Initial hypotheses suggest a Dutch couple contracted the virus while bird-watching near Ushuaia, Argentina, particularly in a landfill site known for rodent activity. This region had not previously reported hantavirus cases. The couple boarded the MV Hondius, potentially introducing the infection to the ship. Subsequent cases and fatalities have been reported in multiple countries, including South Africa and Switzerland, as passengers disembarked or traveled onward. Swiss authorities confirmed treatment of a former passenger in a Zurich hospital, while South African officials traced contacts of infected individuals, with most testing negative to date.

Those remaining on the MV Hondius are reportedly asymptomatic and isolating in their cabins while the ship completes its approximately three- to four-day passage to the Canary Islands. Spanish health authorities stated the ship’s arrival poses no public health risk. However, regional officials in the Canary Islands have expressed concern and sought government consultations.

The World Health Organization (WHO) has emphasized that the outbreak does not represent a high public health risk akin to respiratory viruses such as COVID-19. According to WHO’s epidemic expert Maria Van Kerkhove, this outbreak is unusual because it is the first documented hantavirus cluster on a cruise ship, but the overall risk to the general population remains low. Dutch infectious disease specialists have joined efforts on board to provide clinical support and assist with containment measures. Meanwhile, contact tracing continues internationally, as health authorities seek to identify potential exposures among passengers, crew, and others who may have interacted with them during or after the voyage.