A British crew member required urgent medical treatment and a UK passenger remained critically ill but stable after a suspected hantavirus cluster aboard the expedition ship MV Hondius in the Atlantic. The vessel, which left southern Argentina in March with 149 people from 23 countries, has been anchored off Cape Verde after several people became unwell and passengers and crew were isolated on board while the World Health Organization investigates.
As of 4 May 2026 the WHO reported seven cases associated with the ship: two laboratory-confirmed hantavirus infections and five suspected cases. Those seven include three deaths, one patient in critical condition and three people with mild symptoms. The UN agency linked the fatalities to a married Dutch couple and a German national. A hantavirus variant was identified in the British patient who was evacuated to an intensive care unit in Johannesburg, South Africa.
Oceanwide Expeditions, the ship operator, said two staff members—a British and a Dutch crew member—were showing acute respiratory symptoms. One crew member’s symptoms were described as mild and the other severe; both required urgent medical attention, though hantavirus has not been confirmed in the crew members. The company said the first passenger died on 11 April and was disembarked at St Helena on 24 April with his wife; she later fell ill and died after collapsing at a South African airport while trying to return to the Netherlands. A German passenger died on 2 May.
Cape Verdean authorities have denied the Hondius permission to dock near Praia, Santiago island, citing the need to protect national public health. Local officials said they were coordinating with Dutch and UK authorities on clinical monitoring and possible air-ambulance evacuations. Oceanwide said it was exploring a move to Spain’s Canary Islands—Las Palmas or Tenerife—for further medical screening and care, and was working with Dutch authorities on repatriation plans that would cover the return of a deceased passenger and a closely associated guest.
The Dutch National Institute for Public Health (RIVM) is assisting the investigation but said the source of infection remains unclear. Investigators are considering several possibilities, including exposure to infected rodents aboard the vessel or during a stop in South America. South Africa’s National Institute for Communicable Diseases has carried out contact tracing in Johannesburg around the evacuated patient to identify potential exposures.
The WHO stressed that the risk to the general public is low and said there is no basis for panic or travel restrictions. The UK Foreign, Commonwealth & Development Office said it was closely monitoring the situation and in contact with the cruise operator and local authorities.
Hantaviruses are typically transmitted to people through contact with infected rodents’ urine, droppings or saliva and can cause severe respiratory illness and death. Human-to-human transmission is uncommon but has been documented in a limited number of outbreaks. Authorities point to a 2019 cluster in southern Argentina that killed at least nine people as a reminder of the virus’s potential severity.
Passengers on the Hondius reported uncertainty and distress about next steps and called for clearer information and repatriation arrangements. Oceanwide said strict onboard precautions remained in place, including isolation of suspected cases, reinforced hygiene measures and ongoing medical monitoring.