Deadly Virus Outbreak on Polar Expedition Ship

By Alexander Fernandez

Reporter, Life News Today

What began as a polar voyage from the southern tip of South America shifted into an international public health investigation after authorities confirmed hantavirus infections linked to the MV Hondius, a Dutch-flagged expedition ship that navigated the remote South Atlantic. Dr. Maria Van Kerkhove, acting director for epidemic and pandemic preparedness and prevention at the World Health Organization (WHO), said seven of the 147 passengers and crew had fallen ill, three of them fatally. WHO’s outbreak report said the cluster included two laboratory-confirmed cases, five suspected cases and three deaths. The Netherlands’ National Institute for Public Health and the Environment (RIVM) later identified the virus as the Andes variant, a detail that widened the scope of inquiry. Authorities had not publicly linked every illness or death among the group to hantavirus, leaving the full extent of the outbreak unresolved.

The Hondius left Ushuaia, Argentina, on April 1 with 88 passengers and 59 crew members from 23 countries. The ship traveled through Antarctica, South Georgia, Nightingale Island, Tristan da Cunha, St. Helena and Ascension Island, crossing remote ocean areas far from major ports and hospitals. WHO said illness onset occurred between April 6 and April 28, and investigators still had not determined how much contact passengers had with local wildlife during the trip or before boarding in Ushuaia. By early May, the ship’s original plans had given way to a multinational response involving WHO, the European Centre for Disease Prevention and Control, Cabo Verdean health authorities, South Africa’s National Institute for Communicable Diseases and officials from the Netherlands, Spain, the United Kingdom and Argentina. Officials asked passengers to stay in their cabins while the crew carried out medical checks, cleaning and containment measures. Medical staff from Cabo Verde joined the effort to care for the sick, protect others on board and determine where the virus entered the journey.

WHO received the first international alert May 2, when officials reported severe respiratory illnesses aboard the Dutch ship, including two deaths and one patient in critical condition. South Africa’s National Institute for Communicable Diseases (NICD) confirmed hantavirus in two patients, with further testing underway. Van Kerkhove said hantaviruses are carried by some rodents and “can cause severe illness in humans and they can be fatal.” People usually become infected through contact with infected rodents or their urine, droppings or saliva, she said.

Dutch public health officials confirmed the virus as the Andes variant of hantavirus, a strain most often found in the Americas and known for causing high fever, respiratory distress and severe complications. RIVM said in a May 6 update that “the virus on board the cruise ship Hondius is the Andes variant of the hantavirus,” a finding confirmed by laboratory testing. The identification forced investigators to retrace the ship’s journey, a path that crossed open ocean, remote islands and multiple borders, searching for the moment when a rodent-borne virus slipped aboard.

The Andes variant shifted the investigation from a search for a single environmental exposure to a broader review of where passengers went, who shared cabins and whether close contact aboard the ship played any role. Most hantaviruses spread through infected rodents or their waste, but the Andes variant has been linked in rare cases to person-to-person transmission, usually after close contact. Investigators worked to determine whether the cluster began before boarding, during landings on remote islands or through contact among passengers after the voyage began.

Investigators then worked backward from the timing of the illnesses. Based on the incubation period, WHO suspected the first infections may have occurred before passengers boarded, possibly during activities connected to wildlife. Some islands along the route had rodents, leaving open the possibility of exposure during landings, while officials also reviewed close contact among passengers and cabinmates. “We’re looking at a full exposure history of everybody who is on board, where they were, what they were doing, if they came into contact with wild animals,” Van Kerkhove said.

The cases soon spread across health systems rather than remaining a single shipboard emergency. The Netherlands’ Ministry of Foreign Affairs reported two Dutch deaths, one confirmed as hantavirus, while another passenger hospitalized in Johannesburg also tested positive. A passenger who died May 2 remained under review, leaving investigators to separate confirmed infections from illnesses and deaths still awaiting final classification.

Oceanwide Expeditions, the ship’s operator, said conditions on the Hondius remained calm while it anchored off Cabo Verde. “The atmosphere on board m/v Hondius remains calm, with passengers generally composed,” the company said in a May 4 update. The company said it kept guests informed, supported them and followed strict health and safety procedures, including isolation, hygiene measures and medical checks.

Passengers on the ship described the waiting period as uncertain and cautious, relying on daily routines while larger decisions remained out of their control. Jake Rosmarin, a passenger, said in a May 4 Instagram video that “there’s a lot of uncertainty, and that’s the hardest part.” Rosmarin added, “All we want right now is to feel safe, to have clarity and to get home.” Another passenger, Qasem Elhato, 31, said in comments sent via WhatsApp and published May 5 that daily life on the ship stayed steady as everyone waited for updates. “Our days have been close to normal, just waiting for authorities to find a solution,” Elhato said. “But morale on the ship is high and we’re keeping ourselves busy with reading, watching movies, having hot drinks and that kind of things.”

As the Hondius remained anchored off Cabo Verde, the response shifted from diagnosis to evacuation. On May 6, medical teams removed three people, including the ship’s doctor, from the vessel, transported them by ambulance to Nelson Mandela International Airport and flew them out under the care of specialized teams. Cabo Verdean authorities, citing public health concerns, barred the ship from docking but dispatched medical teams to assist with evacuation and provide psychological support to those still aboard.

Spain later agreed to let the ship dock in the Canary Islands after WHO asked for help under the International Health Regulations (IHR). Spain’s health minister, Mónica García, said after a meeting led by Prime Minister Pedro Sánchez that the ship would go to the port of Granadilla de Abona in Tenerife once all sick passengers had been evacuated. García said the help and repatriation process would happen in the Canary Islands and “will not pose any risk to the Canarian population or to its economic activity,” according to La Moncloa, Spain’s official government website.

García said officials evacuated the three people with symptoms from Cabo Verde to the Netherlands and that “all those who remain on the ship are asymptomatic passengers” as of May 6, according to La Moncloa. She explained that officials would check the 14 Spanish passengers when they arrived in the Canary Islands, fly them by military plane to Torrejón Air Base and take them to Gómez Ulla military hospital in Madrid, where they would stay in quarantine as long as needed.

The United Kingdom also started making plans for British nationals to return from the ship. The UK Health Security Agency (UKHSA) said officials had evacuated three people, including one British national, from the Hondius to receive medical care in the Netherlands. Other British nationals could return home after the ship docked, as long as they did not show symptoms. Dr. Meera Chand, deputy director for epidemic and emerging infections at UKHSA, said, “Our thoughts are with all those affected by the hantavirus outbreak onboard the MV Hondius.”

Chand said the risk to the general public remained very low, but UKHSA prepared to “support, isolate and monitor British nationals from the ship on their return to the UK” and trace anyone who might have had contact with the ship or related cases. UKHSA also said two people who returned to the United Kingdom on their own after being on the Hondius had no symptoms and were told to self-isolate.

By May 6, the Swiss Federal Office of Public Health (FOPH) confirmed that a passenger from the voyage’s first leg, Ushuaia to St. Helena, had tested positive and was receiving treatment in Zurich. His wife, who had no symptoms, entered self-isolation. The case expanded the map of the outbreak beyond the vessel itself, showing how a voyage through remote waters had become a public health inquiry reaching hospitals and agencies across several countries.

The outbreak left health authorities with a problem that stretched beyond the ship: how to care for the sick while reconstructing a journey that moved through remote islands, international waters and multiple health systems before the virus was confirmed. For the Hondius, a trip that began as an expedition through the South Atlantic now ends under medical scrutiny, with investigators still working to determine how a rodent-borne virus reached a ship so far from land.