Hantavirus Cluster on Antarctic Cruise Ship Grows to Five Confirmed Cases as Medical Evacuations Begin

Confirmed cases of hantavirus linked to the cruise ship MV Hondius have risen to five, with three deaths recorded since April and medical evacuations now underway from the vessel, which remains at sea with 147 passengers and crew from 23 countries.

The Details

The World Health Organization confirmed on May 6 that two additional patients aboard the Dutch-flagged expedition vessel MV Hondius have tested positive for hantavirus, bringing the total confirmed cases to five. Both newly confirmed patients were medically evacuated from the ship on May 6 and are reported to be in serious condition. A third individual, an asymptomatic close contact of a German national who died on May 2, was also evacuated.

The three previously confirmed cases include a woman who had already disembarked and was traveling home to the Netherlands, a British national currently in critical but stable condition in a Johannesburg hospital, and a passenger receiving treatment at University Hospital Zurich who self-presented after receiving an email from the ship's operator.

Three deaths have been documented in the outbreak. An adult male, designated Case 1, died on board on April 11. His body was removed to Saint Helena on April 24. An adult female close contact of Case 1 died in a Johannesburg emergency department on April 26. A fourth case, an adult female, died on board on May 2. A German national who was a close contact of one of the individuals evacuated on May 6 also died on May 2.

South Africa's National Institute for Communicable Diseases and Geneva University Hospitals have identified the virus as Andes hantavirus. This strain has historically demonstrated potential for limited person-to-person transmission, though hantavirus cardiopulmonary syndrome is primarily acquired through contact with the urine, feces, or saliva of infected rodents.

The vessel, operated by Netherlands-based Oceanwide Expeditions, carries 88 passengers and 59 crew. It departed Ushuaia, Argentina on April 1 for an Antarctic expedition cruise with stops including mainland Antarctica, South Georgia, Nightingale Island, Tristan da Cunha, Saint Helena, and Ascension Island.

Context

Hantavirus infections carry a case fatality rate of up to 50% in the Americas, according to WHO data. There are no specific vaccines or approved antiviral treatments for hantavirus cardiopulmonary syndrome; treatment relies on early supportive care and intensive care unit management.

The ship's itinerary through remote, ecologically diverse regions in the South Atlantic and Antarctic raises questions about the route of exposure, though the exact source—whether during shore excursions or onboard—has not been definitively established in public reporting.

WHO Director-General Dr. Tedros Adhanom Ghebreyesus stated on May 6 that the organization continues to monitor the health of passengers and crew. In a post on X, Dr. Tedros said, "WHO continues to work with the ship's operators to closely monitor the health of passengers and crew, working with countries to support appropriate medical follow-up and evacuation where needed." He added, "Monitoring and follow-up for passengers on board and for those who have already disembarked has been initiated in collaboration with the ship's operators and national health authorities." Dr. Tedros assessed that "the overall public health risk remains low."

Passengers and crew have been advised to practice maximal physical distancing, remain in cabins where possible, and monitor symptoms for 45 days. Oceanwide Expeditions announced it is expanding medical care on board, with two infectious disease physicians arriving by plane from the Netherlands in partnership with the RIVM, the Dutch Institute for Public Health and Environment.

The ship is expected to sail to Tenerife in the Canary Islands, but regional president Fernando Clavijo has publicly opposed allowing it to dock, citing what he described as a lack of information and insufficient safety guarantees. Clavijo told radio station COPE: "This decision is not based on any technical criteria, nor is there sufficient information to reassure the public or guarantee their safety." In contrast, Spain's health minister Monica Garcia said a joint screening and evacuation mechanism will launch upon arrival at Granadilla de Abona port, with repatriation to proceed through the European civil protection mechanism.

What's Next

The immediate focus remains on the medical evacuation and monitoring of the vessel's remaining passengers and crew. The two infectious disease specialists from the Netherlands are expected to arrive aboard to bolster onboard medical capacity. Spanish authorities are preparing screening and evacuation infrastructure at Granadilla de Abona, though political opposition from Canary Islands leadership leaves some uncertainty about whether the ship will be permitted to dock at Tenerife as planned. WHO has not issued a new Disease Outbreak News since May 4, when it reported seven total cases—two laboratory-confirmed and five suspected—meaning the status of the remaining suspected cases remains unclear. The organization continues to coordinate with national health authorities on follow-up for passengers who have already disembarked across multiple countries.