Hantavirus aboard MV Hondius: novel pathogens in confined maritime environments and the limits of post-COVID-19 preparedness

The World Health Organization (WHO) has confirmed an unprecedented Hantavirus outbreak on the MV Hondius, a Dutch-flagged polar expedition cruise ship operated by Oceanwide Expeditions, which left Ushuaia, Argentina, on April 1, 2026, en route to Cape Verde via Antarctica, the Falkland Islands, and Saint Helena 1 .By early May 2026, multiple laboratory-confirmed cases had been identified among passengers and crew from 23 nationalities, including three fatalities and several critically ill patients requiring international medical evacuation 2,3 .Exposed passengers subsequently dispersed across Europe, North America, Africa, and Asia, triggering a complex multinational public health response.To our knowledge, this represents the first documented hantavirus outbreak associated with a passenger cruise vessel.Passengers boarded the Hondius in Ushuaia, Argentina, an Andes virus-endemic region.Hantavirus occurs in Patagonia and Northern Argentina.Ushuaia, an island at the southernmost part of the country, has not been noted as a common location for hantavirus.The index case had travelled for 125 days with his wife in Argentina, Chile and Uruguay before the cruise, and may have acquired infection in the two months before boarding, most likely in Argentina, where they had spent the most time during the longest potential incubation period of two months.The outbreak is notable not only because of the rarity and severity of hantavirus infection, butVaman RS, Quigley AL, Bari N, Chughtai AA, MacIntyre CR .Hantavirus aboard MV Hondius: novel pathogens in confined maritime environments and the limits of post-COVID-19 preparedness.Global Biosecurity.2026; 8(1).