Argentina is investigating the source of a deadly hantavirus outbreak linked to a cruise ship, as cases in the country have doubled compared to last year. The health ministry reported 101 infections since June 2025, up from roughly half that number in the prior year. The Andes virus, a South American strain, causes hantavirus pulmonary syndrome, which has been fatal in nearly a third of recent cases.
The outbreak centres on the MV Hondius, a Dutch-flagged cruise ship that departed from Ushuaia, Argentina, for Antarctica. Three passengers have died, one is in intensive care in South Africa, and three others were evacuated on Wednesday. Another passenger who left the ship earlier tested positive in Switzerland. Argentina is sending genetic material and testing equipment to Spain, Senegal, South Africa, the Netherlands, and the UK to aid detection.
Authorities are tracing the movements of infected passengers before boarding. The virus incubates for one to eight weeks, making it unclear whether infection occurred in Argentina, during a stop at a remote South Atlantic island, or onboard. The WHO notes that human-to-human transmission is rare for hantavirus, but limited spread has been observed with the Andes strain.
Concern has arisen about 23 passengers who disembarked on Saint Helena on 23 April and returned to their home countries, including the United States. American passengers are being monitored in Georgia, California, and Arizona, with no symptoms reported so far. The WHO says the overall public health risk remains low.
