The World Health Organisation has revealed that the first confirmed hantavirus infection linked to the deadly outbreak aboard the MV Hondius cruise ship likely occurred before the passenger boarded the vessel.
The expedition ship departed Ushuaia, Argentina, on April 1 for a trip across the Atlantic Ocean to Cape Verde, carrying around 150 passengers and crew members.
According to the WHO, the first victim, a 70-year-old Dutch passenger, started experiencing symptoms such as fever, headache and mild diarrhoea on April 6 before his condition worsened into respiratory distress. He later died on board on April 11.
Anais Legand, a WHO specialist on viral haemorrhagic fevers, said investigations showed the infection did not originate on the ship or during visits to islands along the route.
“The incubation period — the time between infection and the onset of symptoms — is between one and six weeks but it is typically more like two to three weeks,” she said.
“The man very clearly had exposure before boarding the ship. For this virus, there is no evidence that the disease can be transmitted to someone before symptoms appear.”
Legand added that the source of exposure was “certainly linked to a rodent”.
Health experts say hantavirus is commonly spread through contact with infected rodents or exposure to their saliva, urine or droppings.
Authorities noted that human-to-human transmission has only been confirmed with the Andes strain of the virus, which was identified in the outbreak cases.
The WHO disclosed that the Dutch couple involved in the outbreak had travelled through parts of South America, including Argentina, before joining the cruise.
Investigators in Argentina suspect the pair may have contracted the virus while bird-watching near a landfill site in Ushuaia, where rodents were likely present.
So far, three people — the Dutch couple and a German passenger — have died in connection with the outbreak.
WHO Director-General Tedros Ghebreyesus said on X that eight cases had been identified as of May 6, with three laboratory-confirmed as hantavirus infections.
Swiss health authorities also confirmed another hantavirus case involving a passenger from the cruise ship who later sought treatment at a hospital in Zurich.
Meanwhile, two confirmed patients and one suspected case were evacuated from the vessel on Wednesday before the ship left Cape Verde and continued its journey toward Spain’s Canary Islands.
