WHO says hantavirus outbreak on cruise ship not expected to trigger large epidemic

The World Health Organization (WHO) said on Thursday that a hantavirus outbreak linked to a cruise ship is not expected to develop into a large epidemic, stressing that the situation is different from the COVID-19 pandemic.

“It’s a specific, confined setting where people are interacting in prolonged close contact,” Abdirahman Mahamud, WHO’s director for health emergency alert and response operations, told reporters in Geneva.

"We don't anticipate a large epidemic with the experience our member states have and the actions they have taken," he said. “We believe that this will not lead to subsequent chains of transmission."

WHO officials told the press briefing that five cases have so far been confirmed involving the Andes virus, a hantavirus strain that can spread between humans in rare cases involving close and prolonged contact.

Mahamud said confirmed cases should remain isolated, while exposed individuals should undergo active monitoring for up to 42 days, though implementation may vary by country.

He said some countries may use institutional quarantine while others may rely on daily health monitoring by healthcare workers.

Maria Van Kerkhove, WHO’s director for epidemic and pandemic preparedness and prevention, stressed that the situation differs significantly from the COVID-19 pandemic.

“This is not SARS-CoV-2. This is not the start of a COVID pandemic,” she said.

“It doesn’t spread the same way like coronaviruses do,” she added, noting that most hantaviruses are transmitted through rodents, their saliva, urine or droppings, while human-to-human transmission is uncommon.

WHO Director-General Tedros Adhanom Ghebreyesus, for his part, said the agency has informed 12 countries whose nationals had previously disembarked in Saint Helena: Canada, Denmark, Germany, the Netherlands, New Zealand, Saint Kitts and Nevis, Singapore, Sweden, Switzerland, Türkiye, the UK and the US.

Tedros said the first two confirmed cases had traveled through Argentina, Chile and Uruguay before boarding the ship, including visits to bird-watching sites where rats known to carry the Andes virus were present.

The ship is currently sailing toward the Canary Islands, with WHO saying both the overall public health risk and the risk to the islands remain low.