WHO says hantavirus outbreak poses low public health risk

The World Health Organization said a hantavirus outbreak aboard the Dutch-flagged MV Hondius remains a low risk to public health and is "not the start of a pandemic" despite eight reported cases, consisting of five confirmed and three suspected, along with three deaths.

WHO Director-General Tedros Adhanom Ghebreyesus said the outbreak involves the Andes virus, a strain of hantavirus that can, in rare cases, spread between humans through close and prolonged contact.

"While this is a serious incident, WHO assesses the public health risk as low," Tedros said in Geneva, adding that the organization is working with multiple governments and health agencies to prevent further spread of the virus and ensure treatment for affected passengers.

WHO stressed that the outbreak does not resemble the early stages of the COVID-19 pandemic because hantaviruses spread very differently and are primarily transmitted through infected rodents rather than sustained human-to-human transmission.

Maria Van Kerkhove, WHO's chief of epidemic and pandemic preparedness and prevention, said the situation is fundamentally different from COVID-19.

"This is not the start of a pandemic. This is not COVID," she said. "It doesn't spread the same way coronavirus does. It's very different."

WHO said most hantaviruses are primarily transmitted from infected rodents to humans, with human-to-human transmission being rare.

The organization said none of the remaining passengers or crew aboard the vessel are currently showing symptoms, though monitoring continues due to an incubation period of up to six weeks. A flight attendant who had been under medical observation after possible exposure to an infected passenger later tested negative.

Medical experts from WHO, the Netherlands and the European Centre for Disease Prevention and Control are conducting ongoing assessments aboard the ship, while isolation and disinfection measures remain in place, said Tedros.

WHO said investigations traced the outbreak to a passenger who developed symptoms on April 6 and died on board on April 11. Because the illness initially resembled other respiratory infections, hantavirus was not suspected at the time.

His wife also became ill and disembarked at St. Helena, a remote island in the South Atlantic, before deteriorating during a flight to Johannesburg on April 25 and dying the following day.

Subsequent laboratory testing by South Africa's National Institute for Communicable Diseases confirmed hantavirus infection, linking the deaths to the cruise ship outbreak.

WHO said eight cases have now been reported, including five confirmed and three suspected infections, with several patients evacuated for treatment, including transfers to hospitals in the Netherlands, Germany and South Africa, where one remains in intensive care.

The organization said it had notified 12 countries after passengers disembarked at St. Helena, as international monitoring continues.

The UK Health Security Agency confirmed two British nationals had tested positive, with another suspected case from Tristan da Cunha, and said all British passengers and crew returning from the vessel will be required to isolate for 45 days.

Several countries, including France, Denmark and Canada, reported isolated or asymptomatic cases linked to the voyage, with passengers either under testing or precautionary monitoring.

South African authorities continue contact tracing linked to an April 25 flight from St. Helena to Johannesburg.

The US Centers for Disease Control and Prevention classified the outbreak as a Level 3 emergency, the lowest level of activation.

The MV Hondius is expected to arrive in Tenerife, Spain's Canary Islands, on Saturday or Sunday, where authorities are preparing isolated evacuation procedures for passengers and crew. The United States has arranged a repatriation flight for 17 citizens, while Britain plans to charter a flight for nearly two dozen nationals.

Agencies contributed to this story.