Why the Hantavirus cruise ship outbreak is unlikely to become a global crisis

Cruises are like that Closely related to the disease, the highly contagious norovirus is called the “cruise ship virus.”

But a ship bound for Spain’s Canary Islands has attracted global attention due to a rare outbreak of Hantavirus that has left three people dead. Despite the concern, health officials and infectious disease experts say the risk to the general public right now is low because Hantavirus is less contagious than other respiratory illnesses like the coronavirus responsible for the COVID-19 pandemic.

“This is not Covid, this is not influenza. It spreads very differently,” Maria Van Kerkhove, director of pandemic preparedness and prevention at the World Health Organization, said at a news conference on Thursday.

During the press conference, WHO Director-General Tedros Adhanom Ghebreyesus confirmed eight cases of Hantavirus infection among passengers on the MV. Hondius Luxury cruise ship, including the three who died. Hantavirus is usually transmitted by rodents and can cause severe illness in humans. People usually contract the disease by breathing air contaminated with the droppings, urine, or saliva of infected rodents. But the specific strain identified in the cruise ship cases, called Andes virus, can spread between people.

Health officials in several countries are working to trace the contacts of 29 people who disembarked from the ship on the remote South Atlantic island of St. Helena on April 24, about two weeks after the first death from the Hanta virus occurred. A Swiss man who left the ship early has tested positive for the virus and is undergoing treatment, and two people in the UK are said to be self-isolating after returning home. Six people from the United States were among those who disembarked the ship.

“The administration is closely monitoring the situation with U.S. passengers on the M/V Hondius cruise ship who tested positive for Hantavirus,” the Centers for Disease Control and Prevention said in a statement on Wednesday.

However, experts say there is no need to panic at this stage.

“It doesn’t spread very well, so I don’t have any concerns that this will be the next Covid virus,” says Stephen Bradfoot, an immunologist and associate director of the Center for Global Health at the University of New Mexico. “Most cases of the spread of this virus in the past have been through close contacts — people sharing a bed, people sharing food, that kind of thing.”

The virus does not spread easily by casual contact, and asymptomatic spread — a major driver of Covid cases during the pandemic — is also less likely. Available data on the Andean virus suggests it is more likely to be transmitted when someone is visibly ill, Bradfoot says. Symptoms include fever, muscle aches, fatigue and dizziness, which can progress to coughing, shortness of breath and difficulty breathing.

“This is really useful, because it makes it a lot easier to do contact tracing and identify high-risk individuals,” he says, though he cautions that Andean virus outbreaks are uncommon, and just because the virus has behaved one way in the past doesn’t mean it always will. “Infections have been rare enough that we can’t say that with certainty.”

One such outbreak occurred from late 2018 to early 2019 in the Patagonia region of Argentina, caused by a birthday party attended by about 100 people. Three people were the main drivers of the outbreak, which led to 34 cases and 11 deaths. Study authors who tracked the outbreak in detail found that 26 of the 34 cases contracted the disease after close contact with an infected person, including people who did not attend the party. Six people were likely exposed to the virus via droplets or aerosols.