National Geographic Experts explain why the outbreak aboard a Dutch cruise ship is so rare—and how much of a risk it poses. It’s not extraordinary for a cruise ship to be afflicted by an eruption of infectious diseases. But the recent cluster of hantavirus cases on the M.V. Hondius, a Dutch polar expedition vessel sailing from Argentina to the Canary Islands, was “definitely a surprise,” says Steven Bradfute, an immunologist and hantavirus researcher at the University of New Mexico Health Sciences Center.
Gastrointestinal infections like norovirus and E. coliare most common, although respiratory infections also sometimes cause onboard outbreaks, as when COVID-19 stranded the Grand Princess off the shores of California in the early days of the pandemic.
However, this is the first cruise ship-associated outbreak of hantavirus Bradfute says he has heard of, and its circumstances are concerning enough that public health officials are watching closely. On May 6, the World Health Organization announced that the virus involved in the cluster was an Andes virus.
So far, eight cases have been identified, including three deaths, one person who is critically ill, three who have mild symptoms, and a newly identified patient in Switzerland who had traveled on the ship. All but the newly identified patient developed symptoms between April 6 and 28 and experienced fever and gastrointestinal symptoms, with rapid progression to pneumonia, leading to cardiovascular collapse for some.
The ship remains stranded after it was refused permission to dock in Cape Verde, and its remaining passengers are confined to their cabins.
What is hantavirus and how does it spread among humans? Here’s everything you need to know.