90-Second Read: With fears of Hantavirus outbreak, here's the real pandemic risk

A deadly respiratory viral outbreak aboard a cruise ship in the Atlantic Ocean has spurred fears about another pandemic. The World Health Organization and the Centers for Disease Control and Prevention both say the Hantavirus outbreak aboard the MV Hondius — which has infected eight people and left three dead — has low risk to public health. In 2026, the United States formally exited WHO, which caught this Hantavirus outbreak through its early warning system. Hantavirus, the name for viruses derived from rodents that can infect humans, aren't typically transmissible from person to person. Still, the current outbreak is a warning sign of what's to come with zoonotic diseases that move from animals to people, public health experts say.

Notably, a COVID-19 outbreak aboard the Diamond Princess cruise ship affected hundreds in early 2020 as the coronavirus pandemic began. The Hondius ship stopped at several remote locations before WHO was notified of the cluster of cases with severe acute respiratory illness among passengers and crew, so officials are working to track cases. Then, the outbreak resulted in 34 confirmed cases and 11 people dead. The passengers have been on the ship since April 1, and they're set to disembark May 11, which would be at the end of when symptoms can occur between 1 and 6 weeks. Peter Hotez, dean of Baylor College of Medicine's National School of Tropical Medicine, said there may be some new cases arising as people get set to head to their home countries.

However, the Andes virus type aboard the Hondius is known to spread between people, albeit rarely, and most often from prolonged, close contact with a symptomatic person who has the respiratory disease, according to the CDC. However, it's unlikely to cause a wider epidemic, let alone a pandemic, given how the virus has spread. Like other cruise ships that require people to be in close quarters, Hotez said, those conditions can easily spread disease. This includes known viruses such as Hantavirus, but also unknown pathogens circulating in nature. On April 1, the couple boarded the cruise ship departing from Ushuaia, Argentina, with nearly 150 others.

A 2020 New England Journal of Medicine article identified person-to-person transmission of Andes virus during a deadly outbreak in Patagonian Argentina, in Chubut Province, further north from where the Hondius departed. The more that we allow these new interfaces to open up, the more we're just rolling the dice. In the South Atlantic, temperatures currently are cooler, forcing people indoors instead of, say, a Caribbean carnival ship where people aren't as in close contact while enjoying warm weather outside. Researchers found attending mass gatherings or having extensive contact with others contributed to increased likelihood of transmission. Researchers found a higher presence of viral antibodies coupled with attending mass gatherings and having extensive contact with others.