90-Second Read: Are cruise ships really breeding grounds for illness?

A viral Hantavirus outbreak on the Oceanwide Expeditions' MV Hondius cruise ship was already commanding worldwide attention last week when health officials reported another: a norovirus outbreak on the Princess Cruises' Caribbean Princess. These incidents have many travelers asking if cruises are breeding grounds for illnesses and germs? Norovirus outbreaks on cruises, for example, account for just 1% of all reported cases, according to the CDC. The latter marked the fourth outbreak of gastrointestinal illness on cruises to meet the Centers for Disease Control and Prevention's threshold for public notification in 2026.

The MV Hondius outbreak, which prompted a coordinated response from the World Health Organization and other international authorities, evoked aspects of the early days of the COVID-19 pandemic. In 2020, cruise ships became early sites of high-profile outbreaks, including aboard Princess Cruises' Diamond Princess. One of the things about surviving a health crisis is moving quickly, so cruise lines should learn from this that clarity, sympathy and corrective action are central to building that trust. These events shouldn't necessarily dissuade passengers from setting sail, health experts add.

Ian Lipkin, John Snow Professor of Epidemiology and Director of the Center for Infection and Immunity at Columbia University's Mailman School of Public Health. The closer the proximity, the more likely travelers could spread illness to one another via respiratory droplets or surfaces. Hantavirus is primarily spread through exposure to the urine, droppings or saliva of infected rodents. WHO official Maria Van Kerkhove previously said the organization believes the first guest to show symptoms and his wife, both of whom died, were infected on land, but that there may have also been some human-to-human transmission among "really" close contacts.

And while officials said the confirmed cases from MV Hondius were the Andes virus, which can be transmitted from person to person, they are still working to determine the origin. Lipkin added that "this Andes virus outbreak is really an outlier," however. Infectious diseases spread in plenty of other settings, too.