The Centers for Disease Control and Prevention (CDC) published a report in October 2024 stating there were at least twelve Legionnaires’ disease occurrences on two cruise ships. Ten cases were serious enough that cruise passengers required hospitalization. The CDC did not identify the cruise line(s) involved.
This story was first reported by Travel + Leisure.
The CDC concluded, based on “epidemiologic, environmental, and laboratory evidence” that private hot tubs are subject to “less stringent operating requirements than are public hot tubs, and operating protocols were insufficient to prevent Legionella growth.”

Travel + Leisure magazine explained the CDC’s findings in its article: “Hot tubs can be a source of Legionella growth and transmission when they are inadequately maintained and operated. It is important for cruise ship operators to inventory hot tub–style devices across their fleets, evaluate the design features that increase the risk for Legionella growth and transmission, and test for Legionella,” a CDC spokesperson told Travel + Leisure.
The CDC included the information below in its report:
- Private hot tubs found to be the source of disease outbreak by the CDC.
- Twelve cases of Legionnaires’ disease over course of twenty months in hot tubs on cruise guests’ private balconies.
- Poor cleaning standards on private hot tubs led to rapid bacteria growth.
The New York Post dramatically writes, “Cruise ship passengers splash out big bucks for private hot tubs in their own staterooms all the time — but the Center for Disease Control is warning against the exclusive amenity, calling them a bubbling breeding ground for Legionnaires’ disease.”
The New York Post also chimed in an article titled Don’t splash out for this coveted cruise ship extra — it’s a breeding ground for disease, experts warn on another disease that cruise passengers are increasingly facing, fast-spreading norovirus: “Meanwhile, Legionnaires isn’t the only unwelcome guest on deck. Norovirus — a notorious cruise ship nemesis — is also making waves . . .”
Norovirus outbreaks on cruise lines are pacing at record levels with 16 gastrointestinal (GI) outbreaks already in 2025 compared to just 18 total in 2024. The CDC reported the spike is likely due to a new norovirus strain.
This all comes as the CDC’s Vessel Sanitation Program (VSP), which inspects cruise ships and responds to GI outbreaks, recently experienced staffing cuts at the Department of Health and Human Services under the Trump administration. Read more: New Norovirus Strain, Public Health Program “Mistakenly” Cut, and Sixteen Gastrointestinal Outbreaks on Cruise Ships in First Four Months of 2025
Will Legionnaires disease and record-breaking GI outbreaks cause the cruise lines to overhaul their sanitation processes and take responsibility for their passenger’s wellbeing? Or will the CDC cuts embolden the cruise lines to continue to shift the blame to passengers because of their “poor hygiene?”
Have a question or comment? Please leave one below or join the conversation on our Facebook page.