- The CDC has found that the private hot tubs in staterooms of cruise ships are the main source of outbreaks.
- Twelve different causes of Legionnaires’ disease were linked to hot tubs located on balconies.
- Private hot tubs were not cleaned to the same standards as those onboard, resulting in rapid bacterial growth.
The CDC warns that a private hot tub placed on your balcony can cause severe respiratory diseases.
In October 2024 the CDC published a study on outbreaks caused by Legionnaires’ Disease aboard cruise ships. This disease was contracted specifically through the hot tubs found in the passengers’ cabins. The CDC received 12 reports of Legionnaires disease between November 2022 to June 2024. These cases were clustered on two cruise ships. The CDC was notified of 12 cases between November 2022 and June 2024. These cases clustered around two cruise ships. The CDC began an investigation, and it became clear that hot tubs in private homes were at the heart of the outbreak.
In its report, the CDC states that “Epidemiological, environmental, laboratory, and other evidence suggest that hot tubs on private balconies were the likely cause of two outbreaks of Legionnaires Disease among cruise ship guests.” These devices were subject to less strict requirements for operation than public hot-tubs, and the operating protocol was insufficient to prevent Legionella.
Legionnaires disease is caused by Legionella bacteria. It is important to clean and disinfect hot tubs after each use. The heat of the tubs makes them a petri dish perfect for bacteria. CDC guidelines did not require that private hot tubs be cleaned as thoroughly as public hot spas before this report.
When hot tubs are not maintained properly, they can cause Legionella to grow and spread. 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 said in a statement shared with Travel + Leisure.
Cruise ship passengers should be aware of hot tub risks and ensure that the spas are cleaned and disinfected prior to use. In a statement, the CDC said that travelers could also test the hot water of their hot tubs using test strips.
Report any respiratory symptoms as soon as possible to the cruise ship’s authorities.
