Norwegian Cruise Line is working with the Centers for Disease Control and Prevention after three passengers who sailed aboard Norwegian Prima in May and July 2026 were diagnosed with Legionnaires’ disease.

In a notice issued to guests and travel partners on September 1, NCL said it is not yet known whether the passengers were exposed through the ship’s water system or another source. The investigation remains ongoing.

The cruise line said it tested water-related equipment and fixtures aboard Norwegian Prima, including hot tubs, showers and faucets. According to the notice, all test results received so far have been negative, while additional testing will be conducted as part of the investigation.

NCL said it was sharing the health information as a precaution and emphasized that the health and safety of its passengers remain a priority. Most people diagnosed with the illness recover with appropriate medical care, which commonly includes