Overview

• Thirteen gastrointestinal illness outbreaks have been reported on cruise ships in 2025, with ten confirmed as norovirus, putting this year on track to surpass 2024's total of 18 outbreaks.
• Recent outbreaks on the Eurodam, Zuiderdam, and National Geographic Sea Lion sickened approximately 150 passengers and crew, with two cases still awaiting pathogen confirmation.
• The CDC attributes the surge to a newly dominant strain of norovirus, which is also driving higher land-based infection rates this year.
• Cruise ships' close quarters and shared facilities create ideal conditions for the rapid spread of the highly contagious virus, which resists many common disinfectants.
• Cruise lines, in coordination with the CDC, have adopted heightened cleaning protocols and isolation measures to curb transmission of the illness.