More than 70 people got sick in a gastrointestinal illness outbreak during a cruise on Royal Caribbean's Serenade of the Seas.
Among the 1,874 guests aboard the ship, 71 reported being ill during a cruise that will end on October 2, 2025, along with one crew member, according to the Centers for Disease Control and Prevention (CDC).
The outbreak was reported to the CDC on Sept. 28, 2025. 3.79% of passengers and 0.11% of crew members reported gastrointestinal issues. The predominant symptoms of the infected individuals were vomiting and diarrhea.
The CDC listed the causative agent as norovirus, a highly contagious virus that spreads easily through contaminated water, food, and surfaces.
Consequently, the cruise line implemented heightened cleaning and sanitation measures onboard, including:
- Increased cleaning and disinfection
- Collecting stool specimens from gastrointestinal illness cases for testing
- Isolating ill passengers and crew
- Consulting with the Vessel Sanitation Program (VSP) regarding sanitation procedures and illness reporting.
"The health and safety of our guests, crew, and the communities we visit are our top priority," Royal Caribbean Group told USA TODAY.
"To maintain an environment that supports the highest levels of health and safety onboard our ships, we implement rigorous cleaning procedures, many of which far exceed public health guidelines."
Serenade of the Seas is currently on a 13-night voyage one-way from San Diego, California, to Miami, Florida.
Cruise ship GI illness outbreaks now surpass reported cases in 2024
The norovirus outbreak on Serenade of the Seas is the 19th gastrointestinal illness outbreak on a cruise in 2025. Comparatively, 18 cases met the CDC's threshold for public notification in 2024.
The following cruise ships have reported outbreaks in 2025, along with the causative agent:
- Sea Cloud Cruises: Sea Cloud Spirit — January 4-10, 2025 (Ciguatera, presumed)
- Silversea Cruises: Silver Ray — January 4-20, 2025 (E. coli)
- Holland America Line: Volendam — January 4-25, 2025 (Norovirus)
- Viking Ocean Cruises: Viking Mars — January 10-24, 2025 (Norovirus)
- Princess Cruises: Coral Princess — January 20-February 5, 2025 (Norovirus)
- Royal Caribbean International: Radiance of the Seas — February 1-8, 2025 (Norovirus)
- Holland America Line: Rotterdam — February 2-14, 2025 (Norovirus)
- Holland America Line: Eurodam — February 19-March 1, 2025 (Norovirus)
- Princess Cruises: Coral Princess — February 21-March 9, 2025 (Norovirus)
- Holland America Line: Rotterdam — March 7-16, 2025 (Norovirus)
- Cunard Line: Queen Mary 2 — March 8-April 6, 2026 (Norovirus)
- Seabourn Cruise Line: Seabourn Encore — March 16-April 9, 2025 (Norovirus)
- Viking Expedition: Viking Polars — April 11-23, 2025 (Norovirus)
- Linblad Expeditions: National Geographic Sea Lion — April 15-29, 2025 (Unknown)
- Holland America Line: Zuiderdam — January 4-May 9, 2025 (Unknown)
- Holland America Line: Eurodam —April 12-May 5, 2025 (Unknown)
- Regent Seven Seas: Seven Seas Explorer — April 26-May 14, 2025 (Unknown)
- Royal Caribbean International: Navigator of the Seas — July 4-11, 2025 (Norovirus)
- Royal Caribbean International: Serenade of the Seas — September 19-October 2, 2025 (Norovirus)
Last year, most outbreaks were attributed to norovirus (15 out of 18). However, E. coli and Salmonella were also identified on cruise ships.
Although cruises often get a bad reputation for norovirus outbreaks, the CDC claims that ships are only responsible for about 1% of reported norovirus outbreaks. The highly contagious virus can also spread in confined spaces like camps, hotels, and college dorms.
Norovirus outbreaks are also on the rise across the United States
According to the CDC, norovirus cases increased throughout the 2024-2025 season, which lasted from August 1, 2024, to July 31, 2025.
During that time frame, 2,675 norovirus outbreaks were reported by NoroSTAT-participating states. There were 1,478 norovirus outbreaks reported by the same states throughout the previous seasonal period.
How to protect yourself from norovirus on a cruise ship
While onboard, you should follow all recommended health precautions, such as washing your hands before entering the buffet and after using the restroom.
It's also smart to limit your time in the crowded cruise ship buffet. Even if you thoroughly wash your hands before entering, it is hard to maintain strict hygiene standards with the high volume of guests coming and going.
Next, consider taking the stairs more often than the elevators. With hundreds (if not thousands) of passengers on a cruise ship, elevators typically feel cramped and hot. On the other hand, stairwells are quieter and reduce your time in extra-confined spaces.
