At least 27 people are sick on the Seven Seas Mariner with a gastrointestinal (GI) infection, according to the Centers for Disease Control and Prevention (CDC). The luxury ship reported the outbreak to the CDC on January 29, 2026.
This is the first cruise ship to report a GI outbreak to the CDC in 2026. Last year the CDC reported a total of 23 outbreaks, the most ever in a single year.
Cruise ships are required to report GI outbreaks to the CDC when they sail into American ports and at least 3% of the ship’s passengers or crew have GI symptoms. Currently, 21 of 631 (3.1%) passengers and 6 of 458 (1.3%) crew members are sick on the Seven Seas Mariner.
The CDC currently lists the outbreak’s causative agent as unknown. The ship’s crew collected stool specimens for testing according to the CDC.
The likely cause of the outbreak is norovirus. Norovirus is the most common cause of GI outbreaks on cruises, accounting for 17 of the 23 outbreaks last year. The tight living quarters and shared eating spaces make cruises the ideal environment for GI viruses like norovirus to spread.
The Seven Seas Mariner completed its 21-night voyage on February 1 in Hawaii. Regent Seven Seas Cruises, the cruise line that operates the ship, has not issued a public statement regarding the outbreak yet.