Cruise Ship Hit With Gastrointestinal Illness Outbreak

The Centers for Disease Control and Prevention (CDC) reported yesterday that a cruise ship was hit with a gastrointestinal illness outbreak.

Regent Seven Seas Mariner had an illness outbreak on its most recent voyage that affected 3.3% of guests and 1.3% of crew members.

Cruise lines are required to report to the CDC anytime 2% or more of guests get sick on a sailing. If the number crosses 3%, it officially becomes an outbreak with details posted to the CDC’s Vessel Sanitation Program’s website.

The CDC reported that 21 guests and 6 crew members had diarrhea and the causative agent is unknown at this time.

In response to the outbreak, the cruise line took the following actions onboard the ship:

• Increased cleaning and disinfection procedures according to their outbreak prevention and response plan
• Collected stool specimens from gastrointestinal illness cases for testing
• Isolated ill passengers and crew
• Consulted with VSP about sanitation cleaning procedures and reporting ill cases

The CDC remotely monitored the situation and reviewed the ship’s response and sanitation measures.

This is the first illness outbreak on a cruise ship this year. In 2025, there were 23 outbreaks reported to the CDC.

Regent Seven Seas Mariner is currently on a 154-night cruises around the world that started in Miami on January 10 and will return back home on June 13, 2026.