By Forrest Brown, CNN

(CNN) — A gastrointestinal illness has broken out this week on the Radiance of the Seas cruise ship, according to the US Centers for Disease Control and Prevention.

Some 89 of the 2,164 passengers onboard have been affected by the outbreak on the Royal Caribbean International ship, the CDC said. That’s around 4.1% of the passengers. Only two of the 910 crewmembers have reported symptoms.

The CDC did not specify what type of gastrointestinal illness this is. The predominant symptoms reported have been diarrhea and vomiting, the health agency said.

This particular voyage for Radiance of the Seas started February 1 and is scheduled to end on Saturday. The outbreak was reported to the CDC’s Vessel Sanitation Program on Tuesday. According to the website CruiseMapper, Radiance of the Seas departed Tampa, Florida, with several ports of call in the western Caribbean.

The CDC said that the sick passengers and crew have been isolated from the rest of the people on the ship. The ship has also “increased cleaning and disinfection procedures” and “collected stool specimens … for testing.”

In an emailed response to CNN Travel, a Royal Caribbean Group spokesperson said, “Enhanced measures have been implemented onboard in an abundance of caution to protect the health and comfort of all our guests and crew.”

Tracking illnesses

The Vessel Sanitation Program said in its report that “norovirus is often a cause of gastrointestinal illness outbreaks on cruise ships, but we don’t always know the cause of the outbreak when we begin an investigation. Finding the agent that caused an outbreak (causative agent) can take time.”

Norovirus cases started surging at the start of 2025, and 2024 was the worst year in over a decade for stomach bugs on cruise ships.

To help avoid the spread of illness, the CDC encourages frequent handwashing and getting plenty of rest and water. For more health tips, visit the CDC’s guidance page on healthy cruising.

The-CNN-Wire
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