CDC: Stomach bug strikes second cruise ship

Story highlights

More than 5% of passengers on the Caribbean Princess report being ill

A spokeswoman says the outbreak has been confirmed as norovirus

Passengers and crew experience vomiting and diarrhea

CNN  — 

Just when cruise lines thought they might be headed for calmer waters …

At least 162 passengers and 11 crew members have reported being ill on board Princess Cruises’ Caribbean Princess, according to the Centers for Disease Control and Prevention.

The institute said health officers would board the ship in Houston to investigate the gastrointestinal illness, which is causing vomiting and diarrhea.

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The news follows reports of sickness this week on another cruise ship, this one from the Royal Caribbean line.

Nearly 700 crew and passengers fell ill aboard the Royal Caribbean’s Explorer of the Seas, the highest number of sick people reported on any cruise ship in two decades, CDC data show.

MIAMI, UNITED STATES:  The Royal Caribbean Explorer of the Seas cruise ship heads south-east from Miami off the coast of South Florida 24 April 2005.  Miami-Dade county is recognized as the cruise ship capital of the world.  AFP PHOTO/Roberto SCHMIDT  (Photo credit should read ROBERTO SCHMIDT/AFP/Getty Images
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That ship returned home Wednesday, two days earlier than expected.

To compare the cruises, 5.22% of passengers on the Caribbean Princess reported being ill, versus 20.5% on the Explorer of the Seas.

The outbreak on board the Caribbean Princess has been confirmed as norovirus, according to Julie Benson, a spokeswoman for Princess Cruises.

Are cruise ships floating petri dishes?

Noroviruses spread easily and are a common cause of gastroenteritis, which produces vomiting and diarrhea.

Norovirus is also suspected on board the Explorer of the Seas, though the cause of the illness there has not been confirmed.

Caribbean Princess is expected in Houston early Friday. The seven-day cruise is being cut short by one day.

Sick passengers are being asked to stay in their cabins, while staff disinfect public areas such as restrooms and elevators.

The decision to cut the trip short was made based on forecasts for heavy fog, not the outbreak, Benson said.

CNN first learned of the stricken Princess ship from a Twitter post by the Houston Chronicle.

Royal Caribbean cruise ship returns home - with a sickness record

CNN’s Miriam Falco contributed to this report.