The world's largest cruise ship was held in port Monday for intensive cleaning after a second outbreak of gastrointestinal illness in two voyages sickened 106 people.

More than 380 passengers and crew members aboard Royal Caribbean's Freedom of the Seas were sickened by norovirus during a Nov. 26-Dec. 3 Caribbean cruise. The ship was cleaned before its next cruise, but 97 passengers and 11 crew members became sick with the same illness last week, officials at the Miami-based cruise line said.

The U.S. Centers for Disease Control recommended keeping the ship in port and will oversee repeated cleaning of "high-touch" surfaces such as door handles, railings and elevator buttons, officials said. Two additional doctors and 45 more cleaning staff will be aboard for its next voyage, now scheduled to begin Tuesday.

The ship carried more than 3,900 passengers on its latest cruise.

Another ship, Princess Cruises' Sun Princess, also undergoing a thorough cleaning after docking at Port Everglades on Sunday with 97 sick passengers.

"This is not a very serious outbreak, but we did treat it as we treat all increased incidents — very immediately and swiftly," said Julie Benson, spokeswoman for Santa Clarita, Calif.-based Princess. The ship carried about 1,950 passengers.

Norovirus is a group of viruses that cause stomach flu symptoms such as diarrhea, vomiting and stomach cramps, according to the CDC. It spreads through contaminated food or liquids, contaminated surfaces or direct contact with someone who is infected. Last month, nearly 700 passengers fell ill on the Carnival Liberty during a cruise.