(Reuters) - A cruise ship will return to Florida a day early after 277 guests and crew suffered from gastrointestinal illness since departing on Sunday, Royal Caribbean Cruises said on Thursday.

All guests aboard the Oasis of the Seas, which will return to Port Canaveral on Saturday, will receive full refunds, Royal Caribbean Cruises spokesman Owen Torres said in an emailed statement.

“We think the right thing to do is to get everyone home early rather than have guests worry about their health,” Torres said. “Our guests sail with us to have great vacations, and we are sorry this cruise fell short.”

The number of those sickened was fewer than 4 percent of those on board, Torres said.

News media said the ship was hit by an outbreak of norovirus after arriving in Jamaica earlier this week. Torres said lab tests were pending to determine what the illness was.

The ship aborted a trip to Cozumel, Mexico, to return immediately to Port Canaveral, passenger Alan Thomas wrote on Twitter. “Tough situation, everyone maintaining a good attitude,” Thomas said.

Returning early allows the cruise line more time to clean and sanitize the ship before its next trip, Torres said.