PORT EVERGLADES, Fla. >> A cruise ship has returned to South Florida after concluding a Caribbean voyage that saw more than a hundred people develop a gastrointestinal illness on board.

Royal Caribbean International reported Friday that 105 of 1,991 guests and three of 772 crew members experienced a possible short-lived norovirus illness during the 11-night trip. 

They have responded well to over-the-counter medication being administered onboard the ship.

The cruise line says in a statement that crew members scrubbed the ship to help prevent the spread of the illness and again when it returned to port.

The source of the illness wasn’t immediately reported.

The Centers for Disease Control says the contagious norovirus causes about 21 million illnesses in the U.S. each year and contributes to 800 deaths.