(CNN) - A 10 day cruise to the Caribbean came to an early end after nearly 650 passengers and crew members fall sick from a mystery illness.
Royal Caribbean's Explorer of the Seas ship Voyage has been cut short. The vessel to return home early to New Jersey Wednesday, now that one in five of its more than 3,000 passengers have fallen sick with a mystery illness. A wave of sickness with symptoms similar to the highly contagious norovirus.
"Under the best of circumstances, these kinds of outbreaks are bound to happen. Cruise ships are a concentration of passengers that are in a confined space where there is a lot of constant interaction and that close interaction promotes the transmission of this virus which is transmitted very readily from person to person," Dr. William Schaffner said.
To help prevent transmission, sick passengers have been asked to stay confined to their rooms, encouraged to call for complimentary room service to stay fed and hydrated.
Back in the dining room, one passenger tells said there are no more self-service buffets.
"We are no longer allowed to touch anything. They serve us everything. They hand us our plates. They hand us our silverware. They hand us our cups, our forks, our food. You're not allowed to touch a thing," passenger Arnee Dodd said.
Washing hands is critical. The virus can contaminate a surface for days, landing on hands, then traveling to the mouth and causing infection.
When the ship finally arrives home on Wednesday, Royal Caribbean said staff will, "make certain that any remaining traces of the illness are eliminated...and will additionally provide a window of more than 24 hours where there are no persons aboard the ship."
For their Caribbean cruise gone wrong, the company said passengers will get a 50 percent refund, and a 50 percent credit towards the their next cruise ship booking.
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