Another cruise ship horror story is making headlines this morning as a Royal Caribbean voyage was cut short by two days when more than 600 passengers got sick.

CAUGHT ON TAPE: Drunk Cruise Passenger Falls Overboard

Passengers and crew members reported vomiting and diarrhea. Royal Caribbean says the symptoms are consistent with a norovirus outbreak and passengers will be compensated for the shortened vacation.

The cruise ship left New Jersey Jan. 21 for the Caribbean.

Dr. Manny Alvarez of joined Martha MacCallum this morning to discuss the outbreak. He outlined why cruise ships are so vulnerable to these situations.

Alvarez explained that the virus is extremely contagious and can spread in no time to hundreds of people.

"You cannot get off [the ship]! Everybody's confined, it's highly contagious," he said.

Federal health officials have arrived on the scene to investigate.