Royal Caribbean International announced in a press release that it will be bringing back its Explorer of the Seas cruise liner because the company is unable to deliver the kind of vacation the guests were expecting.  The ship was out for a 10-day cruise, but will be returning two days early on Jan. 29.  Officials made the decision after an outbreak of gastrointestinal illness spiked over the weekend.  After returning to port, the company will complete the third intensive sanitizing process and leave the ship in dock for at least 24 hours before the next set of passengers embark.

According to Time Magazine, over 600 people have fallen ill on the cruise.  At this time, doctors aboard the cruise have not confirmed what the illness is, but the symptoms of the outbreak are vomiting and diarrhea.  Those symptoms are consistent with the highly contagious norovirus, the most common cause of acute gastroenteritis in the U.S.  Royal Caribbean is coordinating with the Centers for Disease Control and Prevention (CDC) and test results confirming the type of illness are expected mid-week.

The Explorer of the Seas is carrying 3,050 passengers and 1,165 crew members, reports NBC News.  The cruise departed Tuesday from Cape Liberty, New Jersey, with plans for stops in San Juan, Puerto Rico, St. Thomas, and St. Maarten.  Cases of the disease were seen in the first couple of days on the cruise, with many of these individuals having recovered already.  However, many passengers that have not yet fallen ill are concerned as they have seen others around them get sick with some even being hospitalized.

Norovirus is the most common cause of acute gastroenteritis in the U.S., resulting in about 21 million illnesses, between 56,000 and 71,000 hospitalizations and as many as 800 deaths.  The virus lingers on surfaces and spreads very easily.  Thorough washing of hands with hot water and soap and meticulous environmental cleaning can help stop the spread.

It is not yet clear whether the outbreak on the Explorer of the Seas has been linked to a severe form of norovirus known as the GII 4 Sydney strain.  The GII 4 Sydney strain was the bug blamed for another cruise outbreak last year on the Queen Mary 2.  According to the CDC, this strain is currently the most common source of norovirus in the U.S.  Also, during a voyage from Dec. 22, 2012 to Jan. 3, 2013, 204 passengers and 16 crew members developed norovirus.