In the last two weeks, two cruise liners have seen their elegant guests turned into diarrhea zombies trapped aboard floating tins of squalor. The worst of the incidents peaked on Sunday when Royal Caribbean's Explorer of the Seas limped into port with 564 of its 3,050 or so passengers having fallen ill.  The guests were suffering from symptoms that sound like norovirus, mainly perpetual diarrhea and vomiting. "I started with upset stomach and vomiting, and that lasted all night and into the morning," a passenger told CNN. 

The situation on the Explorer was so serious, that the Centers for Disease Control were consulted. And according to the CDC, around 18 percent of passengers and four percent of the crew members were sick. That outbreak was severe enough that Royal Caribbean decided to bring back the ship early and sanitize the boat.

"After consultation between our medical team and representatives of the U.S. Centers for Disease Control and Prevention, we think the right thing to do is to bring our guests home early, and use the extra time to sanitize the ship even more thoroughly," the cruise line said in a statement. 

The Explorer's woes come on the heels of another Royal Caribbean cruise being turned into a floating sick barge. On January 17th, the Majesty of the Seas came home early citing an "elevated number of persons with a gastrointestinal illness." The cruise line said that 66 of the ship's 2581 passengers (around two percent) were showing symptoms. "I spent like the whole night on the toilet," a passenger told WPLG-tv

This seems to be the time of the year when bad things tend to happen to these massive floating resorts. It was February of 2013 when CNN became the nation's leader in Poop Cruise coverage. The 24-hour cable network could not rip itself away from Carnival Cruises' Triumph, the cursed ship where toilets stopped working and its patrons were made to defecate in plastic bags, after the power and engines failed stranding it the Gulf of Mexico. And on a more tragic, this month also marked the two-year anniversary of the Costa Concordia crash. The ship ran aground off the coast of Italy in January 2012, partially capsizing and killing 32 people.