Hundreds sickened on cruise ships

At least 66 passengers and 17 crew members have come down with a gastrointestinal illness aboard the Crown Princess, seen here in July 2006. The illness may have been caused by the norovirus, the ship's operator said. Click through the gallery to see some other recent cruises affected by unfortunate events.

A federal judge has ruled Carnival liable and responsible for the engine fire that left the ill-fated Triumph cruise adrift in the Gulf of Mexico in February 2013. More than 4,200 passengers endured power outages, overflowing toilets and food shortages.

Princess Cruises' Caribbean Princess, seen here, cut its seven-day trip short after at least 165 passengers and 11 crew members reported being ill, the cruise company said January 31.

Nearly 700 crew and passengers fell ill aboard Royal Caribbean's Explorer of the Seas, which returned home to New Jersey on January 29. It is the highest number of sick people reported on any cruise ship in two decades, according to the Centers for Disease Control and Prevention.

In 2013, the Silver Shadow, run by Silversea Cruises, failed a CDC health inspection over concerns about hiding food in crew cabins.

On Memorial Day last year, a fire aboard Royal Caribbean's Grandeur of the Seas cut short a seven-day cruise to Port Canaveral, Florida, and the Bahamas. The ship changed its course and sailed under its own power to Freeport in the Bahamas.

Carnival Legend, shown here in 2012, had to cancel a scheduled March stop on Grand Cayman after propulsion system problems hampered its sailing speed. It arrived in Tampa, Florida, hours ahead of schedule.

The Carnival Dream, shown here at its North American debut in November 2009, lost power in March, and some of its toilets stopped working temporarily. For a time, no one was allowed to get off the vessel, docked at Philipsburg, St. Maarten, in the eastern Caribbean.

During a surprise visit in August 2012, CDC inspectors found multiple sanitation violations on the Holland America ship ms Veendam (shown here in March 2012). The CDC found enough violations, including brown liquid dripping on clean dishes and a fly on the buffet, to give the Veendam a failing grade.

A fire in the Carnival Splendor engine room in November 2010 crippled the cruise ship, stranding passengers off the coast of Mexico for several days without air conditioning or hot showers.

• The Royal Caribbean's Grandeur of the Seas was struck during back-to-back cruises ending Saturday


• That won't stop it from setting off Saturday for a third cruise


• Norovirus is a common cause of diarrhea and vomiting among cruise ship passengers


• It causes as many as 800 U.S. deaths per year, CDC says

(CNN) -- Ugh.

Three outbreaks of illness affecting more than 100 people each have been reported aboard two cruise liners -- two of them in back-to-back cruises of the same ship -- according to the nation's leading health protection agency.

The double dose of ill-fated cruises struck the Royal Caribbean's Grandeur of the Seas, the Centers for Disease Control and Prevention said Friday. During the ship's April 5 to April 12 cruise, 105 of the nearly 3,000 passengers and crew were affected -- primarily with vomiting and diarrhea, the disease agency said.

Sick cruise passengers stuck in rooms

'OutFront' remembers the 'Poop Cruise'

During the ship's cruise the prior week, 117 passengers and crew members were struck, according to the CDC.

Two CDC Vessel Sanitation Program environmental health officers and an epidemiologist were to board the vessel in Baltimore, Maryland, on Saturday to conduct an investigation. Specimens were being collected to be sent to the CDC lab for testing.

"We'll be working with both the medical teams as well as the crew on board the vessel and the cruise line with doing follow ups," Bernadette Burden, a CDC spokeswoman, told CNN affiliate WJZ. "Really taking a look at their cleaning, sanitation and hygiene practices that are being employed on the ship to interrupt the spread of disease."

But the ship's owners were planning to plunge onward, departing as scheduled at 4 p.m. Saturday on the next cruise -- seven nights to the Bahamas. Royal Caribbean told WJZ that any would-be passengers feeling a little queasy about the prospect of leaving Saturday aboard the twice-stricken ship could reschedule.

The third outbreak affected Princess Cruise's Crown Princess during a week-long cruise ending Saturday.

In all, 152 of the more-than 4,000 passengers and crew were sickened.

A lone CDC Vessel Sanitation Program environmental health officer was to board the ship upon its arrival Saturday in Los Angeles "to conduct a targeted environmental health assessment, and evaluate the outbreak and response activities," the CDC said.

The chief suspect behind all three waves of illness is norovirus, a highly infectious virus that can be picked up through contaminated food or water or by touching contaminated surfaces. It causes inflammation of the stomach, intestines or both, often leading to stomach pain, nausea, vomiting and diarrhea.

Each year in the United States, it causes 19 million to 21 million illnesses, and contributes to 56,000 to 71,000 hospitalizations and as many as 800 deaths, CDC says.

Cruise ships are a prime target.

"We have so many people together in a closed environment, eating in the same place," Catherine Troisi, associate professor of management, policy and community health at the University of Texas School of Public Health, told WJZ. "That's why you see it."

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