(2:15 p.m. EDT) -- When it comes to cruise ship sanitation, Royal Caribbean's 225,282-ton, 5,400-passenger Oasis of the Seas is a model of proper hygiene.

On June 26, the world's largest cruise ship scored a perfect 100 on its CDC vessel sanitation inspection, the stringent (and surprise) cruise ship cleanliness exam conducted twice a year by the Centers for Disease Control and Prevention. (It earned a 97 on its first-ever test, conducted on January 23.)

There were some minor infractions, but none were deemed serious enough to deduct points. For instance, according to the report, "the location of several bowls of food [in Oasis' Solarium Cafe] required excessive reaching. Passengers could potentially contaminate food on display with their arms, clothing or jewelry. This was corrected."

Meanwhile, another headline-grabbing ship -- the brand-new 155,873-ton, 4,100-passenger Norwegian Epic -- has yet to take its first sanitation pop quiz.

Looking across the industry over the past three months, a number of other ships have earned perfect scores, including Caribbean Princess, Diamond Princess, Carnival Freedom, Radiance of the Seas, Zuiderdam, Norwegian Pearl and Oosterdam. When it comes to onboard cleanliness in general, germophobes will be happy to know that there have been no failing scores -- anything under an 86 -- since a small private vessel, Albatross, earned a 69 in February.

The one mainstream ship that stands out over the past several months is Celebrity Summit. The ship received an 87 during its June 20 inspection, just barely eking out a passing grade. Summit was docked points for numerous violations, including a dairy creamer which was tested at 80 degrees Fahrenheit (should be maintained at 41 degrees or less); also, a children's toilet room did not have a waste receptacle with an airtight lid. A Celebrity Cruises spokesperson did not respond to a request for comment by press time.

Through its Vessel Sanitation Program, the CDC -- a United States agency that monitors a range of issues relating to public health -- inspects cruise ships with foreign itineraries that call on U.S. ports and that carry 13 or more passengers. Cruise ships are subject to inspections twice a year. The inspections are conducted to ensure that vessels are maintaining adequate levels of sanitation and to provide guidance to vessel staff when needed.

--by Dan Askin, Associate Editor

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