These cruise ships got the best (and worst) CDC sanitation scores

Gastrointestinal illnesses like norovirus can be unfortunate anywhere, but they can be especially miserable on cruise ships, where they can easily spread without proper sanitation.

The Centers for Disease Control and Prevention’s Vessel Sanitation Program is specifically designed to help keep GI illnesses from spreading on cruises by inspecting vessels, responding to outbreaks, training ship supervisors, and more.

So far, this year, only two cruise ships have failed inspection, but several others have been close to the edge. Here’s how to find the sanitation reports for any ship sailing to the U.S.

How are ships scored?

Ships are scored on a scale of 100 for how well they’re keeping standards set in the VSP Operations Manual and given recommendations for addressing any issues.

A score of 86 or above is considered satisfactory. Anything below that is considered failing.

Three U.S. cruise lines' ships have been right at 86 this year:

• Carnival Cruise Line’s Carnival Breeze in March
• Princess Cruises’ Caribbean Princess in March
• Ritz-Carlton Yacht Collection’s Evrima in February

Additionally, MSC Cruises’ MSC Magnifica scored an 86 in May . MSC Cruises is headquartered in Switzerland and the third largest cruise company in the world, behind Carnival Cruise Line and Royal Caribbean International.

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Which ships have failed inspection?

Hapag-Lloyd Cruises ’ Hanseatic Inspiration scored a 62 in September . Among the violations, the CDC VSP report said, “Supervisors were inadequately monitoring critical and high-risk food processes, permitting unsafe practices to continue in food preparation areas” and several food items were stored at incorrect temperatures.

"Hapag-Lloyd Cruises has consistently met the strict hygiene requirements for many years with exemplary results that far exceed the required minimuum," Hapag-Lloyd Cruises senior communications manager Karen Schmidt said in a statement to USA TODAY. "We deeply regret that the HANSEATIC inspiration did not achieve the required score for the first time. The result of this inspection in no way reflects our high standards."

Schmidt said the German cruise line's immediately began investigating and rectifying operational deficiencies, and brought both inside and outside experts in to support new measures. The cruise line is also enhancing training for all employees and revising hygiene protocols across ships.

"We will use this opportunity to improve our processes in all areas and ensure that all our ships deliver the quality experience our guests expect," Schmidt added.

Only one U.S. cruise line vessel scored below 86 this year. Margaritaville at Sea Paradise scored an 83 in May , but then 92 more recently in July. Among the violations in May were several out of order appliances, no soap at a hand washing station, and too many people in the whirlpool.

How to find out a ship’s score

VPS inspection reports are publicly available and posted online in a searchable database on the CDC’s website .

Results can be narrowed by ship, cruise line, inspection date and score category.

Have any ships scored a 100?

Twenty ships have scored a perfect 100 this year:

• Carnival Cruise Line’s Carnival Spirit in September
• Celebrity Cruises’ Celebrity Ascent in January
• Celebrity Cruises’ Celebrity Equinox in February
• Disney Cruise Line’s Disney Fantasy in January
• Holland America Line’s Zuiderdam in August
• MSC Cruises’ Explore I in January
• MSC Cruises’ MSC Meraviglia in July
• MSC Cruises’ MSC Seashore in May
• Norwegian Cruise Line’s Norwegian Bliss in June
• Norwegian Cruise Line’s Norwegian Breakaway in February
• Norwegian Cruise Line’s Norwegian Escape in January
• Norwegian Cruise Line’s Norwegian Gem in January
• Norwegian Cruise Line’s Norwegian Jewel in July
• Norwegian Cruise Line’s Norwegian Sky in May
• Oceania Cruises' Regatta in July
• Royal Caribbean International’s Brilliance of the Seas in May
• Royal Caribbean International’s Radiance of the Seas in July
• Seabourn Cruise Line’s Seabourn Odyssey in August
• Viking Expeditions’ Viking Polaris in April
• Viking Ocean Cruises’ Viking Orion in August

It’s worth noting that perfect scores do not mean there is zero risk of illness. For instance, Royal Caribbean’s Radiance of the Seas scored 100 in July, but had a norovirus outbreak in April and a salmonella outbreak in September.

Which cruise ships have norovirus outbreaks?

There are currently no ships listed as having norovirus outbreaks, but at least seven ships have had norovirus outbreaks this year and several others had other outbreaks, according to the CDC VSP.

Norovirus

• Celebrity Cruises’ Celebrity Constellation, Jan. 3 - 12
• Celebrity Cruises’ Celebrity Summit, May 24 - 31
• Cunard Line's Queen Victoria, Jan. 22 - Feb. 6
• Holland America Line’s Koningsdam, Feb. 17 - March 24
• P&O Cruises' Arcadia, Sept. 3 - Oct. 3
• Princess Cruises' Sapphire Princess, April 5 - May 7
• Royal Caribbean International's Radiance of the Seas, April 8 - 22

Other illnesses

• Royal Caribbean International's Allure of the Seas, May 20 - 24 – unknown
• Royal Caribbean International's Radiance of the Seas, Sept. 20 - 27 – salmonella
• Silversea Cruises' Silver Nova, March 31 - April 16 – E. coli

How to avoid norovirus on a cruise ship

The CDC recommends washing hands often and if you see someone getting sick, leaving the area and reporting it to cruise staff.

Passengers who get sick are urged to call the ship’s medical staff as soon as possible, follow all their instructions, and get plenty of rest and water.

(This story has been updated with new information.)

This article originally appeared on USA TODAY: These cruise ships got the best (and worst) CDC sanitation scores