Of the over 200 active cruise ships the Centers for Disease Control and Prevention (CDC) has examined, only 20 earned a perfect 100-point score during their most recent inspection.

Royal Caribbean International and Princess Cruises each have three ships that currently have perfect scores, more than any other cruise line.

Celebrity Cruises, Norwegian Cruise Lines, Seabourn Cruise Line, and Disney Cruise Lines are tied for second with two ships with 100-point inspection scores.

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The vast majority of cruise ships get passing scores from the Centers for Disease Control and Prevention (CDC), which performs sanitation inspections on ships that operate in the US.

But a small handful of ships get a perfect score of 100 points during their inspections. Of the over 200 active cruise ships the CDC has examined, only 20 earned a 100 during their most recent inspection. Royal Caribbean International and Princess Cruises each have three ships that currently have perfect scores, more than any other cruise lines.

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For Royal Caribbean, those ships are Brilliance of the Seas, Navigator of the Seas, and Rhapsody of the Seas. They represent 12.5% of Royal Caribbean's ships that have been examined by the CDC, which have scored an average of 95.5 during their most recent inspections. No Royal Caribbean ships currently have failing scores.

Regal Princess, Sea Princess, and Star Princess are the Princess Cruises ships that have received perfect scores from the CDC during their most recent inspections. They represent 18.8% of Princess' active ships that have been examined by the CDC, which have scored an average of 96.3 during their most recent inspections. No Princess ships currently have failing scores.

Celebrity Cruises, Norwegian Cruise Lines, Seabourn Cruise Line, and Disney Cruise Lines are tied for second with two ships with 100-point inspection scores. Viking Ocean Cruises, P&O Cruises, Holland American Line, Aida Cruises, Costa Crociere SpA, and MSC Cruise Management (UK) Limited each have one.

Have you worked on a cruise ship? Do you have a story to share? Email this reporter at mmatousek@businessinsider.com.