India, July 3 -- A norovirus outbreak aboard the Ruby Princess sickened more than 120 passengers and crew members during a 20-day round-trip voyage to Alaska and Canada, according to the US Centres for Disease Control and Prevention, marking the third such outbreak on a Princess Cruises ship so far this year.

The CDC said 102 of the ship's 3,032 passengers and 23 of its 1,144 crew members reported symptoms of acute gastrointestinal illness during the voyage, which departed San Francisco on June 12 and returned Thursday morning after stops in Alaska and British Columbia. The outbreak was formally reported to the agency's Vessel Sanitation Program on June 28, with laboratory testing of stool samples confirming norovirus as the cause.

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