SAN FRANCISCO (AP/CBSLA.com) — Officials say more than 80 people are possibly ill with the highly contagious Norovirus while on-board a cruise ship sailing to ports in California.

Princess Cruises spokeswoman Karen Candy says 83 passengers on the Crown Princess reported being sick while the ship was in San Francisco on Monday.

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Candy said Tuesday that cruise officials believe the cause of the illness is the Norovirus. That family of viruses is spread person-to-person and causes flu-like symptoms including nausea, vomiting, diarrhea and stomach cramping.

Candy says the ship’s staff began intense disinfecting of surfaces, and all sick passengers are being encouraged to remain in their rooms.

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“All individuals who are ill (currently 66 passengers and 17 crew members), have been isolated in their cabins until they are not contagious,” Candy said in a company statement.

The Crown Princess is on a seven-day California cruise that began in Los Angeles on Saturday and ends in Santa Barbara.

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