(Photo of the Coral Princess courtesy of Princess Cruises)

Princess Cruises’ Coral Princess arrived in Los Angeles today after reporting that 71 passengers and six crew members reported gastrointestinal symptoms during the April 12-27 voyage.

The Centers for Disease Control and Prevention said onboard tests confirmed the illness was caused by norovirus.

A CDC environmental health officer will board the ship to conduct an assessment and evaluate the outbreak and response. Princess confirmed there was an "elevated incidence of gastrointestinal illness" but said "by the end of the cruise, there were no new cases of ill passengers or crew members."

Still, in response to the outbreak, Princess increased cleaning and disinfection procedures, kept passengers and crew informed, and consulted with the CDC on sanitation plans, including a staged disembarkation for active cases to limit transmission.

Cruise ships are required to report the total number of gastrointestinal illness cases evaluated by the medical staff before the ship arrives at a U.S. port when sailing from a foreign port. A separate notification is required when the gastrointestinal illness count exceeds 2 percent of the total number of passengers or crew onboard, and the information is publicly posted when the number exceeds 3 percent.

The 71 passengers reporting vomiting and diarrhea on the Coral Princess comprise 3.63 percent of the 1,958 guests onboard. The six crew members are 0.68 percent of 881.

It is the fifth norovirus outbreak on a cruise ship this year. A sixth outbreak was reported on the Norwegian Pearl March 26-April 6 but has not been confirmed as norovirus.

The Coral Princess is moving to Alaska in May to operate seven-day “Voyage of the Glaciers” cruises between Vancouver and Anchorage (Whittier).

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