The Voyager of the Seas has been forced to abandon its planned trip through the Pacific Islands after three staff members were diagnosed with influenza and the cruise ship was denied entry to Vanuatu.

The ship, which can carry up to 4000 passengers, left Sydney on Tuesday for an 11-day cruise through the South Pacific.

Voyager of the Seas, which can carry up to 4000 passengers, left Sydney on Tuesday for an 11-day cruise through the South Pacific.

But when three members of staff tested positive for influenza, authorities in Vanuatu decided to refuse entry to the ship which will now modify its course.

"Voyager of the Seas will modify its itinerary following a decision by Vanuatu health authorities to deny port entry over concerns that three crew members have tested positive for influenza A," a spokeswoman for the company said on Saturday morning.