The Aurora is due to sail again from Southampton on Thursday evening

Some 1,800 people disembarked from the Aurora at 0900 GMT on Thursday after a 17-day cruise during which 500 of them had fallen ill with a virulent stomach bug.

Michelle Seaborn, a recent star of Channel 4's Wife Swap, on the cruise with husband Barry, said they were to sue P&O Cruises for "taking them hostage".

Ms Seaborn, 35, from Heywood in Greater Manchester, said she came down with the bug on Monday after staff took her passport to stop her leaving the ship and flying home from Gibraltar.

Ms Seaborn said: "It was an absolute nightmare. We were held hostage.

'Bug ruined my holiday' Eyewitness: Ship misery

"We got a clean bill of health from the doctor, but they wouldn't let us off or give us our passports.

"A P&O executive said they would only give them to us after we set sail from Gibraltar.

"I am suing them for kidnap - they didn't need to keep us on the ship did they?

"They didn't want us coming off the ship talking to the media."

Fellow passenger Tricia Campbell, 55, from Hatfield near Doncaster, said she was also considering legal action.

"I suffered from dehydration because of the vomiting and diarrhoea, which led to me getting a kidney infection which I've been on antibiotics for. I had terrible pains.

"I went on the holiday by myself and I thought I would make friends, but I hardly met anyone because I had to stay in my cabin for much of the time.

"It was a ruined holiday. I need a holiday to get over it because I have been confined to my cabin for a week.

"I will be writing to P&O and then I will consider my options."

Andrew Williams, 43, from south Wales, said: "Not enough was done early enough to prevent the spread of the infection."

"I will be passing everything on to my solicitor when we get home.

"The whole holiday has been ruined. It is just like being on board a hospital ship."

But other passengers said the outbreak of the Norwalk, or Noro, virus had not spoiled their fun.

Mary Stewart, from Wigtown in Dumfries, said: "I've had a great time, it has been wonderful. None of us were affected by the virus.

"Everything is wonderful about that ship, it really is."

Derek Mather, from Wetherby in West Yorkshire, said: "Yes, I was sick, but in 72 hours you recover and just get on with it.

"I'm 75 years old - I can stay at home and wrap myself in cotton wool or I can go out and see the world - and I intend to see a lot more of the world before I pop my clogs."

'Every measure taken'

The luxury liner, which left Southampton on 20 October, set off for another cruise at 2000 GMT on Thursday.

David Dingle, P&O managing director, told BBC News: "Our sanitation processes are working very well and we're continuing them on the next cruise and the one after that.

"I'm as confident as I can be that we've taken every measure possible to ensure there will not be another occurrence."

P&O has declined to offer a standard compensation package to the passengers, who paid up to �5,000 for the trip, saying it would consider cases individually.