Peter and Anita Wormald, of Hove Edge, have described the food poisoning outbreak, which left them with severe diarrhoea, fever and headaches, as the "worst present ever".

The couple started feeling unwell two days before the end of their fortnight break aboard the Independence of the Seas in June. Mr Wormald, 57, became so ill that he lost more than 10lb in weight and it took him six weeks to recover. The £2,500 break was a 50th birthday present for Mrs Wormald, a hairdresser.

Travel law experts Irwin Mitchell are representing the couple in legal action against tour operator Ideal Cruising.

Lawyer Rajbir Somel said: "Mr and Mrs Wormald had a truly awful experience and this is not the first time we have received complaints of illness on this cruise liner."

During the luxury cruise, the couple sent a series of meals back to the restaurant kitchen after they were served cold. They also came across curdled milk and yoghurts in faulty chiller cabinets.

Mr Wormald, a dental technician in Halifax, said: "The food wasn't up to the standard we were expecting and it spoiled what we hoped would be the perfect birthday celebration for Anita.

"On the last night we couldn't say any final farewells to people we'd met because we were so unwell we couldn't even leave our cabin. And it would appear we weren't the only ones – a number of people we met also suffered from similar illness.

"When we got home we went to our doctor and I had to spend a week off work as it still wasn't clearing up.

"We had to cancel a birthday party we were organising for Anita with 40 friends because we were still feeling so bad."

Tests showed the couple had both contracted campylobacter food poisoning and they were placed on a course of antibiotics.

Mrs Wormald said: "Peter has now recovered but it had a dreadful impact. Peter lost three-quarters of a stone and couldn't walk the dog for a month because he was so weak.

"It took him six weeks to return to normal and I still have not recovered. We've been on four cruises now but we seriously doubt we'll do one again because of what happened with this one."

Mr Somel said: "This is a very serious example of food poisoning and it turned what should have been a wonderful, celebratory holiday for Mr and Mrs Wormald into disaster."

Ideal Cruising said the company were agents and the responsibility lay with the cruise liners, in this case Royal Caribbean Internation-al. Nobody at Royal Caribbean International was available for comment.